Consensus, debate, and prospective on pancreatic cancer treatments

Pancreatic cancer remains one of the most aggressive solid tumors. As a systemic disease, despite the improvement of multi-modality treatment strategies, the prognosis of pancreatic cancer was not improved dramatically. For resectable or borderline resectable patients, the surgical strategy centered on improving R0 resection rate is consensus; however, the role of neoadjuvant therapy in resectable patients and the optimal neoadjuvant therapy of chemotherapy with or without radiotherapy in borderline resectable patients were debated. Postoperative adjuvant chemotherapy of gemcitabine/capecitabine or mFOLFIRINOX is recommended regardless of the margin status. Chemotherapy as the first-line treatment strategy for advanced or metastatic patients included FOLFIRINOX, gemcitabine/nab-paclitaxel, or NALIRIFOX regimens whereas 5-FU plus liposomal irinotecan was the only standard of care second-line therapy. Immunotherapy is an innovative therapy although anti-PD-1 antibody is currently the only agent approved by for MSI-H, dMMR, or TMB-high solid tumors, which represent a very small subset of pancreatic cancers. Combination strategies to increase the immunogenicity and to overcome the immunosuppressive tumor microenvironment may sensitize pancreatic cancer to immunotherapy. Targeted therapies represented by PARP and KRAS inhibitors are also under investigation, showing benefits in improving progression-free survival and objective response rate. This review discusses the current treatment modalities and highlights innovative therapies for pancreatic cancer.

Clinical outcomes in borderline and locally advanced pancreatic cancer with the addition of low-dose-rate brachytherapy to standard of care therapy

PURPOSE

Surgical resection remains the only curative therapy for pancreatic cancer. Unfortunately, many patients have borderline or unresectable disease at diagnosis due to proximity of major abdominal vessels. Neoadjuvant chemotherapy and radiation are used to down-stage, however, there is a risk that there will be a positive/close surgical margin. The CivaSheet is a low-dose-rate (LDR) brachytherapy device placed at the time of surgery to target the area of highest risk of margin positivity. The purpose of this study is to assess the clinical value of brachytherapy in addition to standard-of-care therapy in pancreatic therapy.

METHODS AND MATERIALS

Between 2017 and 2022 patients with borderline and locally advanced pancreatic cancer treated with neoadjuvant chemotherapy and radiation followed by surgical resection were included. There were 2 cohorts of patients: (1) Those who had the LDR brachytherapy device placed at the time of surgery and (2) those who did not. Sixteen of 19 (84%) patients who had brachytherapy were enrolled in a prospective clinical trial (NCT02843945). Patients were matched for comorbidities, cancer staging, and treatment details. The primary outcome was progression-free survival (PFS).

RESULTS

Thirty-five patients were included in this analysis, 19 in the LDR brachytherapy group and 16 in the comparison cohort. The 2-year PFS was 21% vs. 0% (p = 0.11), 2-year OS was 26% vs. 13% (p = 0.43), and the pancreatic cancer cause-specific survival was 84% vs. 56% (p = 0.13) in favor of the brachytherapy patients.

CONCLUSIONS

Use of LDR brachytherapy at the time of resection shows a trend towards improved progression free and overall survival for patients with borderline or locally advanced pancreatic cancer treated with neoadjuvant chemoradiation.

The Revised R Status is an Independent Predictor of Postresection Survival in Pancreatic Cancer After Neoadjuvant Treatment

OBJECTIVE

To investigate the oncological outcomes of patients with pancreatic ductal adenocarcinoma (PDAC) who had an R 0 or R 1 resection based on the revised R status (1 mm) after neoadjuvant therapy (NAT).

BACKGROUND

The revised R status is an independent prognostic factor in upfront-resected PDAC; however, the significance of 1 mm margin clearance after NAT remains controversial.

METHODS

Patients undergoing pancreatectomy after NAT for PDAC were identified from 2 prospectively maintained databases. Clinicopathological and survival data were analyzed. The primary outcomes were overall survival (OS), recurrence-free survival (RFS), and pattern of recurrence in association with R 0 >1 mm and R 1 ≤1 mm resections.

