Minorities Face Delays to Pancreatic Cancer Treatment Regardless of Diagnosis Setting

INTRODUCTION

Our analysis was designed to characterize the demographics and disparities between the diagnosis of pancreas cancer during emergency presentation (EP) and the outpatient setting (OP) and to see the impact of our institutions pancreatic multidisciplinary clinic (PMDC) on these disparities.

METHODS

Institutional review board-approved retrospective review of our institutional cancer registry and PMDC databases identified patients diagnosed/treated for pancreatic ductal adenocarcinoma between 2014 and 2022. Chi-square tests were used for categorical variables, and one-way ANOVA with a Bonferroni correction was used for continuous variables. Statistical significance was set at p < 0.05.

RESULTS

A total of 286 patients met inclusion criteria. Eighty-nine patients (31.1%) were underrepresented minorities (URM). Fifty-seven (64.0%) URMs presented during an EP versus 100 (50.8%) non-URMs (p = 0.037). Forty-one (46.1%) URMs were reviewed at PMDC versus 71 (36.0%) non-URMs (p = 0.10). No differences in clinical and pathologic stage between the cohorts (p = 0.28) were present. URMs took 22 days longer on average to receive treatment (66.5 days vs. 44.8 days, p = 0.003) in the EP cohort and 18 days longer in OP cohort (58.0 days vs. 40.5 days, p < 0.001) compared with non-URMs. Pancreatic Multidisciplinary Clinic enrollment in EP cohort eliminated the difference in time to treatment between cohorts (48.3 days vs. 37.0 days; p = 0.151).

RESULTS

Underrepresented minorities were more likely to be diagnosed via EP and showed delayed times to treatment compared with non-URM counterparts. Our PMDC alleviated some of these observed disparities. Future studies are required to elucidate the specific factors that resulted in these findings and to identify solutions.

Radiation Therapy Quality Assurance Analysis of Alliance A021501: Preoperative mFOLFIRINOX or mFOLFIRINOX Plus Hypofractionated Radiation Therapy for Borderline Resectable Adenocarcinoma of the Pancreas

PURPOSE

Alliance A021501 is the first randomized trial to evaluate stereotactic body radiation therapy (SBRT) for borderline resectable pancreatic ductal adenocarcinoma (PDAC) after neoadjuvant chemotherapy. In this post hoc study, we reviewed the quality of radiation therapy (RT) delivered.

METHODS AND MATERIALS

SBRT (6.6 Gy × 5) was intended but hypofractionated RT (5 Gy × 5) was permitted if SBRT specifications could not be met. Institutional credentialing through the National Cancer Institute-funded Imaging and Radiation Oncology Core (IROC) was required. Rigorous RT quality assurance (RT QA) was mandated, including pretreatment review by a radiation oncologist. Revisions were required for unacceptable deviations. Additionally, we performed a post hoc RT QA analysis in which contours and plans were reviewed by 3 radiation oncologists and assigned a score (1, 2, or 3) based on adequacy. A score of 1 indicated no deviation, 2 indicated minor deviation, and 3 indicated a major deviation that could be clinically significant. Clinical outcomes were compared by treatment modality and by case score.

RESULTS

Forty patients were registered to receive RT (1 planned but not treated) at 27 centers (18 academic and 9 community). Twenty-three centers were appropriately credentialed for moving lung/liver targets and 4 for static head and neck only. Thirty-two of 39 patients (82.1%) were treated with SBRT and 7 (17.9%) with hypofractionated RT. Five cases (13%) required revision before treatment. On post hoc review, 23 patients (59.0%) were noted to have suboptimal contours or plan coverage, 12 (30.8%) were scored a 2, and 11 (28.2%) were scored a 3. There were no apparent differences in failure patterns or surgical outcomes based on treatment technique or post hoc case score. Details related to on-treatment imaging were not recorded.

CONCLUSIONS

Despite rigorous QA, we encountered variability in simulation, contouring, plan coverage, and dose on trial. Although clinical outcomes did not appear to have been affected, findings from this analysis serve to inform subsequent PDAC SBRT trial designs and QA requirements.

Stereotactic body radiotherapy plus rucosopasem in locally advanced or borderline resectable pancreatic cancer: GRECO-2 phase II study design

Ablative doses of stereotactic body radiotherapy (SBRT) may improve pancreatic cancer outcomes but may carry greater potential for gastrointestinal toxicity. Rucosopasem, an investigational selective dismutase mimetic that converts superoxide to hydrogen peroxide, can potentially increase tumor control of SBRT without compromising safety. GRECO-2 is a phase II, multicenter, randomized, double-blind, placebo-controlled trial of rucosopasem in combination with SBRT in locally advanced or borderline resectable pancreatic cancer. Patients will be randomized to rucosopasem 100 mg or placebo via intravenous infusion over 15 min, before each SBRT fraction (5 × 10 Gy). The primary end point is overall survival. Secondary end points include progression-free survival, locoregional control, time to metastasis, surgical resection rate, best overall response, in-field local response and acute and long-term toxicity.

Neoadjuvant radioimmunotherapy in pancreatic cancer enhances effector T cell infiltration and shortens their distances to tumor cells

Radiotherapy is hypothesized to have an immune-modulating effect on the tumor microenvironment (TME) of pancreatic ductal adenocarcinoma (PDAC) to sensitize it to anti-PD-1 antibody (a-PD-1) treatment. We collected paired pre- and posttreatment specimens from a clinical trial evaluating combination treatment with GVAX vaccine, a-PD-1, and stereotactic body radiation (SBRT) following chemotherapy for locally advanced PDACs (LAPC). With resected PDACs following different neoadjuvant therapies as comparisons, effector cells in PDACs were found to skew toward a more exhausted status in LAPCs following chemotherapy. The combination of GVAX/a-PD-1/SBRT drives TME to favor antitumor immune response including increased densities of GZMB+CD8+ T cells, TH1, and TH17, which are associated with longer survival, however increases immunosuppressive M2-like tumor-associated macrophages (TAMs). Adding SBRT to GVAX/a-PD-1 shortens the distances from PD-1+CD8+ T cells to tumor cells and to PD-L1+ myeloid cells, which portends prolonged survival. These findings have guided the design of next radioimmunotherapy studies by targeting M2-like TAM in PDACs.

Stereotactic body radiotherapy with or without selective dismutase mimetic in pancreatic adenocarcinoma: an adaptive, randomised, double-blind, placebo-controlled, phase 1b/2 trial

BACKGROUND

Stereotactic body radiotherapy (SBRT) has the potential to ablate localised pancreatic ductal adenocarcinoma. Selective dismutase mimetics sensitise tumours while reducing normal tissue toxicity. This trial was designed to establish the efficacy and toxicity afforded by the selective dismutase mimetic avasopasem manganese when combined with ablative SBRT for localised pancreatic ductal adenocarcinoma.

METHODS

In this adaptive, randomised, double-blind, placebo-controlled, phase 1b/2 trial, patients aged 18 years or older with borderline resectable or locally advanced pancreatic cancer who had received at least 3 months of chemotherapy and had an Eastern Cooperative Oncology Group performance status of 0-2 were enrolled at six academic sites in the USA. Eligible patients were randomly assigned (1:1), with block randomisation (block sizes of 6-12) with a maximum of 24 patients per group, to receive daily avasopasem (90 mg) or placebo intravenously directly before (ie, within 180 min) SBRT (50, 55, or 60 Gy in five fractions, adaptively assigned in real time by Bayesian estimates of 90-day safety and efficacy). Patients and physicians were masked to treatment group allocation, but not to SBRT dose. The primary objective was to find the optimal dose of SBRT with avasopasem or placebo as determined by the late onset EffTox method. All analyses were done on an intention-to-treat basis. This study is registered with ClinicalTrials.gov, NCT03340974, and is complete.

FINDINGS

Between Jan 25, 2018, and April 29, 2020, 47 patients were screened, of whom 42 were enrolled (median age was 71 years [IQR 63-75], 23 [55%] were male, 19 [45%] were female, 37 [88%] were White, three [7%] were Black, and one [2%] each were unknown or other races) and randomly assigned to avasopasem (n=24) or placebo (n=18); the placebo group was terminated early after failing to meet prespecified efficacy parameters. At data cutoff (June 28, 2021), the avasopasem group satisfied boundaries for both efficacy and toxicity. Late onset EffTox efficacy response was observed in 16 (89%) of 18 patients at 50 Gy and six (100%) of six patients at 55 Gy in the avasopasem group, and was observed in three (50%) of six patients at 50 Gy and nine (75%) of 12 patients at 55 Gy in the placebo group, and the Bayesian model recommended 50 Gy or 55 Gy in five fractions with avasopasem for further study. Serious adverse events of any cause were reported in three (17%) of 18 patients in the placebo group and six (25%) of 24 in the avasopasem group. In the placebo group, grade 3 adverse events within 90 days of SBRT were abdominal pain, acute cholangitis, pyrexia, increased blood lactic acid, and increased lipase (one [6%] each); no grade 4 events occurred. In the avasopasem group, grade 3-4 adverse events within 90 days of SBRT were acute kidney injury, increased blood alkaline phosphatase, haematoma, colitis, gastric obstruction, lung infection, abdominal abscess, post-surgical atrial fibrillation, and pneumonia leading to respiratory failure (one [4%] each).There were no treatment-related deaths but one late death in the avasopasem group due to sepsis in the setting of duodenal obstruction after off-study treatment was reported as potentially related to SBRT.

INTERPRETATION

SBRT that uses 50 or 55 Gy in five fractions can be considered for patients with localised pancreatic ductal adenocarcinoma. The addition of avasopasem might further enhance disease outcomes. A larger phase 2 trial (GRECO-2, NCT04698915) is underway to validate these results.

FUNDING

Galera Therapeutics.

Endoscopic Ultrasound-Guided Fiducial Placement for Stereotactic Body Radiation Therapy in Patients with Pancreatic Cancer

Accurate delivery of stereotactic body radiotherapy (SBRT) to pancreatic tumors relies on successful EUS-guided placement of fiducial markers. The aim of this study is to report the technical feasibility and safety of EUS-guided fiducial placement and to evaluate the characteristics and technical benefit of SBRT in a cohort of patients with pancreatic cancer (PC). A retrospective chart review was performed for all (n = 82) PC patients referred for EUS-guided fiducial placement by a single endosonographer at a tertiary cancer center. Data regarding EUS-related technical details, SBRT characteristics, adverse events, and continuous visibility of fiducials were recorded and analyzed. Most patients included in the study had either locally advanced disease (32 patients, 39%) or borderline resectable disease (29 patients, 35%). Eighty-two PC patients underwent the placement of 230 fiducial markers under EUS guidance. The technical success rate of the fiducial placement was 98%. No immediate EUS-related adverse events were reported. The average time to the simulation CT after fiducial placement was 3.1 days. Of the 216 fiducial markers used for the SBRT delivery, 202 fiducial markers were visible on both the simulation CT and the cone beam CT scan. A median dose of 40cGY was given to all the patients in five fractions. Of these, 41% of the patients reported no SBRT-related toxicities during the follow-up. Fatigue and nausea were the most reported SBRT-related toxicities, which were seen in 35% of the patients post-SBRT. Our results demonstrate that EUS-guided fiducial placement is safe and effective in target volume delineation, facilitating SBRT delivery in PC patients. Further clinical trials are needed to determine the SBRT-related survival benefits in patients with pancreatic cancer.

Pathway Mutations are Associated with Clinical Outcomes in Localized Pancreatic Cancer Treated with Neoadjuvant Chemoradiation Followed by Surgery

PURPOSE/OBJECTIVE(S)

The purpose of this study was to determine if mutations in biological pathways are associated with clinical outcomes in patients with localized pancreatic cancer who undergo neoadjuvant chemoradiation followed by surgical resection.

MATERIALS/METHODS

Patients treated with neoadjuvant chemoradiation followed by oncologic resection from 2015-2019 who also underwent next generation sequencing (NGS) of the primary tumor were included in this retrospective analysis. NGS was done using either Foundation One (n = 20), in-house Solid Tumor Panel (n = 121), or Tempus XT (n = 1). Genes were included in pathway analysis if at least one patient harbored a mutation in the gene. Pathways were defined from the Molecular Signatures Database Hallmark, KEGG, and Reactome gene sets. A pathway was deemed mutated if at least one gene within the pathway was mutated. Univariable Cox regression was performed to determine the association between pathway mutation status and overall survival (OS) as well as progression-free survival (PFS).