RESULTS

Three hundred fifty-seven patients with PDAC were included after NAT and subsequent pancreatic resection. Two hundred eight patients (58.3%) received FOLFIRINOX, 41 patients (11.5%) received gemcitabine-based regimens, and 299 individuals (83.8%) received additional radiotherapy. R 0 resections were achieved in 272 patients (76.2%) and 85 patients (23.8%) had R 1 resections. Median OS after R 0 was 41.0 months, compared with 20.6 months after R 1 resection ( P = 0.002), and even longer after additional adjuvant chemotherapy ( R 0 44.8 vs R1 20.1 months; P = 0.0032). Median RFS in the R 0 subgroup was 17.5 months versus 9.4 months in the R 1 subgroup ( P < 0.0001). R status was confirmed as an independent predictor for OS ( R 1 hazard ratio: 1.56, 95% CI: 1.07-2.26) and RFS ( R 1 hazard ratio: 1.52; 95% CI: 1.14-2.0). In addition, R 1 resections were significantly associated with local but not distant recurrence ( P < 0.0005).

CONCLUSIONS

The revised R status is an independent predictor of postresection survival and local recurrence in PDAC after NAT. Achieving R 0 resection with a margin of at least 1 mm should be a primary goal in the surgical treatment of PDAC after NAT.

Pancreatic Ductal Adenocarcinoma: Update of CT-Based Radiomics Applications in the Pre-Surgical Prediction of the Risk of Post-Operative Fistula, Resectability Status and Prognosis

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is the seventh leading cause of cancer-related deaths worldwide. Surgical resection is the main driver to improving survival in resectable tumors, while neoadjuvant treatment based on chemotherapy (and radiotherapy) is the best option-treatment for a non-primally resectable disease. CT-based imaging has a central role in detecting, staging, and managing PDAC. As several authors have proposed radiomics for risk stratification in patients undergoing surgery for PADC, in this narrative review, we have explored the actual fields of interest of radiomics tools in PDAC built on pre-surgical imaging and clinical variables, to obtain more objective and reliable predictors.

METHODS

The PubMed database was searched for papers published in the English language no earlier than January 2018.

RESULTS

We found 301 studies, and 11 satisfied our research criteria. Of those included, four were on resectability status prediction, three on preoperative pancreatic fistula (POPF) prediction, and four on survival prediction. Most of the studies were retrospective.

CONCLUSIONS

It is possible to conclude that many performing models have been developed to get predictive information in pre-surgical evaluation. However, all the studies were retrospective, lacking further external validation in prospective and multicentric cohorts. Furthermore, the radiomics models and the expression of results should be standardized and automatized to be applicable in clinical practice.

Portal Vein or Superior Mesenteric Vein Thrombosis with Dose-Escalated Radiation for Borderline or Locally Advanced Pancreatic Cancer

PURPOSE

Portal vein and superior mesenteric vein thrombosis (PVT/SMVT) are potentially morbid complications of radiation dose-escalated local therapy for pancreatic cancer. We retrospectively reviewed records for patients treated with and without intraoperative radiation (IORT) to identify risk factors for PVT/SMVT.

METHODS

Ninety-six patients with locally advanced or borderline resectable pancreatic adenocarcinoma received neoadjuvant therapy followed by surgical exploration from 2009 to 2014. Patients at risk for close or positive surgical margins received IORT boost to a biologically effective dose (BED10) > 100. Prognostic factors for PVT/SMVT were evaluated using competing risks regression.