RESULTS

In total, 142 patients met criteria for study inclusion. For pathway analysis, 329 genes met inclusion criteria. Patients were typically treated with neoadjuvant chemotherapy (either 5-fluorouracil-based or gemcitabine-based) followed by radiation. Patients received SBRT (n = 104, most commonly 33 Gy in 5 fractions) or conventionally fractionated radiation (n = 38, most commonly 50.4 Gy in 28 fractions). For clinical variables, worse OS was significantly associated with T stage (p = 0.036), N stage (p = 0.044), and lymphovascular invasion (LVI, p = 0.011); worse PFS was significantly associated with T stage (p = 0.0008), N stage (p = 0.022), LVI (p = 0.026), and conventional RT (p = 0.007). Mutations in major pathways were associated with worse OS, notably hedgehog signaling (p = 0.001), chromatin modifying enzymes (p = 0.002), WNT/beta-catenin signaling (p = 0.005), mismatch repair (0.006), E2F targets (p = 0.008), FLT signaling (p = 0.012), VEGF signaling (0.025), innate immune system (p = 0.026), and NOTCH signaling (p = 0.029). Pathway mutations associated with worse PFS included mismatch repair (p = 0.007) and hedgehog signaling (p = 0.013).

CONCLUSION

For pancreatic cancer patients that undergo neoadjuvant chemoradiation followed by oncologic resection of the primary tumor, mutations in key biological pathways are associated with OS and PFS. Characterizing the importance of common pathway mutations may become increasingly valuable to help categorize less commonly mutated genes assayed by NGS.

Characterization of DNA Damage Response-Associated Somatic Mutations in Borderline Resectable and Locally Advanced Pancreatic Cancer

PURPOSE/OBJECTIVE(S)

The role of radiation for pancreatic cancer remains controversial, with recent studies showing conflicting results, highlighting the need to develop biomarkers of radiation response. Despite its potential utility in predicting radiosensitivity, the landscape of somatic mutations in borderline resectable pancreatic cancer (BRPC) and locally advanced pancreatic cancer (LAPC), as related to DNA damage response (DDR), has not been well characterized. This study aimed to characterize the frequency of such mutations in a cohort of patients with BRPC/LAPC treated with neoadjuvant chemotherapy and stereotactic body radiotherapy (SBRT).

MATERIALS/METHODS

Mutational data was collected from patients with BRPC/LAPC treated at a single institution with neoadjuvant chemotherapy and SBRT, followed by surgical resection from 2016-2021. Chemotherapy consisted of modified FOLFIRINOX or gemcitabine/nab-paclitaxel, and patients were treated with SBRT in 33 Gy in 5 fractions. Genomic data was obtained from either endoscopic biopsy or surgical specimens, and next-generation sequencing was performed either in-house with a Solid Tumor Panel or with FoundationOne CDx. Specific emphasis was placed on the characterization of double-strand DNA break (DSB) repair genes, as this is the type of tumor cell damage traditionally induced by radiation therapy. Genes associated with the two main pathways of DSB repair, non-homologous end joining (NHEJ) and homologous repair (HR), were analyzed. Specific HR pathway mutations assessed were BLM, BRCA1/2, MRE11, NBN, PALB2, RAD50, RAD51B-D, and RAD54L, while PRKDC mutations were assessed for the NHEJ pathway. Mutations in ATM, an important initiator of DDR pathways, were also analyzed. Additionally, the frequency of mutations in TP53, CDKN2A and SMAD4 in patients with concomitant KRAS mutations was assessed.

RESULTS

Eighty-five patients were included in the study. Five (5.9%) patients had mutations in the NHEJ pathway of the PRKDC gene. Twenty (23.5%) patients had mutations in the HR pathway, including BRCA2 (10/85; 11.8%), PALB2 (5/85; 5.9%), BRCA1 (3/85; 3.5%), and RAD50 (1/85; 1.2%). Six (7.1%) patients had mutations in ATM. No patients were found to have mutations in BLM, RAD51B-D, RAD54L, or NBN. Amongst patients with KRAS mutations (72/85), concomitant mutations were observed in TP53 (47/85; 55.3%), CDKN2A (16/85; 18.8%), and SMAD4 (9/85; 10.6%).

CONCLUSION

Herein, we characterized the frequency of somatic mutations associated with DSB repair genes in patients with BRPC/LAPC. Data analysis on outcomes related to radiation response in patients with mutations in DDR pathways is ongoing, but will likely also benefit from multi-institutional efforts to increase the power to answer this question.

Utilization of the Triangle Volume in Patients with Localized PDAC Undergoing Pre-Operative SBRT: Report of Early Outcomes

PURPOSE/OBJECTIVE(S)

In patients with borderline resectable or locally advanced pancreatic adenocarcinoma (BRPC/LAPC), advances in neoadjuvant therapy have led to an increased proportion of patients undergoing margin negative resection. Nevertheless, locoregional recurrence rates remain high. We have previously reported that the location of locoregional recurrences in this setting map to the "Triangle Volume (TV)," the anatomical space between the celiac artery, superior mesenteric artery, common hepatic artery, and portal vein, which is enriched in extrapancreatic perineural tracts at risk for microscopic residual disease after resection. At the beginning of 2021, we systematically changed our target volume to include the TV, in addition to gross disease and involved vasculature. Herein, we report early locoregional failure outcomes after resection in the setting of BRPC or LAPC treated with pre-operative stereotactic body radiation therapy (SBRT) to the TV, as compared to historical rates.

MATERIALS/METHODS

Patients who received a diagnosis of BRPC or LAPC and who were treated at our institution with neoadjuvant chemotherapy (CTX) and SBRT between 2016 and 2022 were retrospectively reviewed. Between 2016 and 2020, the SBRT clinical tumor volume (CTV) included gross disease and full circumference of involved vasculature at the level of involvement. From 2021 onward, the CTV also included the TV. Survival was estimated using the Kaplan-Meier method. Statistical analyses were performed using scientific 2-D graphing and statistics software.

RESULTS

From January 2016 to December 2022, 204 patients with localized PDAC underwent neoadjuvant CTX followed by SBRT. After completion of SBRT, all patients proceeded with surgical exploration. Of these patients, 111 (54%) had LAPC and 92 (45%) had BRPC disease. All patients were treated with induction CTX, mostly commonly with FOLFIRINOX (N = 166, 81%). Following CTX, the most frequently used SBRT regimen was 33 Gy in 5 fractions (N = 191, 94%). 155 (67%) patients were treated between 2016 and 2020 to the traditional CTV, while 49 (24%) patients were treated after 2020 to a CTV that included the TV. The 2-year local progression free survival rate of patients treated with SBRT using the TV was 77.6% as compared to 47.5% in patients treated with the traditional CTV. Over a median follow up of 15.7 months (range: 1 to 78.2 months), 47% (N = 73 out of 155) of patients who underwent SBRT with the traditional CTV developed locoregional recurrence, but only 12% (N = 6 out of 49) treated with SBRT to the TV have thus far developed locoregional recurrence (p<0.0001).

CONCLUSION

In patients with localized PDAC who undergo pre-operative SBRT for BRPC/LAPC, targeting the TV may help reduce locoregional recurrence. More data and longer follow-up are needed to verify these findings and inform whether the TV may serve as a new standard for target volume delineation in this setting.

Local Time-to-Event Endpoint Under-Reporting and Variability in Pancreatic Cancer Trials Involving Radiotherapy

PURPOSE/OBJECTIVE(S)

The role of radiotherapy (RT) for pancreatic adenocarcinoma (PDAC) remains controversial, with recent studies showing conflicting results. Importantly, endpoints used to evaluate efficacy in recent RT trials for PDAC have been highly variable. As variability in time-to-event (TTE) endpoint definitions is demonstrated to influence outcomes in other cancers, it is critical that radiation oncologists develop consensus around optimal endpoint definitions to use in future PDAC trial design. Thus, we conducted a systematic review of PDAC trials involving RT to characterize the frequency and variability in local TTE endpoint reporting.

MATERIALS/METHODS

An electronic database search was conducted of PubMed, EMBASE, and Cochrane Library to identify phase 2 and 3 clinical trials published from 2010-2022 of localized PDAC involving RT that reported any TTE endpoint (e.g., local control). After excluding duplicates, two independent reviewers screened full-text manuscripts for inclusion. Trial characteristics and local TTE endpoints/definitions were tabulated.

RESULTS

Three hundred twenty references were screened and 79 trials were included, of which 73 (92%) were phase 2 and 26 (33%) were randomized. Twenty (25%) trials reported a local TTE endpoint; these were local control (LC; N = 6), local progression-free survival (LPFS; N = 4), freedom from local progression (N = 6), locoregional progression-free interval (N = 1), cumulative incidence of local recurrence (N = 1), time to failure of sustained LC (N = 1), and local disease-free survival (N = 1). LC (N = 6) had 5 unique definitions and was undefined once; 1 definition included death as an event. LPFS (N = 4) had 3 definitions; 2 did not consider death an event. Among trials with local TTE endpoints, 9 trials specified the definition of a local recurrence/progression. Four trials defined local recurrence based on RT volumes; one counted clinical evidence of recurrence (e.g., tumor bleed); and one counted a rise in tumor markers without evidence of distant metastases. The index time ("time-zero") was defined for local TTE endpoints in 10 trials, including start of RT (N = 4) or chemo (N = 1), end of RT (N = 1), diagnosis (N = 1), enrollment (N = 1), and time of surgery (N = 1).

CONCLUSION

Few pancreatic cancer trials involving RT report local TTE endpoints, with significant heterogeneity in endpoints used and their definitions. Development of consensus endpoint definitions will be critical for future PDAC trial design.

Visceral Artery Pseudoaneurysm Rates after Pancreatoduodenectomy in Patients Who Received Pre-Operative Radiation for Pancreatic Cancer

PURPOSE/OBJECTIVE(S)

The role of pre-operative radiation therapy (RT) for localized pancreatic ductal adenocarcinoma (PDAC) with peri-pancreatic vascular involvement remains controversial, with two recent randomized controlled trials, namely PREOPANC-1 and Alliance A021501, showing conflicting results. Opponents of pre-operative radiation point towards the unclear oncologic benefit and potential added toxicity. While hemorrhage from a pseudoaneurysm (PsA) rupture is a known rare but potentially fatal complication after pancreaticoduodenectomy (PD), with published incidence rates of around 2 to 5%, it has been increasingly common in the pancreatic cancer surgical community for pre-operative RT to be cited as a risk factor for PsA development, despite the absence of data supporting this notion. Certainly, accurate characterization of relevant RT-related toxicities is critical to prevent inaccurate decision-making regarding foregoing its use. As such, we aim to report on the incidence of PsA in a cohort of patients with PDAC who underwent pre-operative RT prior to PD at a high-volume center.

MATERIALS/METHODS

Consecutive patients treated with pre-operative RT via stereotactic body radiation therapy (SBRT) or intensity modulated radiation therapy (IMRT) prior to PD for borderline resectable or locally advanced PDAC were retrospectively reviewed. Incidence of radiographic or clinically apparent PsA was reported. We also characterized the timing of PsA identification in relation to surgery and RT, the artery in which the PsA developed, and the clinical outcomes of patients after PsA identification.

RESULTS

One hundred seventy-five patients met eligibility criteria for our analysis. Most of our cohort (163 patients, 93%) received SBRT to a median dose of 6.6 Gy x 5 (median BED10 54.78 Gy, range: 48 Gy - 61.92 Gy), and only 12 patients (7%) received IMRT in various fractionation and dose patterns (median BED10 62.94 Gy, range 59.47 Gy - 97.5 Gy). The median time between surgery and last contrast-enhanced abdominal imaging was 17 months (range: 0.23 - 68 months). There were fourteen visceral arteries among thirteen patients (7%) that were found to have a PsA on routine follow-up imaging or after a post-PD hemorrhage. The median time between completion of radiation and surgery to PsA were 19.5 weeks (range: 8.6 to 98.1 weeks) and 13 weeks (range: 1.6 to 87.9 weeks), respectively. The two most commonly involved arteries were the gastroduodenal and superior mesenteric arteries. Rate of PsA development was similar among patients treated with SBRT (7%) and IMRT (8%). In terms of Clavien-Dindo classification of complications, there were six patients with grade 3a complications, five patients with grade 4b complications, and two patients with grade 5 complications.