RESULTS

Median follow-up was 79 months for surviving patients. Fifty-six patients (58%) received IORT. Twenty-nine patients (30%) developed PVT/SMVT at a median time of 18 months. On univariate competing risks regression, operative blood loss and venous repair with a vascular interposition graft, but not IORT dose escalation or diabetes history, were significantly associated with PVT/SMVT. The development of thrombosis in the absence of recurrence was significantly associated with a longstanding diabetes history, post-neoadjuvant treatment CA19-9, and operative blood loss. All 4 patients who underwent both IORT and vascular repair with a graft developed PVT/SMVT. PVT/SMVT in the absence of recurrence is not associated with significantly worsened overall survival but led to frequent medical interventions.

CONCLUSIONS

Approximately 30% of patients who underwent neoadjuvant chemoradiation for PDAC developed PVT/SMVT a median of 18 months following surgery. This was significantly associated with venous reconstruction with vascular grafts, but not with escalating radiation dose. PVT/SMVT in the absence of recurrence was associated with significant morbidity.

Tolerability, Attrition Rates, and Survival Outcomes of Neoadjuvant FOLFIRINOX for Nonmetastatic Pancreatic Adenocarcinoma: Intent-to-Treat Analysis

BACKGROUND

FOLFIRINOX is increasingly used in the management of pancreatic ductal adenocarcinoma (PDAC). However, neoadjuvant therapy is associated with toxicity, possible disease progression, and biopsy-related and biliary complications that may preclude operative exploration. Data on the true attrition rate outside of clinical trials or resected surgical series are lacking.

STUDY DESIGN

Patients with nonmetastatic PDAC who initiated FOLFIRINOX from 2015 to 2020 were identified from our institution's pharmacy records. Multivariable regression and Cox proportional hazard models were used for adjusted analyses of categorical and survival outcomes, respectively.

RESULTS

Of 254 patients who initiated first-line neoadjuvant FOLFIRINOX, 199 (78.3%) underwent exploration, and 54 (21.3%) did not complete their chemotherapy cycles due to poor tolerability (46.3%), poor response (31.5%), or disease progression (14.8%), among other causes (7.4%). A total of 109 (42.9%) patients experienced grade 3/4 FOLFIRINOX-related toxicity, of whom 73 (28.7%) and 100 (39.4%) required an emergency department visit or inpatient admission, respectively. Finally, not undergoing surgical exploration was associated with impaired overall survival (hazard ratio 7.0; 95% CI 3.8 to 12.8; p < 0.001). Independent predictors of not undergoing exploration were remote history of chemotherapy receipt (odds ratio [OR] 0.06; p = 0.02), inability to complete FOLFIRINOX cycles (OR 0.2, p = 0.003), increase in ECOG score (OR 0.2, p < 0.001), and being single or divorced (OR 0.3, p = 0.018).

CONCLUSIONS

Among 254 patients with nonmetastatic PDAC initiated on FOLFIRINOX, of whom 52% were locally advanced, a total of 199 (78.3%) were explored, 142 (71.4%) underwent successful resection, and 129 (90.8%) were resected with negative margins. Despite 109 (42.9)% of patients experiencing significant toxicity, most patients could be managed through treatment-related complications to complete planned neoadjuvant chemotherapy and undergo planned surgical exploration.

Intraoperative Radiation Therapy for Gastrointestinal Malignancies

Despite improvements in definitive therapy, many patients with gastrointestinal malignancies experience local recurrences or have unresectable disease making subsequent management often challenging and morbid. Although higher doses of radiation may offer improved local control, the ability for dose escalation of external beam radiation therapy is often limited by adjacent radiosensitive structures. Intraoperative radiation therapy allows for additional radiotherapy to be delivered directly to the tumor or areas at highest risk for local recurrence while minimizing toxicity to adjacent structures, offering potentially improved outcomes for patients with unresectable disease or those with a high risk of local recurrence.

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.

Comprehensive multimodal management of borderline resectable pancreatic cancer: Current status and progress

Borderline resectable pancreatic cancer (BRPC) is a complex clinical entity with specific biological features. Criteria for resectability need to be assessed in combination with tumor anatomy and oncology. Neoadjuvant therapy (NAT) for BRPC patients is associated with additional survival benefits. Research is currently focused on exploring the optimal NAT regimen and more reliable ways of assessing response to NAT. More attention to management standards during NAT, including biliary drainage and nutritional support, is needed. Surgery remains the cornerstone of BRPC treatment and multidisciplinary teams can help to evaluate whether patients are suitable for surgery and provide individualized management during the perioperative period, including NAT responsiveness and the selection of surgical timing.