CONCLUSION

Compared to historical data, pre-operative RT does not appear to significantly increase the risk of PsA development after PD. More data on the impact of pre-operative radiation dose-fraction regimen and longer follow-up are needed.

The Prevalence and Management of Synchronous Prostate and Rectal Cancer

PURPOSE/OBJECTIVE(S)

Synchronous prostate and rectal cancer is rare and guidelines for co-management are not well established. This case series explores the prevalence of synchronous diagnosis and different treatment paradigms to propose a standardized approach to management.

MATERIALS/METHODS

We retrospectively reviewed all radiation treatments between 1/2017 and 12/2022 for curative intent treatment to both prostate and rectal cancer. Synchronous was defined as rectal or prostate cancer diagnosed within a 6-month period of each other. We collected baseline characteristics and treatment paradigms including the sequencing of chemoradiation (CRT), chemotherapy (CT), prostate boost, and surgery.

RESULTS

There were 10 out of 2204 total treated patients with prostate or rectal primary noted to have a synchronous diagnosis (0.45%). Table 1 shows characteristics and treatment approach for all patients with 50% receiving CRT and 50% CT alone first. At a median FU of 21.4 months, 2 patients did not complete therapy due to patient choice and both had progression of disease (POD). After completion of CRT, 6 patients underwent rectal surgery with 2 pathological complete response, and 2 patients proceeded with a Watch and Wait approach with clinical complete response on MRI. Prostate boost was delivered equally as often pre-surgery as post-surgery with both SBRT, EBRT and Seed Implant used. There was no grade 3+ RT related toxicity in the patients who completed all therapy.

CONCLUSION

This series represents one of the largest synchronous prostate and rectal cancer cohorts treated with curative intent. Future collaborative work is needed to develop guidelines in the treatment of synchronous prostate and rectal cancers. Although a rare diagnosis, the heterogeneity of approaches has led us to propose a standardized approach to management of synchronous diagnosis with upfront chemotherapy followed by EBRT inclusive of prostate and rectum followed by boost via brachytherapy (SBRT in non-candidates).

Patient-reported Adverse Events During Neoadjuvant Therapy in a Phase 2 Borderline Resectable Pancreatic Cancer Clinical Trial (Alliance A021501)

OBJECTIVE

We sought to evaluate symptomatic adverse event (AE) rates among patients with pancreatic cancer receiving neoadjuvant therapy on clinical trial (A021501) using the Patient-Reported Outcomes Common Terminology Criteria for Adverse Events (PRO-CTCAE).

BACKGROUND

To date, pancreatic cancer clinical trials have measured AEs using standard physician reporting [Common Terminology Criteria for Adverse Events (CTCAE)]. Patient-reported symptomatic AEs have been incompletely characterized.

METHODS

A021501 (December 31, 2016-January 1, 2019) randomized patients with borderline resectable pancreatic ductal adenocarcinoma to 8 doses of mFOLFIRINOX (Arm 1) or 7 doses of mFOLFIRINOX+hypofractionated radiotherapy (Arm 2), followed by pancreatectomy and adjuvant FOLFOX6. Patients completed PRO-CTCAE assessments at baseline, on day 1 of each chemotherapy cycle, and daily during radiotherapy.

RESULTS

Of 126 patients, 96 (76%) initiated treatment and completed a baseline plus at least 1 postbaseline PRO-CTCAE assessment. Diarrhea and fatigue were the only symptomatic grade 3 or higher AEs identified in at least 10% of patients using CTCAE. At least 10% of all patients reported an adjusted PRO-CTCAE composite grade 3 AE during neoadjuvant treatment for 10 of 15 items: anxiety (10%), bloating of abdomen (16%), decreased appetite (18%), diarrhea (13%), dry mouth (21%), fatigue (36%), nausea (18%), generalized pain (16%), abdominal pain (21%), and problems tasting (32%). Decreased appetite was higher in Arm 2 than in Arm 1 ( P =0.0497); no other differences between study arms were observed.

CONCLUSION

Symptomatic AEs during neoadjuvant therapy were common and were reported more frequently by patients using PRO-CTCAE than were recorded by clinicians using standard CTCAE.

Treatment Terminations during Radiation Therapy: A Ten-Year Experience

PURPOSE/OBJECTIVE(S)

Disruptionsin cancer care adversely affect clinical outcomes, particularly when a patient does not complete the prescribed course of treatment. The impact of treatment termination (TT) during radiation therapy has not been well studied. This study addresses TT in a large multi-center department of radiation oncology over a 10-year time period.

MATERIALS/METHODS

TTs of patients undergoing radiation treatment between January 2013 and December 2022 were prospectively tracked as part of departmentalquality and safety monitoring. A TT was defined as the discontinuation of therapy at any point following consent and simulation. Causes of TTs were categorized as: hospice/death, physician choice related to toxicity, physician choice unrelated to toxicity, patient choice related to toxicity, patient choice unrelated to toxicity, progression of disease, non-cancer illness, or other. The rate of TT was calculated as a percentage of all new patients who start radiation treatments. As part of our ongoing department quality and safety program, incremental changes were made to pre-treatment evaluation and scheduling processes, collectively referred to as the "No-Fly" policy. TT rates during three iterations of this policy were compared.

RESULTS

Outof 28,707 planned treatment courses, a total of 1,467 TTs were identified (5.1%). 688 (46.9%) involved patients treated with curative intent, 770 (52.5%) with palliative intent, and 9 (0.6%) for benign disease. The rate of TT decreased from 9.3% in 2013 to 3.3% in 2022. Relative to evolutions of our No-Fly policy, the overall TT rate decreased from 8.8% under No-Fly 1 (2013-2014), to 5.2% during No-Fly 2 (2015-2018), and 4.0% with No-Fly 3 (2019-2022) (ANOVA, p<0.001). The most common sites for TT were H&N (19.3%), CNS (17.9%), and Bone Metastases (17.9%). The most common cause of TT was hospice and/or death (36.5%), 69.1% of which were in patients receiving palliative treatments. Other common causes included patient choice unrelated to toxicity (35%), physician choice unrelated to toxicity (8.8%), and progression of disease (7.6%). There were 473 TTs without radiation dose given (1.6% of planned treatments, 32.3% of TTs).

CONCLUSION

Radiation TTs reflect major deviations from the original care plan. This large cohort study highlights the value of open departmental discourse about TTs, which prompted quality improvement changes that reduced TTs over time. Future studies addressing clinical outcomes can direct treatment decision-making and improve care for our patients.

The Association of Chemoradiation Induced Lymphopenia with Racial Disparity and Its Prognostic Impact on Survival for Anal Cancer

PURPOSE/OBJECTIVE(S)

While the association between chemoradiation induced lymphopenia (CIL) and poor overall survival (OS) is established in multiple solid malignancies, it has not been studied in anal cancer. Racial and socioeconomic disparities as potential predictors of lymphopenia have not been reported. We hypothesize that race and socioeconomic status is associated with increased incidence of severe CIL, which can predict worse overall survival for patients with anal cancer.

MATERIALS/METHODS

A cohort of 75 patients treated with definitive chemoradiation (CRT) for squamous cell anal cancer from January 2014 to December 2020 was reviewed. Total lymphocyte counts (TLC) at baseline and TLC nadir at 1 month post-CRT were analyzed. Logistic regression was used to identify associations between race, gender, ethnicity, median household income by zip code, marital status, baseline hematopoietic cell counts, and post-CRT Grade 3+ lymphopenia (TLC <0.5k/μL). Kaplan-Meier method and Cox regression model were used to perform survival analysis.

RESULTS

Of the 75 patients identified, mean age was 66.9 years and median follow-up time was 37.1 months. There were 63 females, 53 non-Hispanic whites, 22 minorities (12 Blacks, 9 Hispanics, 1 Asians) Radiation dose ranged from 41.4 Gray to 56 Gray. At 1 month post CRT, 85.3% developed lymphopenia (G1 9.3%, G2 26.7%, G3 37.3%, G4 12.0%). On multivariate logistic regression, non-white race demonstrated a trend to have more Grade 3+ lymphopenia (OR = 3.5, p = 0.07). On univariate Cox regression, poorer overall survival was associated with race (HR 3.7, p = 0.04), baseline white blood count (HR 1.3, p = 0.04), baseline hemoglobin (HR 0.6, p = 0.04), and post-CRT Grade 3+ lymphopenia (HR 5.8, p = 0.03). On multivariate Cox regression, only post-CRT Grade 3+ lymphopenia was associated with worse OS (HR 7.5, p = 0.049). 5-year OS significantly differed between patients with and without post-CRT Grade 3+ lymphopenia (62.3% vs 94.7%, P = 0.01).

CONCLUSION

Lymphopenia is commonly observed after chemoradiation for anal cancer. Racial disparity is associated with severe lymphopenia induced by chemoradiation, which is a robust predictor of poor survival in anal cancer. More attention to lymphopenia induced by chemoradiation for anal cancer is needed, particularly in racial minorities.

Effectiveness of the nutrition referral system in a multidisciplinary pancreatic cancer clinic

PURPOSE

Proactive nutrition screening and intervention is associated with improved outcomes for patients with pancreatic adenocarcinoma (PDAC). To better optimize nutrition amongst our PDAC population, we implemented systematic malnutrition screening in the Johns Hopkins pancreas multidisciplinary clinic (PMDC) and assessed the effectiveness of our nutrition referral system.

METHODS

This was a single institution prospective study of patients seen in the PMDC, screened for malnutrition using the Malnutrition Screening Tool (MST) (score range=0 to 5, score > 2 indicates risk of malnutrition), and offered referrals to the oncology dietitian. Patients that requested a referral but did not attend a nutrition appointment were contacted by phone to assess barriers to seeing the dietitian. Univariate (UVA) and multivariable (MVA) analyses were carried out to identify predictors of referral status and appointment completion status.

RESULTS

A total of 97 patients were included in the study, of which 72 (74.2%) requested a referral and 25 (25.8%) declined. Of the 72 patients who requested a referral, 31 (43.1%) attended an appointment with the oncology dietitian. Data on information session attendance was available for 35 patients, of which 8 (22.9%) attended a pre-clinic information session in which the importance of optimal nutrition was highlighted. On MVA, information session attendance was significantly associated with requesting a referral (OR: 11.1, 95% CI 1.12-1.0E3, p=0.037) and successfully meeting with the oncology dietitian (OR: 5.88, 95% CI 1.00-33.3, p=0.049).

CONCLUSION

PMDC teams should institute educational initiatives on the importance of optimal nutrition in order to increase patient engagement with nutrition services.

The Current Role of Radiation in Pancreatic Cancer and Future Directions

Survival outcomes for localized pancreatic adenocarcinoma remains poor. Multimodality therapeutic regimens are critical to maximizing survival outcomes for these patients, which includes the use of systemic therapy, surgery, and radiation. In this review, the evolution of radiation techniques are discussed with a focus on modern techniques such as intensity modulated radiation and stereotactic body radiation therapy. However, the current role of radiation within the most common clinical scenarios for pancreatic cancer in the neoadjuvant, definitive, and adjuvant settings continues to be highly debated. The role of radiation in these settings is reviewed in the context of historical and modern clinical studies. In addition, emerging concepts including dose-escalated radiation, magnetic resonance-guided radiation therapy, and particle therapy are discussed to promote an understanding of how such concepts may change the role of radiation in the future.