Combined CT and serum CA19-9 for stratifying risk for progression in patients with locally advanced pancreatic cancer receiving intraoperative radiotherapy

Background and purpose

The aim of this study was to evaluate the significance of baseline computed tomography (CT) imaging features and carbohydrate antigen 19-9 (CA19-9) in predicting prognosis of locally advanced pancreatic cancer (LAPC) receiving intraoperative radiotherapy (IORT) and to establish a progression risk nomogram that helps to identify the potential beneficiary of IORT.

Methods

A total of 88 LAPC patients with IORT as their initial treatment were enrolled retrospectively. Clinical data and CT imaging features were analyzed. Cox regression analyses were performed to identify the independent risk factors for progression-free survival (PFS) and to establish a nomogram. A risk-score was calculated by the coefficients of the regression model to stratify the risk of progression.

Results

Multivariate analyses revealed that relative enhanced value in portal-venous phase (REV-PVP), peripancreatic fat infiltration, necrosis, and CA19-9 were significantly associated with PFS (all p < 0.05). The nomogram was constructed according to the above variables and showed a good performance in predicting the risk of progression with a concordance index (C-index) of 0.779. Our nomogram stratified patients with LAPC into low- and high-risk groups with distinct differences in progression after IORT (p < 0.001).

Conclusion

The integrated nomogram would help clinicians to identify appropriate patients who might benefit from IORT before treatment and to adapt an individualized treatment strategy.

Cytoreduction with Hyperthermic Intraperitoneal Chemoperfusion for Pancreatic Cancer with Low-Volume Peritoneal Metastasis: Results from a Prospective Pilot Study

INTRODUCTION

Resection of oligometastatic pancreatic ductal adenocarcinoma (PDAC) has historically been ineffective, however modern systemic chemotherapy has improved survival. Thus, re-evaluating safety and outcomes of surgical resection in selected patients with limited peritoneal metastasis (PM) warrants consideration.

METHODS

From 2018 to 2021, patients with PDAC and positive cytology or limited PM without extraperitoneal metastasis and who had an objective response to ≥ 6 months of systemic chemotherapy were enrolled. Patients underwent laparoscopic hyperthermic intraperitoneal chemotherapy (HIPEC) with cisplatin/mitomycin C. If amenable to a complete cytoreduction, patients went on to cytoreduction and HIPEC.

RESULTS

Overall, 18 patients were enrolled and received a median of 14 (interquartile range [IQR] 12-17) cycles of chemotherapy; 16 (89%) patients received chemoradiation. Laparoscopic HIPEC was completed in 17 patients, with a median length of stay of 1 day, and no grade III complications or hematological toxicities were observed. All 18 patients subsequently underwent a complete cytoreduction (CC-0) along with definitive treatment of the primary tumor, with formal resection (7/18), irreversible electroporation (IRE; 10/18), or intraoperative radiation therapy (IORT; 1/18). Median PCI was 2 (IQR 0-4), median LOS was 7 days (IQR 6-8), and 7 (39%) patients were readmitted. Eight (44%) patients experienced grade 3 or higher complications, including one 30-day mortality. At a median follow-up of 16 months, the median progression-free survival was 20 months and the median overall survival was 26 months.

CONCLUSION

Cytoreduction and HIPEC for selected patients with low-volume PM from PDAC is safe and feasible with favorable short-term outcomes. A phase II trial (NCT04858009) is now enrolling to further assess this multimodality approach in select patients.

Pancreatic cancer - the past, the present, and the future

BACKGROUND

Pancreatic cancer has been and still is associated with a very poor prognosis. This is due to a lack of major breakthroughs with respect to early diagnosis, prognostication, prediction, as well as novel, targeted therapies. The benefits of surgery and chemotherapy are evident, but the fact that only some 10% of all patients have early, localized disease highlights the unmet need for new early detection methods. An improved understanding of tumor biology and the development of molecular markers detectable both in the circulation and in cancer tissues may underlie the development of new tools for optimizing both diagnosis and treatment.

MATERIAL AND METHODS

Review of the literature.

RESULTS AND CONCLUSION

If we do not improve precision oncology for pancreatic ductal adenocarcinoma, the prognosis will still remain dismal and the" burden" on society will increase substantially.

Advances and Remaining Challenges in the Treatment for Borderline Resectable and Locally Advanced Pancreatic Ductal Adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) remains one of the deadliest malignancies in the United States. Improvements in imaging have permitted the categorization of patients according to radiologic involvement of surrounding vasculature, i.e., upfront resectable, borderline resectable, and locally advanced disease, and this, in turn, has influenced the sequence of chemotherapy, surgery, and radiation therapy. Though surgical resection remains the only curative treatment option, recent studies have shown improved overall survival with neoadjuvant chemotherapy, especially among patients with borderline resectable/locally advanced disease. The role of radiologic imaging after neoadjuvant therapy and the potential benefit of adjuvant therapy for borderline resectable and locally advanced disease remain areas of ongoing investigation. The advances made in the treatment of patients with borderline resectable/locally advanced disease are promising, yet disparities in access to cancer care persist. This review highlights the significant advances that have been made in the treatment of borderline resectable and locally advanced PDAC, while also calling attention to the remaining challenges.

Ablative Radiotherapy (ART) for Locally Advanced Pancreatic Cancer (LAPC): Toward a New Paradigm?

Locally advanced pancreatic cancer (LAPC) represents a major urgency in oncology. Due to the massive involvement of the peripancreatic vessels, a curative-intent surgery is generally precluded. Historically, LAPC has been an indication for palliative systemic therapy. In recent years, with the introduction of intensive multi-agent chemotherapy regimens and aggressive surgical approaches, the survival of LAPC patients has significantly improved. In this complex and rapidly evolving scenario, the role of radiotherapy is still debated. The use of standard-dose conventional fractionated radiotherapy in LAPC has led to unsatisfactory oncological outcomes. However, technological advances in radiation therapy over recent years have definitively changed this paradigm. The use of ablative doses of radiotherapy, in association with image-guidance, respiratory organ-motion management, and adaptive protocols, has led to unprecedented results in terms of local control and survival. In this overview, principles, clinical applications, and current pitfalls of ablative radiotherapy (ART) as an emerging treatment option for LAPC are discussed.

Local Control and Survival After Induction Chemotherapy and Ablative Radiation Versus Resection for Pancreatic Ductal Adenocarcinoma With Vascular Involvement

OBJECTIVE

We sought to compare overall survival (OS) and disease control for patients with localized pancreatic ductal adenocarcinoma (PDAC) treated with ablative dose radiotherapy (A-RT) versus resection.

SUMMARY BACKGROUND DATA

Locoregional treatment for PDAC includes resection when possible or palliative RT. A-RT may offer durable tumor control and encouraging survival.

METHODS

This was a single-institution retrospective analysis of patients with PDAC treated with induction chemotherapy followed by A-RT [≥98 Gy biologically effective dose (BED) using 15-25 fractions in 3-4.5 Gy/fraction] or pancreatectomy.