Greco-2: A randomized, phase 2 study of stereotactic body radiation therapy (SBRT) in combination with rucosopasem (GC4711) in the treatment of locally advanced or borderline resectable nonmetastatic pancreatic cancer

TPS766

Background: While treatment of pancreatic cancer has advanced, survival rates remain low. Stereotactic body radiotherapy (SBRT; high dose per fraction radiation) may exhibit improved clinical outcomes in locally advanced pancreatic cancer but carries potential gastrointestinal toxicity risks. Rucosopasem (GC4711) is one of a class of investigational selective dismutase mimetics that rapidly and specifically converts superoxide to hydrogen peroxide. Studies have shown that normal cells tolerate hydrogen peroxide fluxes better than cancer cells. As radiation response modifiers, dismutase mimetics have the potential to increase tumor control of SBRT without compromising radiation safety. In a pilot phase 1/2 trial in patients with pancreatic cancer, avasopasem, a dismutase mimetic related to rucosopasem, nearly doubled median overall survival in patients receiving SBRT vs placebo plus SBRT. Improvements versus placebo were also observed in local tumor control, time to metastases, and progression-free survival. Altogether, these data support the hypothesis that rucosopasem may improve survival and the benefit-risk ratio of SBRT by improving efficacy without increasing gastrointestinal toxicity. Methods: GRECO-2 is a phase 2, multicenter, randomized, double-blind, placebo-controlled study (NCT04698915) to determine the effect of adding rucosopasem to SBRT on overall survival in patients with borderline resectable or locally advanced, unresectable nonmetastatic pancreatic cancer following initial chemotherapy with a FOLFIRINOX-based regimen or a gemcitabine doublet. Approximately 160 patients will be randomized (approximately 35 sites) to receive rucosopasem 100 mg or placebo via IV infusion over 15 minutes, prior to each SBRT fraction (5 x 10 Gy). Patients judged to be resectable will undergo surgical exploration within 8 weeks after SBRT. The primary endpoint is overall survival. Secondary endpoints include progression-free survival, locoregional control, time to metastasis, surgical resection rate, RO resection rate, best overall response, in-field local response, and safety (acute and late toxicities). Exploratory endpoints include PRO-CTCAE and CA19-9 normalization. This trial (NCT04698915) is now enrolling. Clinical trial information: NCT04698915 .

Effect of neoadjuvant therapy pathway (NATP) for pancreatic cancer on overall patient outcomes

695

Background: Significant variation exists in the management of potentially resectable pancreatic ductal adenocarcinoma (PDAC) across healthcare systems. We describe the results of a newly implemented neoadjuvant therapy pathway (NATP) in New York’s largest, most diverse health care system. Methods: The NATP was established in June 2019, consisting of a single-day pancreas multi-disciplinary clinic (PMDC) visit, followed by neoadjuvant therapy (NAT), imaging at specific intervals, and PMDC re-reviews at two and four months, prior to consideration of radiation and surgical resection. We conducted an IRB-approved retrospective analysis of patients enrolled in this pathway. Primary endpoints included completion of NATP and overall survival (OS). Results: The cohort consisted of 67 patients reviewed at PMDC and planned for NAT: 45% men, mean age 69.9 years, and 43% non-White between June 2019 and February 2022. Surgical stage at diagnosis was locally advanced (LAPC) 48%, borderline resectable (BRPC) 37% and resectable (RPC) 15%. Of 67 patients, 55 began the NATP (9 transferred care, and 3 declined NAT) and 28 (51%) completed NATP and underwent surgical exploration. Ten completed NATP and did not become surgical candidates, and 2 are still undergoing NAT. NATP was not completed in 15 patients due to 11 metastases (73.3%), 3 deaths (20%) and 1 local progression (6.7%) during NAT. NAT consisted of gemcitabine/nab-paclitaxel (GnP, 28%; 201 total cycles), FOLFIRINOX (45%; 251 total cycles), or a combination of both regimens (26%) with 31 (56%) patients receiving radiotherapy (97% SBRT). Of 28 patients who were explored, 86% underwent successful resection (62.5% R0, 16.7% R1 < 1mm and 20.8% R1). With median follow-up of 12.6 months, there were 17 deaths (31%) and median OS was reached at 20.9 mo (95% CI 10.5, 31.2); GnP vs. FOLFIRINOX median OS were 12.7 mo (95% CI 7.8, 17.6) vs. 26.1 mo (95% CI 9.3, 42.9) (p = 0.026). Median OS was not reached for the resected patients vs.16.3 months for non-resected (p = 0.006). Pathway adherence was seen in 28 (53%), with adherence improving median OS 20.9 mo vs. 16.3 mo (p = 0.039). NATP completion improved median OS 26.1 mo vs. 15.9 mo (p < 0.001). The percentage of patients that remained within the Northwell Health system for their post-NAT was higher among patients in the pathway, compared to prior (87% versus 44%). Conclusions: Implementation of NATP for pancreatic cancer within a single healthcare system increased the percentage of PDAC patients who underwent surgical resection and improved patient retention rate. Our data lay the foundation for further analysis of long-term outcomes of NAT in these patients.

Clinical, dosimetric, and reporting considerations for Y-90 glass microspheres in hepatocellular carcinoma: updated 2022 recommendations from an international multidisciplinary working group

PURPOSE

In light of recently published clinical reports and trials, the TheraSphere Global Dosimetry Steering Committee (DSC) reconvened to review new data and to update previously published clinical and dosimetric recommendations for the treatment of hepatocellular carcinoma (HCC).

METHODS

The TheraSphere Global DSC is comprised of health care providers across multiple disciplines involved in the treatment of HCC with yttrium-90 (Y-90) glass microsphere-based transarterial radioembolization (TARE). Literature published between January 2019 and September 2021 was reviewed, discussed, and adjudicated by the Delphi method. Recommendations included in this updated document incorporate both the results of the literature review and the expert opinion and experience of members of the committee.

RESULTS

Committee discussion and consensus led to the expansion of recommendations to apply to five common clinical scenarios in patients with HCC to support more individualized efficacious treatment with Y-90 glass microspheres. Existing clinical scenarios were updated to reflect recent developments in dosimetry approaches and broader treatment paradigms evolving for patients presenting with HCC.

CONCLUSION

Updated consensus recommendations are provided to guide clinical and dosimetric approaches for the use of Y-90 glass microsphere TARE in HCC, accounting for disease presentation, tumor biology, and treatment intent.

Image Fusion Involving Real-Time Transabdominal or Endoscopic Ultrasound for Gastrointestinal Malignancies: Review of Current and Future Applications

Image fusion of CT, MRI, and PET with endoscopic ultrasound and transabdominal ultrasound can be promising for GI malignancies as it has the potential to allow for a more precise lesion characterization with higher accuracy in tumor detection, staging, and interventional/image guidance. We conducted a literature review to identify the current possibilities of real-time image fusion involving US with a focus on clinical applications in the management of GI malignancies. Liver applications have been the most extensively investigated, either in experimental or commercially available systems. Real-time US fusion imaging of the liver is gaining more acceptance as it enables further diagnosis and interventional therapy of focal liver lesions that are difficult to visualize using conventional B-mode ultrasound. Clinical studies on EUS guided image fusion, to date, are limited. EUS-CT image fusion allowed for easier navigation and profiling of the target tumor and/or surrounding anatomical structure. Image fusion techniques encompassing multiple imaging modalities appear to be feasible and have been observed to increase visualization accuracy during interventional and diagnostic applications.

Using patient flow analysis with real-time patient tracking to optimize radiation oncology consultation visits

PURPOSE

Clinical efficiency is a key component of the value-based care model and a driver of patient satisfaction. The purpose of this study was to identify and address inefficiencies at a high-volume radiation oncology clinic.

METHODS AND MATERIALS

Patient flow analysis (PFA) was used to create process maps and optimize the workflow of consultation visits in a gastrointestinal radiation oncology clinic at a large academic cancer center. Metrics such as cycle times, waiting times, and rooming times were assessed by using a real-time patient status function in the electronic medical record for 556 consults and compared between before vs after implementation of the PFA recommendations.

RESULTS

The initial PFA revealed four inefficiencies: (1) protracted rooming time, (2) inefficient communications, (3) duplicated tasks, and (4) ambiguous clinical roles. We analyzed 485 consult-visits before the PFA and 71 after the PFA. The PFA recommendations led to reductions in overall median cycle time by 21% (91 min vs 72 min, p < 0.001), in cumulative waiting times by 64% (45 min vs 16 min; p < 0.001), which included waiting room time (14 min vs 5 min; p < 0.001) and wait for physician (20 min vs. 6 min; p < 0.001). Slightly less than one-quarter (22%) of consult visits before the PFA lasted > 2 h vs. 0% after implementation of the recommendations (p < 0.001). Similarly, the proportion of visits requiring < 1 h was 16% before PFA vs 34% afterward (p < 0.001).

CONCLUSIONS

PFA can be used to identify clinical inefficiencies and optimize workflows in radiation oncology consultation clinics, and implementing their findings can significantly improve cycle times and waiting times. Potential downstream effects of these interventions include improved patient experience, decreased staff burnout, financial savings, and opportunities for expanding clinical capacity.

Multiagent Chemotherapy and Stereotactic Body Radiation Therapy in Patients with Unresectable Pancreatic Adenocarcinoma: A Prospective Nonrandomized Controlled Trial

PURPOSE

In a prospective multicenter study, gemcitabine monotherapy followed by stereotactic body radiation therapy (SBRT) was well tolerated with outcomes comparable to chemoradiation for locally advanced pancreatic cancer (LAPC). Recent trials have reported improved survival with multiagent chemotherapy (MA-CTX) alone. This prospective trial explored whether SBRT could be safely delivered after MA-CTX. Herein, we report the long-term outcomes of adding SBRT after MA-CTX in LAPC patients and evaluate whether genetic profiles of specimens obtained before SBRT influence outcomes.

METHODS AND MATERIALS

This prospective nonrandomized controlled phase 2 trial enrolled 44 LAPC and 4 locally recurrent patients after multidisciplinary evaluation between 2012 and 2015 at a high-volume pancreatic cancer center. For induction CTX, most received modified FOLFIRINOX (mFFX), or gemcitabine and nab-paclitaxel (GnP) followed by 5-fraction SBRT for all. During fiducial placement, biopsies were obtained with DNA extracted for targeted sequencing using the Memorial Sloan Kettering-Integrated Mutation Profiling of Actionable Cancer Targets platform.

RESULTS

Median induction CTX duration was ≥4 months, and 31 patients received mFFX (65%). Among 44 LAPC patients, 17 (39%) were surgically explored, and 12 of 16 (75%) achieved a R0 resection. Median overall survival (mOS) was 20.2 and 14.6 months from diagnosis and SBRT, respectively. One- and 2-year OS from SBRT was 58% and 28%. The mOS after resection was 28.6 and 22.4 months from diagnosis and SBRT, respectively. Median local progression-free survival was 23.9 and 15.8 months from diagnosis and SBRT, respectively. The mOS for pre-SBRT CA 19-9 ≤180 U/mL versus >180 was 23.1 and 11.3 months, respectively (hazard ratio, 0.53; P = .04). Only 1 patient (2.1%) had late grade ≥2 gastrointestinal toxic effects attributable to SBRT. Despite significant pretreatment with chemotherapy, 88% of tumor specimens were effectively sequenced; survival outcomes were not significantly associated with specific mutational patterns. Quality of life was prospectively collected pre- and post-SBRT with the EORTC QLQ-C30 and PAN26 questionnaires showing no significant change.

CONCLUSIONS

SBRT was safely administered with MA-CTX with minimal toxicity. A high proportion of LAPC patients underwent R0 resection with favorable survival outcomes.

Building a learning network to accelerate improvement in pancreas cancer care and outcomes: Canopy Cancer Collective

368

Background: Pancreas cancer (PC) survival is among the lowest of all malignancies. While limited advances in treatment are a major driver of this reality, ample opportunity exists to improve outcomes by reducing care variation, providingcoordinated, comprehensive care, and accelerating research. Learning health networks (LHNs) improve outcomes in pediatric diseases through such mechanisms, yet are not widely implemented in adult care. We aimed to develop, implement, and collect initial outcomes of the first oncology LHN, the Canopy Cancer Collective (CCC). Methods: In 2019, we established CCC to apply to PC the LHN model, including core tenets of continuous quality improvement (QI), data-sharing, empowered interdisciplinary teams and a stakeholder community including individuals with PC, and focus on community-defined improvable “outcomes that matter”. Six care centers were selected to join the LHN, and engaged in a collaborative design process to co-create a set of improvement aims and change ideas. Center team members received training in basic QI methods/tools guided by the IHI Model for Improvement and were coached to apply these to local improvement efforts. LHN infrastructure and technology enabled sharing of new ideas, best practices, and results amongst centers. Eight more centers joined in 2021, and an outcomes database built and implemented. Results generated by this database will inform center-specific and Network-wide improvement efforts and allow the LHN to undertake research. Results: Currently, 14 care centers are active participants in the CCC LHN. Five key outcomes have been defined as key targets, and centers have co-created and tested change ideas organized around key drivers of excellent PC care including proactive, timely care, aligned/prepared multidisciplinary teams, informed, activated patients, and accurate diagnosis and disease classification. 100% of care centers are trained in QI methods and actively testing change ideas. For example, in May 2022, 11 centers reporting on monthly QI activities met on average 4 times to advance QI projects, deploying a mean of 2.9 plan-do-study-act (PDSA) cycles (range, 0-5) focused on key drivers and outcomes, including reduced time to treatment, increased trial enrollment, assessment of patient experience, and improved data capture. Conclusions: Building a sustainable LHN for PC centers is feasible and has set the stage for improving patient and provider outcomes through iterative community-building, continuous improvement, and sharing of data and multidisciplinary best practices. Results lay the foundation for expansion not only in PC, but translation to other complex malignancies that will benefit from transformative, system-based approaches to outcome improvement.

Optimizing outpatient oncology consult workflow using time-driven activity-based costing: Efficiency and financial impacts

9

Background: Clinical efficiency is a key component of value-based healthcare, patient satisfaction, staff burnout, and institutional operational capacity. The objective of this study was to identify clinic inefficiencies using time driven activity-based costing (TDABC) and evaluate the implementation of a new clinical workflow in high volume, outpatient radiation oncology clinics. Methods: We conducted an IRB-approved quality improvement study in the Gastrointestinal (GI), Genitourinary (GU), and Thoracic Radiation (TRO) Oncology departments at a large academic cancer center and four additional network sites (HALs). TDABC methodology was used to create process maps and optimize consult workflow. Patient encounter metrics were captured utilizing a real-time status function in the electronic medical record (Epic Systems). Anonymous patient satisfaction telephone surveys were administered to patients at the HALs. Hourly wages were determined based on 2021 U.S. Bureau of Labor Statistics. Pre- vs post-implementation metrics were compared using the Mann-Whitney U test. Results: Consult data for 1328 patients pre-intervention and 1234 post-intervention across all sections was included. Median overall cycle time was reduced by 21% in GI (19 min, p < 0.001), 18% in GU (16 min, p < 0.001), and 12% in HALs (9 min, p < 0.001). The median interval between rooming and being seen by the attending physician decreased by 13% in GI (7 min, p < 0.001), 16% in GU (9 min, p < 0.001), 21% in TRO (10 min, p < 0.001), and 9% in HALS (4 min, p < 0.005). For each consult, there was a median financial savings of $29 for GI, $24 for GU, $5 for TRO, and $14 for HALs per consult. From patient satisfaction surveys (95/177), 99% of patients reported their providers spent adequate time with them, 85% reported their appointment began on time, and 91% reported being seen by a care provider in a timely manner. Conclusions: TDABC is a successful method to identify opportunities to improve clinical efficiency. Implementing workflow changes based upon these findings led to substantial reduction in overall encounter cycle times and patient wait times across multiple departments. Furthermore, patient satisfaction was high and there were significant financial savings with the new workflow. These findings may also have implications for reducing staff burnout and expanding clinical capacity across the magnitude of clinical enterprise.[Table: see text]

Association of clinic type with receipt of neoadjuvant therapy among patients with localized pancreatic cancer: Value of multidisciplinary clinic

63

Background: Patients with localized pancreatic adenocarcinoma (PDAC) generally benefit from multi-modality therapy, which may be best coordinated through a pancreas multi-disciplinary clinic (PMDC). Whether treatment practice patterns vary based on whether a patient was seen through PMDC versus individual specialty-specific clinics is unclear. Methods: Using institutional Pancreatic Cancer Registry, we identified patients who came to Johns Hopkins Hospital through either PMDC or one of the individual surgical, medical, or radiation oncology clinics for localized PDAC between 2018-2020 and eventually underwent resection. During this time, it was standard practice for borderline resectable (BRPC) patients to undergo at least 4 months of neoadjuvant chemotherapy, with or without radiation, before transitioning to exploration, while locally advanced (LAPC) patients were treated with 4-6 months of chemotherapy, followed by radiation, followed by potential exploration. The primary outcome was completion of neoadjuvant therapy as per the above stage-specific institutional standards. Multivariable analyses were performed to find association between PMDC visit and completion of neoadjuvant therapy, controlling for age, sex, race, stage, baseline performance status and type of chemotherapy. Results: A total of 240 patients met inclusion criteria. Of these, 157 (65.4%) had PMDC visits. Distribution of stage across the cohort included 81 (34.3%), 91 (38.5%), and 64 (27.1%) patients with resectable PDAC, BRPC and LAPC, respectively. Patients in the PMDC group received radiation therapy more commonly (59.7% vs 34.9%, p = 0.004), as compared to patients seen through individual specialty-specific clinics. Mean duration of chemotherapy was higher for patients seen through PMDC (4.4 (SD: 1.7) vs 3.9 (SD: 2.0) months) compared with individual clinics. Completion of neoadjuvant therapy per institutional stage-specific standards was seen in 46% (n = 24) of the patients visiting individual specialty-specific clinics compared to 71% (n = 85) of patients who were seen through PMDC (p = 0.002). The adjusted odds ratio of completion of neoadjuvant therapy per institutional standards for patients seen through PMDC visit was 3.35 times the odds for patients seen through individual clinics (95% CIs 1.46-7.07; p = 0.004). Of note, a higher proportion of patients who were seen through PMDC enrolled in a clinical trial (n = 26, 16.6%) compared with patients seen through individual clinics (n = 6; 7.2%) (p = 0.043). Conclusions: Provision of care through a multi-disciplinary clinic was associated with significantly higher odds of completing neoadjuvant therapy per institutional standards as compared to care through individual specialty-specific clinics. In addition, care through a PMDC may also be associated with increased trial enrollment.

Mass Transport Model of Radiation Response: Calibration and Application to Chemoradiation for Pancreatic Cancer

PURPOSE

The benefit of radiation therapy for pancreatic ductal adenocarcinoma (PDAC) remains unclear. We hypothesized that a new mechanistic mathematical model of chemotherapy and radiation response could predict clinical outcomes a priori, using a previously described baseline measurement of perfusion from computed tomography scans, normalized area under the enhancement curve (nAUC).

METHODS AND MATERIALS

We simplified an existing mass transport model that predicted cancer cell death by replacing previously unknown variables with averaged direct measurements from randomly selected pathologic sections of untreated PDAC. This allowed using nAUC as the sole model input to approximate tumor perfusion. We then compared the predicted cancer cell death to the actual cell death measured from corresponding resected tumors treated with neoadjuvant chemoradiation in a calibration cohort (n = 80) and prospective cohort (n = 25). After calibration, we applied the model to 2 separate cohorts for pathologic and clinical associations: targeted therapy cohort (n = 101), cetuximab/bevacizumab + radiosensitizing chemotherapy, and standard chemoradiation cohort (n = 81), radiosensitizing chemotherapy to 50.4 Gy in 28 fractions.

RESULTS

We established the relationship between pretreatment computed v nAUC to pathologically verified blood volume fraction of the tumor (r = 0.65; P = .009) and fractional tumor cell death (r = 0.97-0.99; P < .0001) in the calibration and prospective cohorts. On multivariate analyses, accounting for traditional covariates, nAUC independently associated with overall survival in all cohorts (mean hazard ratios, 0.14-0.31). Receiver operator characteristic analyses revealed discrimination of good and bad prognostic groups in the cohorts with area under the curve values of 0.64 to 0.71.

CONCLUSIONS

This work presents a new mathematical modeling approach to predict clinical response from chemotherapy and radiation for PDAC. Our findings indicate that oxygen/drug diffusion strongly influences clinical responses and that nAUC is a potential tool to select patients with PDAC for radiation therapy.

Pancreatic Cancer Patient-derived Organoids Can Predict Response to Neoadjuvant Chemotherapy

OBJECTIVE

To evaluate if patient-derived organoids (PDOs) may predict response to neoadjuvant (NAT) chemotherapy in patients with pancreatic adenocarcinoma.

BACKGROUND

PDOs have been explored as a biomarker of therapy response and for personalized therapeutics in patients with pancreatic cancer.

METHODS

During 2017-2021, patients were enrolled into an IRB-approved protocol and PDO cultures were established. PDOs of interest were analyzed through a translational pipeline incorporating molecular profiling and drug sensitivity testing.

RESULTS

One hundred thirty-six samples, including both surgical resections and fine needle aspiration/biopsy from 117 patients with pancreatic cancer were collected. This biobank included diversity in stage, sex, age, and race, with minority populations representing 1/3 of collected cases (16% Black, 9% Asian, 7% Hispanic/Latino). Among surgical specimens, PDO generation was successful in 71% (15 of 21) of patients who had received NAT prior to sample collection and in 76% (39 of 51) of patients who were untreated with chemotherapy or radiation at the time of collection. Pathological response to NAT correlated with PDO chemotherapy response, particularly oxaliplatin. We demonstrated the feasibility of a rapid PDO drug screen and generated data within 7 days of tissue resection.

CONCLUSION

Herein we report a large single-institution organoid biobank, including ethnic minority samples. The ability to establish PDOs from chemotherapy-naive and post-NAT tissue enables longitudinal PDO generation to assess dynamic chemotherapy sensitivity profiling. PDOs can be rapidly screened and further development of rapid screening may aid in the initial stratification of patients to the most active NAT regimen.

American Radium Society (ARS) Appropriate Use Criteria (AUC) for Locoregional Gastric Adenocarcinoma: Systematic Review and Guidelines

OBJECTIVE

The objective of this study was to systematically evaluate the data regarding the use of neoadjuvant, perioperative, surgical, and adjuvant treatment options in localized gastric cancer patients and to develop Appropriate Use Criteria recommended by a panel of experts convened by the American Radium Society.

METHODS

Preferred reporting items for systematic reviews and meta-analyses methodology was used to develop an extensive analysis of peer-reviewed phase 2/2R/3 trials, as well as meta-analyses found within the Ovid Medline database between 2010 and 2020. The expert panel then rated the appropriateness of various treatments in 5 representative clinical scenarios through a well-established consensus methodology (modified Delphi).

RESULTS

For patients with medically operable locally advanced gastric cancer, the strongest recommendation was for perioperative chemotherapy based on high-quality data. Acceptable alternatives included surgery followed by either chemotherapy or concurrent chemoradiotherapy (CRT). For patients with upfront resection of stages I to III gastric cancer (no neoadjuvant therapy), the group strongly recommended adjuvant therapy with either chemotherapy alone or CRT, based on high-quality data. For patients with locally advanced disease who received preoperative chemotherapy without tumor regression, the group strongly recommended postoperative chemotherapy or postoperative CRT. Finally, for medically inoperable gastric cancer patients, there was moderate consensus recommending definitive concurrent CRT.

CONCLUSIONS

The addition of chemotherapy and/or radiation, either in the neoadjuvant, adjuvant, or perioperative setting, results in improved survival rates for patients compared with surgery alone. For inoperable patients, definitive CRT is a reasonable treatment option, though largely palliative.

Efficacy of Preoperative mFOLFIRINOX vs mFOLFIRINOX Plus Hypofractionated Radiotherapy for Borderline Resectable Adenocarcinoma of the Pancreas: The A021501 Phase 2 Randomized Clinical Trial

Importance

National guidelines endorse treatment with neoadjuvant therapy for borderline resectable pancreatic ductal adenocarcinoma (PDAC), but the optimal strategy remains unclear.

Objective

To compare treatment with neoadjuvant modified FOLFIRINOX (mFOLFIRINOX) with or without hypofractionated radiation therapy with historical data and establish standards for therapy in borderline resectable PDAC.

Design, Setting, and Participants

This prospective, multicenter, randomized phase 2 clinical trial conducted from February 2017 to January 2019 among member institutions of National Clinical Trials Network cooperative groups used standardized quality control measures and included 126 patients, of whom 70 (55.6%) were registered to arm 1 (systemic therapy; 54 randomized, 16 following closure of arm 2 at interim analysis) and 56 (44.4%) to arm 2 (systemic therapy and sequential hypofractionated radiotherapy; all randomized before closure). Data were analyzed by the Alliance Statistics and Data Management Center during September 2021.

Interventions

Arm 1: 8 treatment cycles of mFOLFIRINOX (oxaliplatin, 85 mg/m2; irinotecan, 180 mg/m2; leucovorin, 400 mg/m2; and infusional fluorouracil, 2400 mg/m2) over 46 hours, administered every 2 weeks. Arm 2: 7 treatment cycles of mFOLFIRINOX followed by stereotactic body radiotherapy (33-40 Gy in 5 fractions) or hypofractionated image-guided radiotherapy (25 Gy in 5 fractions). Patients without disease progression underwent pancreatectomy, which was followed by 4 cycles of treatment with postoperative FOLFOX6 (oxaliplatin, 85 mg/m2; leucovorin, 400 mg/m2; bolus fluorouracil, 400 mg/m2; and infusional fluorouracil, 2400 mg/m2 over 46 hours).

Main Outcomes and Measures

Each treatment arm's 18-month overall survival (OS) rate was compared with a historical control rate of 50%. A planned interim analysis mandated closure of either arm for which 11 or fewer of the first 30 accrued patients underwent margin-negative (R0) resection.

Results

Of 126 patients, 62 (49%) were women, and the median (range) age was 64 (37-83) years. Among the first 30 evaluable patients enrolled to each arm, 17 patients in arm 1 (57%) and 10 patients in arm 2 (33%) had undergone R0 resection, leading to closure of arm 2 but continuation to full enrollment in arm 1. The 18-month OS rate of evaluable patients was 66.7% (95% CI, 56.1%-79.4%) in arm 1 and 47.3% (95% CI 35.8%-62.5%) in arm 2. The median OS of evaluable patients in arm 1 and arm 2 was 29.8 (95% CI, 21.1-36.6) months and 17.1 (95% CI, 12.8-24.4) months, respectively.

Conclusions and Relevance

This randomized clinical trial found that treatment with neoadjuvant mFOLFIRINOX alone was associated with favorable OS in patients with borderline resectable PDAC compared with mFOLFIRINOX treatment plus hypofractionated radiotherapy; thus, mFOLFIRINOX represents a reference regimen in this setting.

Trial Registration

ClinicalTrials.gov Identifier: NCT02839343.

Synchronous prostate and rectal cancers across a large distributed healthcare system: Implications for national accreditation program for rectal cancer (NAPRC) guidelines

e15591

Background: Prostate and colorectal cancers are among the most common cancers in men. The prevalence of patients (pts) diagnosed with prostate and rectal cancers at the same time (synchronous) is unknown and guidelines for co-management are not well established despite implications on their co-management. This study aggregated data using several methods across New York’s largest healthcare system, studied the prevalence of synchronous diagnoses, and identified a potential need for prostate specific antigen (PSA) assessment in NAPRC guidelines. Methods: We conducted an IRB approved review of pts using 3 different cohorts from 2010-2021: Northwell Health NAPRC tumor boards, the Oncora radiation oncology database, and the Northwell Health clinical informatics tool Population Analyzer to access electronic health records across the entire Northwell Health System. Synchronous diagnosis was defined as prostate cancer diagnosed during the workup of rectal cancer. Results: Ten pts had synchronous prostate and rectal cancers. Workup of prostate cancer was prompted by elevated PSA alone (n = 3), prostate lesion on rectal cancer staging MRI alone (n = 3), or both (n = 4). Two pts declined recommended treatment (tx). Radiation (RT) volume for pts during neoadjuvant RT included the rectum and prostate. Patients received total neoadjuvant therapy (n = 6) or neoadjuvant chemoRT (n = 4) alone. Three pts had surgery for rectal cancer after neoadjuvant tx. Eight patients received androgen deprivation therapy (n = 8); after neoadjuvant tx pts also had prostate-specific RT (n = 6) or prostate brachytherapy (n = 2). Six pts completed neoadjuvant tx; after a median follow up of 25.9 months 4 pts have no evidence of prostate or rectal cancers. One pt has residual disease with plan for surgical resection; one pt developed new metastases. Median overall survival was 114 months with one death. Among 273 newly diagnosed rectal cancer pts presented at NAPRC tumor boards, there were 122 male pts age ≥ 40 years of which 70% (n = 81) did not have PSA screen at rectal cancer diagnosis. Medical oncologists ordered PSA in 72% (n = 13) of pts not evaluated by primary care. Conclusions: We aggregated data via several methods and performed system wide evaluation of electronic health records across New York State’s largest healthcare system. PSA was not evaluated in a majority of eligible pts. These results support PSA testing in NAPRC guidelines for new rectal cancer diagnosis as it is inexpensive, non-invasive, and may prompt prostate cancer workup. Additionally, 3 pts with prostate cancer did not have prostate lesions on rectal MRI imaging, suggesting a potential role for prostate-protocoled imaging during radiological workup of rectal cancer. Future studies are needed to develop best management of synchronous prostate and rectal cancers due to a lack of consensus guidelines.

Post-radiation neutrophil-to-lymphocyte ratio is a prognostic marker in patients with localized pancreatic adenocarcinoma treated with anti-PD-1 antibody and stereotactic body radiation therapy

PURPOSE

To investigate the role of pre- and post-stereotactic body radiation therapy (SBRT) neutrophil-to-lymphocyte ratio (NLR) in patients with localized pancreatic cancer treated with anti-PD-1 (programmed cell death protein-1) antibody and SBRT.

MATERIALS AND METHODS

This was a retrospective review of 68 patients with borderline resectable or locally advanced pancreatic cancer treated with anti-PD-1 antibody and SBRT after multi-agent chemotherapy. Immunotherapy was administered with 5-fraction SBRT in the neoadjuvant, concurrent, or adjuvant/maintenance setting. Clinical outcomes included overall survival (OS), local progression-free survival, distant metastasis-free survival, and progression-free survival. Median pre- and post-SBRT peripheral blood markers were compared with the Mann-Whitney U test. Univariate and multivariable analyses (UVA and MVA) were performed to identify variables associated with clinical outcomes. Linear regression was performed to determine correlations between variables and peripheral blood markers.

RESULTS

A total of 68 patients were included in the study. The percent change between median pre- and post-SBRT absolute lymphocyte count (ALC), absolute neutrophil count, and NLR were -36.0% (p < 0.001), -5.6% (p = 0.190), and +35.7% (p = 0.003), respectively. Median OS after SBRT was 22.4 months. On UVA, pre-SBRT CA19-9 (hazard ratio [HR] = 1.001; 95% confidence interval [CI], 1.000-1.001; p = 0.031), post-SBRT ALC (HR = 0.33; 95% CI, 0.11-0.91; p = 0.031), and post-SBRT NLR (HR = 1.13; 95% CI, 1.04-1.22; p = 0.009) were associated with OS. On MVA, induction chemotherapy duration (HR = 0.75; 95% CI, 0.57-0.99; p = 0.048) and post-SBRT NLR (HR = 1.14; 95% CI, 1.04-1.23; p = 0.002) predicted for OS. Patients with post-SBRT NLR ≥3.2 had a median OS of 15.6 months versus 27.6 months in patients with post-SBRT NLR <3.2 (p = 0.009). On MVA linear regression, log10CTV had a negative correlation with post-SBRT ALC (regression coefficient = -0.314; 95% CI, -0.626 to -0.003; p = 0.048).

CONCLUSION

Elevated NLR after SBRT is primarily due to depletion of lymphocytes and associated with worse survival outcomes in localized pancreatic cancer treated with anti-PD-1 antibody. Larger CTVs were associated with decreased post-SBRT ALC.

GRECO-2: A randomized, phase 2 study of stereotactic body radiation therapy (SBRT) in combination with rucosopasem (GC4711) in the treatment of locally advanced or borderline resectable nonmetastatic pancreatic cancer

TPS4184

Background: While treatment of pancreatic cancer has advanced, survival rates remain low. Stereotactic body radiotherapy (SBRT; high dose per fraction radiation) may exhibit improved clinical outcomes in locally advanced pancreatic cancer but carries potential gastrointestinal toxicity risks (Zhong 2017). Rucosopasem (GC4711) is one of a class of investigational selective dismutase mimetics that rapidly and specifically converts superoxide to hydrogen peroxide (Riley 2006). Studies have shown that normal cells tolerate hydrogen peroxide fluxes better than cancer cells (Doskey 2016). As radiation response modifiers, dismutase mimetics have the potential to increase tumor control of SBRT without compromising radiation safety (El-Mahdy 2020, Sishc 2021). In a pilot phase 1/2 trial in patients with pancreatic cancer, avasopasem, a dismutase mimetic related to rucosopasem, nearly doubled median overall survival in patients receiving SBRT vs placebo plus SBRT. Improvements versus placebo were also observed in local tumor control, time to metastases, and progression-free survival. Altogether, these data support the hypothesis that rucosopasem may improve survival and the benefit-risk ratio of SBRT by improving efficacy without increasing gastrointestinal toxicity. Materials/Methods: GRECO-2 is a phase 2, multicenter, randomized, double-blind, placebo-controlled study (NCT04698915) to determine the effect of adding rucosopasem to SBRT on overall survival in patients with borderline resectable or locally advanced, unresectable nonmetastatic pancreatic cancer following initial chemotherapy with a FOLFIRINOX-based regimen or a gemcitabine doublet. Approximately 160 patients will be randomized (approximately 35 sites) to receive rucosopasem 100 mg or placebo via IV infusion over 15 minutes, prior to each SBRT fraction (5 x 10 Gy). Patients judged to be resectable will undergo surgical exploration within 8 weeks after SBRT. The primary endpoint is overall survival. Secondary endpoints include progression-free survival, locoregional control, time to metastasis, surgical resection rate, RO resection rate, best overall response, in-field local response, and safety (acute and late toxicities). Exploratory endpoints include PRO-CTCAE and CA19-9 normalization. This trial is now enrolling. Clinical trial information: NCT04698915.

Efficacy and Safety of Reirradiation with Stereotactic Body Radiation Therapy for Locally Recurrent Pancreatic Adenocarcinoma

AIMS

The purpose of this study was to report on outcomes of a cohort of patients who were treated with reirradiation with stereotactic body radiation therapy (SBRT) for locally recurrent pancreatic adenocarcinoma.

MATERIALS AND METHODS

Patients treated with SBRT reirradiation for locally recurrent pancreatic adenocarcinoma from December 2009 to April 2020 were included in the study. Descriptive statistics were used to record patient demographics, tumour and treatment characteristics. Kaplan-Meier analysis was used to evaluate overall survival, local progression-free survival (LPFS), distant metastasis-free survival and progression-free survival (PFS).

RESULTS

In total, 27 patients were included in the study. The median follow-up time from local recurrence was 19.7 months (range 4.2-43.1 months). Most patients received five-fraction SBRT (26/27, 96%). The median overall survival after local recurrence treatment was 18.3 months (range 3.0-42.6 months), with 6-month, 1-year and 2-year overall survival rates of 88.5%, 73.1% and 33.6%. The median LPFS after local recurrence treatment was 16.2 months (range 2.3-33.6 months), with 6-month, 1-year and 2-year LPFS rates of 95.8%, 62.9% and 27.2%. Peri-SBRT chemotherapy improved LPFS (median 17.5 versus 8.5 months; P = 0.010) and overall survival (median 19.3 versus 5.5 months; P = 0.049). Tumours ≤ 3 cm in the greatest dimension showed better local control (median LPFS 19.2 versus 10.2 months; P = 0.130). There was one case (4%) of acute grade 3 pain and one case (4%) of late grade 3 gastrointestinal toxicity.

CONCLUSIONS

Reirradiation with five-fraction SBRT is safe, but local control remains suboptimal. Patients with smaller tumours experienced improved outcomes, as did patients whose treatment plan included the administration of peri-SBRT chemotherapy.

Stereotactic body radiation therapy for the treatment of locally recurrent pancreatic cancer after surgical resection

Background

To report on a cohort of radiation-naïve patients with pancreatic cancer who developed isolated local recurrence following surgical resection and were subsequently treated with stereotactic body radiation therapy (SBRT).

Methods

Patients with pancreatic cancer who were treated with SBRT for isolated local recurrence after surgical resection were retrospectively reviewed. Clinical outcomes were calculated from completion of SBRT and included overall survival (OS), local progression-free survival (LPFS), distant metastasis-free survival (DMFS), and progression-free survival (PFS). Univariate (UVA) analysis was performed to identify variables associated with clinical outcomes. Kaplan-Meier method was used for survival outcomes. Toxicity was assessed using the Common Terminology Criteria for Adverse Events version 4.0.

Results

From September 2012 to November 2018, a total of 19 patients with localized pancreatic cancer were treated with SBRT for isolated local recurrence after initial surgical resection. No patients had prior radiation. The median biologically effective dose (BED10) was 54.8 Gy (range, 37.5-54.8 Gy). Median OS was 17.1 months, with 6-month and 1-year OS rates of 94.4% and 69.6%, respectively. Nine patients (47.4%) developed local failure after SBRT. Pattern of first failure after SBRT was distant in 7 patients (46.7%), local in 5 patients (33.3%), and synchronous distant and local in 3 patients (20.0%). One patient developed local failure after developing distant disease first. Of the 9 local failures, 3 (33.3%) were out-of-field. Median LPFS was 22.2 months, with 6-month and 1-year LPFS rates of 86.9% and 63.2%, respectively. A BED10 <54.8 Gy was associated with inferior LPFS (1-year, 25.0% vs. 80.2%, P<0.009). Median DMFS and PFS were 15.6 months. There was 1 case (5.3 %) of grade 3 gastric perforation. There were no cases of grade 4-5 toxicity events.

Conclusions

SBRT for locally recurrent pancreatic cancer after initial curative resection is safe and feasible. A BED10 <54.8 Gy was significantly associated with inferior local control. Further studies investigating dose escalation and optimal treatment volumes in the locally recurrent setting are warranted.

Location, Location, Location: What Should be Targeted Beyond Gross Disease for Localized Pancreatic Ductal Adenocarcinoma? Proposal of a Standardized Clinical Tumor Volume for Pancreatic Ductal Adenocarcinoma of the Head: The "Triangle Volume"

PURPOSE

In patients with borderline resectable or locally advanced pancreatic adenocarcinoma (BRPC/LAPC), local failure rates after resection remain significant, even in the setting of neoadjuvant chemotherapy and radiation. Suboptimal local control may relate to variable radiation target delineation, as no consensus exists around clinical tumor volume (CTV) design in this context. In the surgical literature, recent attention has been given to the "triangle" volume (TV) as a source of subclinical, residual disease. To understand whether the TV can inform optimal CTV design, we mapped locoregional failures after resection in a large cohort of patients with BRPC/LAPC and compared locations of failure to the TV.

METHODS AND MATERIALS

Patients with BRPC/LAPC of the head or neck diagnosed between 2016 AND 2019 who developed locoregional failure after surgery, neoadjuvant chemotherapy, and radiation were identified. Descriptive statistics were generated to report the frequency of locoregional failures located within the TV and the frequency of new vascular involvement at time of failure, compared with vascular involvement at diagnosis. Additionally, dosimetric coverage of the TV with the preoperative radiation plan that had been used was assessed.

RESULTS

In 31 patients who experienced locoregional failure, the centroid of failure was located within the TV in 28 cases (90%). Extent of vascular involvement at time of locoregional failure included vasculature that had not been involved at diagnosis in 13 cases (42%). The preoperative radiation plan that had been used provided a median V33 Gy and V25 Gy of the TV of only 53% (interquartile range, 34%-72%) and 70% (IQR, 48%-85%), respectively.

CONCLUSIONS

The TV encompassed the vast majority of locoregional failures, but dosimetric coverage of the TV was poor when only targeting gross disease and the full circumference of involved vasculature. As such, the TV may better serve as a basis for CTV design in patients with BRPC/LAPC undergoing neoadjuvant radiation.

Neoadjuvant Stereotactic Body Radiotherapy After Upfront Chemotherapy Improves Pathologic Outcomes Compared With Chemotherapy Alone for Patients With Borderline Resectable or Locally Advanced Pancreatic Adenocarcinoma Without Increasing Perioperative Toxicity

BACKGROUND

Patients with borderline resectable pancreatic cancer (BRPC) or locally advanced pancreatic cancer (LAPC) are at high risk of margin-positive resection. Neoadjuvant stereotactic body radiation therapy (SBRT) may help sterilize margins, but its additive benefit beyond neoadjuvant chemotherapy (nCT) is unclear. The authors report long-term outcomes for BRPC/LAPC patients explored after treatment with either nCT alone or nCT followed by five-fraction SBRT (nCT-SBRT).

METHODS

Patients with BRPC or LAPC from 2011 to 2016 who underwent resection after nCT alone or nCT-SBRT were retrospectively reviewed. Baseline characteristics were compared, and the propensity score with inverse probability weighting (IPW) was used to compare pathologic/survival outcomes.

RESULTS

Of 198 patients, 76 received nCT, and 122 received nCT-SBRT. The nCT-SBRT cohort had a higher proportion of LAPC (53% vs 22%; p < 0.001). The duration of nCT was longer for nCT-SBRT (4.6 vs 2.9 months; p = 0.03), but adjuvant chemotherapy was less frequently administered (53% vs 67.1%; p < 0.001). Adjuvant radiation was administered to 30% of the nCT patients. The nCT-SBRT regimen more frequently achieved negative margins (92% vs 70%; p < 0.001), negative nodes (59% vs 42%; p < 0.001), and pathologic complete response (7% vs 0%; p = 0.02). In the multivariate analysis, nCT-SBRT remained associated with R0 resection (p < 0.001). The nCT-SBRT cohort experienced no significant difference in median overall survival (OS) (22.1 vs 24.5 months), local progression-free survival (LPFS) (13.5 vs. 15.4 months), or distant metastasis-free survival (DMFS) (11.7 vs 16.3 months) after surgery. After SBRT, 1-year OS was 77.0% and 2-year OS was 50.4%. Perioperative Claven-Dindo grade 3 or greater morbidity did not differ significantly between the nCT and nCT-SBRT cohorts (p = 0.81).

CONCLUSIONS

Despite having more advanced disease, the nCT-SBRT cohort was still more likely to undergo an R0 resection and experienced similar survival outcomes compared with the nCT alone cohort.

High local failure rates despite high margin-negative resection rates in a cohort of borderline resectable and locally advanced pancreatic cancer patients treated with stereotactic body radiation therapy following multi-agent chemotherapy

BACKGROUND

Stereotactic body radiation therapy (SBRT) for patients with borderline resectable and locally advanced pancreatic adenocarcinoma (BRPC/LAPC) remains controversial. Herein, we report on surgical, pathologic, and survival outcomes in BRPC/LAPC patients treated at a high-volume institution with induction chemotherapy (CTX) followed by 5-fraction SBRT.

METHODS

BRPC/LAPC patients treated between 2016 and 2019 were retrospectively reviewed. Surgical and pathological outcomes were descriptively characterized. Overall survival (OS) and progression-free survival (PFS) were analyzed using Cox proportional hazard regression. Locoregional failure and distant failure were analyzed with Fine-Gray competing risk model.

RESULTS

Of 155 patients, 91 (59%) had LAPC and 64 (41%) had BRPC. Almost all were treated with induction multi-agent CTX with either FOLFIRINOX (75%) or gemcitabine and nab-paclitaxel (24%) for a median duration of 4.0 months (1-18 months). All received SBRT to a median dose of 33 Gy. Among 64 BRPC patients, 50 (78%) underwent resection, of whom 48 (96%) achieved margin-negative (R0) resection. Among 91 LAPC patients, 57 (63%) underwent resection, of whom 50 (88%) achieved R0 resection. Despite the high R0 rate, 33% of patients experienced locoregional failure, which was a component of 44% of all failures. After SBRT, median OS and PFS were 18.7 and 7.7 months, respectively. After SBRT, 1- and 2-year OS probabilities were 70% and 45%, whereas, from diagnosis, they were 93% and 51%.

CONCLUSIONS

Although a high proportion of BRPC/LAPC patients treated with induction multi-agent CTX followed by SBRT successfully achieved R0 resection, locoregional failure remained common, highlighting the need to continue to optimize radiation delivery in this context.

High neutrophil-to-lymphocyte ratio following stereotactic body radiation therapy is associated with poor clinical outcomes in patients with borderline resectable and locally advanced pancreatic cancer

BACKGROUND

The purpose of this study is to report on the prognostic role of pre- and post-stereotactic body radiation therapy (SBRT) neutrophil-to-lymphocyte ratio (NLR) in a cohort of patients with borderline resectable (BRPC) and locally advanced pancreatic cancer (LAPC) who was treated with multi-agent induction chemotherapy followed by five-fraction SBRT.

METHODS

Patients treated with multi-agent induction chemotherapy followed by SBRT from August 2016 to January 2019 and who had laboratory values available for review were included in the study. Univariate (UVA) and multivariate analyses (MVA) were performed to determine associations between pre-/post-SBRT NLR and overall survival (OS), local progression-free survival (LPFS), distant metastasis-free survival (DMFS), and progression-free survival (PFS).

RESULTS

A total of 156 patients were treated with multi-agent induction chemotherapy followed by SBRT and had laboratory values available for review. On UVA, chemotherapy duration ≥4 months, poorly differentiated disease, inability to undergo resection, pre-SBRT ANC ≥3.7 No./µL, pre-SBRT NLR ≥2.3, and post-SBRT NLR ≥2.6 were associated with worse OS. Patients with post-SBRT NLR ≥2.6 had a median OS of 16.7 months versus median OS not yet reached in patients with post-SBRT <2.6 (P=0.009). On MVA, poorly differentiated disease [hazard ratio (HR) =1.82, 95% CI: 1.04-3.18, P=0.035], inability to undergo resection (HR =2.17, 95% CI: 1.25-3.70, P=0.006), and post-SBRT NLR ≥2.6 (HR =2.55, 95% CI: 1.20-5.45, P=0.015) were associated with inferior OS. On UVA, baseline CA 19-9 ≥219 U/mL, pre-SBRT platelet count ≥157×1,000/µL, and post-SBRT NLR ≥2.6 were associated with inferior LPFS. Patients with post-SBRT NLR ≥2.6 had a median LPFS of 18.3 months versus median LPFS not yet reached in patients with post-SBRT <2.6 (P=0.028). On MVA, only post-SBRT NLR ≥2.6 was associated with worse LPFS (HR =3.22, 95% CI: 1.04-9.98, P=0.043).

CONCLUSIONS

Post-SBRT NLR ≥2.6 predicted for inferior OS and LPFS in BRPC/LAPC patients treated with multi-agent chemotherapy and SBRT. These findings highlight the importance of further elucidating the immunologic effects of radiation therapy in this setting, which may have significant implications on both radiation design as well as combination strategies.

Upfront Chemotherapy Followed by Stereotactic Body Radiation Therapy with or without Surgery in Older Patients with Localized Pancreatic Cancer: A Single Institution Experience and Review of the Literature

OBJECTIVE

To report on clinical outcomes and toxicity in older (age ≥ 70 years) patients with localized pancreatic cancer treated with upfront chemotherapy followed by stereotactic body radiation therapy (SBRT) with or without surgery.

METHODS

Endpoints included overall survival (OS), local progression-free survival (LPFS), distant metastasis-free survival (DMFS), progression-free survival (PFS), and toxicity.

RESULTS

A total of 57 older patients were included in the study. Median OS was 19.6 months, with six-month, one-year, and two-year OS rates of 83.4, 66.5, and 42.4%. On MVA, resection status (HR: 0.30, 95% CI 0.12-0.91, p = 0.031) was associated with OS. Patients with surgically resected tumors had improved median OS (29.1 vs. 7.0 months, p < 0.001). On MVA, resection status (HR: 0.40, 95% CI 0.17-0.93, p = 0.034) was also associated with PFS. Patients with surgically resected tumors had improved median PFS (12.9 vs. 1.6 months, p < 0.001). There were 3/57 cases (5.3%) of late grade 3 radiation toxicity and 2/38 cases (5.3%) of Clavien-Dindo grade 3b toxicity in those who underwent resection.

CONCLUSION

Multimodality therapy involving SBRT is safe and feasible in older patients with localized pancreatic cancer. Surgical resection was associated with improved clinical outcomes. As such, older patients who complete chemotherapy should not be excluded from aggressive local therapy when possible.

Anatomic Criteria Determine Resectability in Locally Advanced Pancreatic Cancer

BACKGROUND

The introduction of multi-agent chemotherapy and radiation therapy has facilitated potential resection with curative intent in selected locally advanced pancreatic cancer (LAPC) patients with excellent outcomes. Nevertheless, there remains a remarkable lack of consensus on the management of LAPC. We sought to describe the outcomes of patients with LAPC and objectively define the multidisciplinary selection process for operative exploration based on anatomical factors.

METHODS

Consecutive patients with LAPC were evaluated for pancreatic surgery in the multidisciplinary clinic of a high-volume institution, between 2013 and 2018. Prospective stratification (LAPC-1, LAPC-2, and LAPC-3), based on the involvement of regional anatomical structures, was performed at the time of presentation prior to the initiation of treatment. Resection rates and patient outcomes were evaluated and correlated with the initial anatomic stratification system.

RESULTS

Overall, 415 patients with LAPC were included in the study, of whom 84 (20%) were successfully resected, with a median overall survival of 35.3 months. The likelihood of operative exploration was associated with the pretreatment anatomic LAPC score, with a resection rate of 49% in patients classified as LAPC-1, 32% in LAPC-2, and 11% in LAPC-3 (p < 0.001). Resected patients with improvement of the LAPC score at the time of exploration had significantly longer median overall survival compared with those with no change or progression of LAPC score (60.7 vs. 29.8 months, p = 0.006).

CONCLUSIONS

Selected patients with LAPC can undergo curative-intent surgery with excellent outcomes. The proposed Johns Hopkins anatomic LAPC score provides an objective system to anticipate the probability of eventual surgical resection after induction therapy.

Vertebral body and splenic irradiation are associated with lymphopenia in localized pancreatic cancer treated with stereotactic body radiation therapy

OBJECTIVES

The purpose of this study was to determine if vertebral body and splenic dosimetry was associated with the development of lymphopenia in patients with borderline resectable (BRPC) and locally advanced pancreatic cancer (LAPC) treated with stereotactic body radiation therapy (SBRT).

METHODS

Patients with BRPC/LAPC who were treated with SBRT and who had lymphocyte counts and radiation treatment plans available for review were included in the study. Vertebral body levels T11-L3 and the spleen were retrospectively contoured for each patient. Univariate (UVA) and multivariable analyses (MVA) were performed to identify associations between vertebral body and splenic dosimetric parameters with absolute lymphocyte count (ALC) and grade ≥ 2 lymphopenia. Receiver operator characteristic curves were generated to identify dose-volume thresholds in predicting grade ≥ 2 lymphopenia.

RESULTS

A total of 132 patients were included in the study. On UVA and MVA, vertebral V15 (regression coefficient [β]: - 0.026, 95% CI - 0.044 to - 0.009, p = 0.003), vertebral V2.5 (β: - 0.011, 95% CI - 0.020 to - 0.002, p = 0.015), and log10PTV (β: - 0.15, 95% CI - 0.30 to - 0.005, p = 0.042) were associated with post-SBRT ALC. On UVA and MVA, vertebral V15 (odds ratio [OR]: 3.98, 95% CI 1.09-14.51, p = 0.027), vertebral V2.5 (OR: 1.04, 95% CI 1.00-1.09, p = 0.032), and spleen V10 (OR: 1.05, 95% CI 1.09-1.95, p = 0.004) were associated with development of grade ≥ 2 lymphopenia. Development of grade ≥ 2 lymphopenia was more likely in patients with vertebral V15 ≥ 5.84% (65.5% vs 34.0%, p = 0.002), vertebral V2.5 ≥ 48.36% (48.9% vs 23.8%, p = 0.005), and spleen V10 ≥ 4.17% (56.2% vs 26.9%, p < 0.001).

CONCLUSIONS

Increasing radiation dose to vertebral bodies and spleen were associated with the development of lymphopenia in BRPC/LAPC treated with SBRT. Optimization of vertebral body and splenic dosimetry may reduce the risk of developing lymphopenia and improve clinical outcomes in this population.

Impact of somatic mutations on clinical and pathologic outcomes in borderline resectable and locally advanced pancreatic cancer treated with neoadjuvant chemotherapy and stereotactic body radiotherapy followed by surgical resection

PURPOSE

The purpose of this study was to determine if somatic mutations are associated with clinical and pathologic outcomes in patients with borderline resectable pancreatic cancer (BRPC) or locally advanced pancreatic cancer (LAPC) who were treated with neoadjuvant chemotherapy and stereotactic body radiotherapy (SBRT).

MATERIALS AND METHODS

Patients treated with neoadjuvant chemotherapy and SBRT followed by surgical resection from August 2016 to January 2019 and who underwent next generation sequencing of their primary tumor were included in the study. Next-generation sequencing was performed either in-house with a Solid Tumor Panel or with FoundationOne CDx. Univariate (UVA) and multivariable analyses (MVA) were performed to determine associations between somatic mutations and pathologic and clinical outcomes.

RESULTS

Thirty-five patients were included in the study. Chemotherapy consisted of modified FOLFIRINOX, gemcitabine and nab-paclitaxel, or gemcitabine and capecitabine. Patients were treated with SBRT in 33 Gy in 5 fractions. On UVA and MVA, tumors with KRAS G12V mutation demonstrated better pathologic tumor regression grade (TRG) to neoadjuvant therapy when compared to tumors with other KRAS mutations (odds ratio = 0.087; 95% confidence interval [CI], 0.009-0.860; p = 0.036). On UVA and MVA, mutations in NOTCH1/2 were associated with worse overall survival (hazard ratio [HR] = 4.15; 95% CI, 1.57-10.95; p = 0.004) and progression-free survival (HR = 3.61; 95% CI, 1.41-9.28; p = 0.008). On UVA, only mutations in NOTCH1/2 were associated with inferior distant metastasis-free survival (HR = 3.38; 95% CI, 1.25-9.16; p = 0.017).

CONCLUSION

In BRPC and LAPC, the KRAS G12V mutation was associated with better TRG following chemotherapy and SBRT. Additionally, NOTCH1/2 mutations were associated with worse overall survival, distant metastasis-free survival, and progression-free survival.

Dosimetric Uncertainties Resulting From Interfractional Anatomic Variations for Patients Receiving Pancreas Stereotactic Body Radiation Therapy and Cone Beam Computed Tomography Image Guidance

PURPOSE

To estimate the effects of interfractional anatomic changes on dose to organs at risk (OARs) and tumors, as measured with cone beam computed tomography (CBCT) image guidance for pancreatic stereotactic body radiation therapy.

METHODS AND MATERIALS

We evaluated 11 patients with pancreatic cancer whom were treated with stereotactic body radiation therapy (33-40 Gy in 5 fractions) using daily CT-on-rails (CTOR) image guidance immediately before treatment with breath-hold motion management. CBCT alignment was simulated in the treatment planning software by aligning the original planning CT to each fractional CTOR image set via fiducial markers. CTOR data sets were used to calculate fractional doses after alignment by applying the rigid shift of the planning CT and CTOR image sets to the planning treatment isocenter and recalculating the fractional dose. Accumulated dose to the gross tumor volume (GTV), tumor vessel interface, duodenum, small bowel, and stomach were calculated by summing the 5 fractional absolute dose-volume histograms into a single dose-volume histogram for comparison with the original planned dose.

RESULTS

Four patients had a GTV D100% of at least 1.5 Gy less than the fractional planned value in several fractions; 4 patients had fractional underestimation of duodenum dose by 1.0 Gy per fraction. The D1.0 cm³ <35 Gy constraint was violated for at least 1 OAR in 3 patients, with either the duodenum (n = 2) or small bowel (n = 1) D1.0 cm³ being higher on the accumulated dose distribution (P = .01). D100% was significantly lower according to accumulated dose GTV (P = .01) and tumor vessel interface (P = .02), with 4 and 2 patients having accumulated D100%  ≥4 Gy lower than the planned value for the GTV and tumor vessel interface, respectively.

CONCLUSIONS

For some patients, CBCT image guidance based on fiducial alignment may cause large dosimetric uncertainties for OARs and target structures, according to accumulated dose.

Stereotactic Versus Conventional Radiation Therapy for Patients With Pancreatic Cancer in the Modern Era

PURPOSE

Patients with pancreatic cancer often receive radiation therapy before undergoing surgical resection. We compared the clinical outcomes differences between stereotactic body radiation therapy (SBRT) and 3-dimensional (3D)/intensity-modulated radiation therapy (IMRT).

METHODS AND MATERIALS

We retrospectively collected data from the University of Texas MD Anderson Cancer Center. Patients with borderline resectable/potentially resectable or locally advanced pancreatic cancer receiving neoadjuvant SBRT (median, 36.0 Gy/5fx), 3D conformal radiation (median, 50.4 Gy/28 fx) or IMRT (median, 50.4 Gy/28 fx) were included. Overall survival (OS) and progression-free survival were analyzed using Cox regression.

RESULTS

In total, 104 patients were included in our study. Fifty-seven patients (54.8%) were treated with SBRT, and 47 patients (45.2%) were treated with 3D/IMRT. Patients in the SBRT group were slightly older (median age: 70.3 vs 62.7 in the 3D/IMRT group). Both groups had similar proportions of patients with locally advanced pancreatic cancer (SBRT: 30, 52.6%; 3D/IMRT: 24, 51.1%). All patients were treated with chemotherapy. Patients in the SBRT group underwent more surgical resection compared with the 3D/IMRT group (38.6% vs 23.4%, respectively). At a median follow-up of 22 months, a total of 60 patients (57.7%) died: 25 (25/57, 43.9%) in the SBRT group, and 35 (35/47, 74.5%) in the 3D/IMRT group. Median OS was slightly higher in the SBRT group (29.6 months vs 24.1 months in the 3D/IMRT group). On multivariable Cox regression, the choice of radiation therapy technique was not associated with differences in OS (adjusted hazard ratios [aHR] = 0.5; 95% confidence interval [CI], 0.2%-1.3%, P = .18). Moreover, patients that underwent surgical resection had better OS (aHR = 0.3, 95% CI, 0.1%-0.8%, P = .01). Furthermore, progression-free survival was also similar between patients treated with SBRT and those treated with 3D/IMRT (aHR = 0.9, 95% CI, 0.5%-1.8%, P = .81).

CONCLUSIONS

SBRT was associated with similar clinical outcomes compared with conventional radiation techniques, despite being delivered over a shorter period of time which would spare patients prolonged treatment burden. Future prospective data are still needed to better assess the role of SBRT in patients with pancreatic cancer.

Advance care planning in patients undergoing surgery to resect pancreatic adenocarcinoma: Underlying tension between balancing hope and realism

BACKGROUND

The timing and the dose of Advanced Care Planning in patients with pancreatic ductal adenocarcinoma undergoing curative-intent resection are generally dictated by the surgeon performing the operation.

METHODS

A qualitative investigation using 1:1 interviews with 40 open-ended questions was conducted with a convenience sample of 10 high-volume pancreatic surgeons from across the country. The grounded theory approach was used for data analysis.

RESULTS

A total of 10 interviews were conducted with expert pancreatic surgeons-6 males and 4 females. During preoperative counseling, all surgeons attempt to motivate patients by emphasizing hope, optimism, and the fact that surgery offers the only opportunity for cure. All surgeons discuss the possibility of recurrence as well as postoperative complications; however, a majority perceived that patients do not fully appreciate the likelihood of recurrence or postoperative complications. All surgeons acknowledged the importance of end-of-life conversations when death is imminent. Seventy percent of surgeons had mixed opinions regarding benefits of preoperative Advanced Care Planning in the preoperative setting, while 20% felt it was definitely beneficial, particularly that delivery of care aligned with patient goals. All surgeons emphasized that Advanced Care Planning should be led by a physician who both knows the patient well and understands the nuances of pancreatic ductal adenocarcinoma management. Most common barriers to in-depth Advanced Care Planning discussion reported by surgeons include taking away hope, lack of time, and concern for sending "mixed messages."

CONCLUSION

We identified that surgeons experience a fundamental tension between promoting realistic long-term goals and expectations versus focusing on hope and enabling an overly optimistic perception of prognosis.