RESULTS

One hundred and four patients received A-RT (49.8%) and 105 (50.2%) underwent resection. Patients receiving A-RT had larger median tumor size after induction chemotherapy [3.2 cm (undetectable-10.9) vs 2.6 cm (undetectable-10.7), P < 0.001], and were more likely to have celiac or hepatic artery encasement (48.1% vs 11.4%, P <0.001), or superior mesenteric artery encasement (43.3% vs 9.5%, P < 0.001); however, there was no difference in the degree of SMV/PV involvement (P = 0.123). There was no difference in locoregional recurrence/progression at 18-months between A-RT and resection; cumulative incidence was 16% [(95% confidence interval (CI) 10%-24%] versus 21% (95% CI 14%-30%), respectively (P= 0.252). However, patients receiving A-RT had a 19% higher 18-month cumulative incidence of distant recurrence/progression [58% (95% CI 48%-67%) vs 30% (95% CI 30%-49%), P= 0.004]. Median OS from completion of chemotherapy was 20.1 months for A-RT patients (95% CI 16.4-23.1 months) versus 32.9 months (95% CI 29.7-42.3 months) for resected patients (P < 0.001).

CONCLUSION

Ablative radiation is a promising new treatment option for PDAC, offering locoregional disease control similar to that associated with resection and encouraging survival.

A phase II trial proposal of total neoadjuvant treatment with primary chemotherapy, stereotactic body radiation therapy, and intraoperative radiation therapy in borderline resectable pancreatic adenocarcinoma

BACKGROUND

The current management guidelines recommend that patients with borderline resectable pancreatic adenocarcinoma (BRPC) should initially receive neoadjuvant chemotherapy. The addition of advanced radiation therapy modalities, including stereotactic body radiation therapy (SBRT) and intraoperative radiation therapy (IORT), could result in a more effective neoadjuvant strategy, with higher rates of margin-free resections and improved survival outcomes.

METHODS/DESIGN

In this single-center, single-arm, intention-to-treat, phase II trial newly diagnosed BRPC will receive a "total neoadjuvant" therapy with FOLFIRINOX (5-fluorouracil, irinotecan and oxaliplatin) and hypofractionated SBRT (5 fractions, total dose of 30 Gy with simultaneous integrated boost of 50 Gy on tumor-vessel interface). Following surgical exploration or resection, IORT will be also delivered (10 Gy). The primary endpoint is 3-year survival. Secondary endpoints include completion of neoadjuvant treatment, resection rate, acute and late toxicities, and progression-free survival. In the subset of patients undergoing resection, per-protocol analysis of disease-free and disease-specific survival will be performed. The estimated sample size is 100 patients over a 36-month period. The trial is currently recruiting.

TRIAL REGISTRATION

NCT04090463 at clinicaltrials.gov.

The Landmark Series: Locally Advanced Pancreatic Cancer and Ablative Therapy Options

Locally advanced pancreatic cancer (LAPC) is a challenging disease to treat. There is consensus that systemic chemotherapy should be the first line of therapy for most patients. However, there is no consensus on how to manage those patients who do not have sufficient response to become candidates for resection but also do not have distant progression after weeks or months of systemic therapy. Radiation therapy is the most commonly used and best-studied local ablative therapy. One recent randomized controlled trial (LAP-07) failed to demonstrate an overall survival benefit for conventional chemoradiation therapy after induction chemotherapy versus chemotherapy alone. This study had several limitations, and ongoing studies are re-evaluating the role of chemoradiation after more effective chemotherapy regimens as well as more advanced radiation techniques. In parallel, there has been increasing interest in other thermal and non-thermal methods of ablation. In particular, irreversible electroporation has gained traction for treatment of LAPC, with at least one ongoing randomized controlled trial designed to address its role compared with systemic chemotherapy alone. Multiple preclinical and clinical studies are investigating combinations of local ablation and immunotherapy with the goal of generating immune responses that will meaningfully improve outcomes.

Intraoperative Radiation Mitigates the Effect of Microscopically Positive Tumor Margins on Survival Among Pancreatic Adenocarcinoma Patients Treated with Neoadjuvant FOLFIRINOX and Chemoradiation

BACKGROUND

Microscopically positive margins (R1) negatively impact survival in pancreatic ductal adenocarcinoma (PDAC). For patients with close/positive margins, intraoperative radiotherapy (IORT) can improve local control. The prognostic impact of an R1 resection in patients who receive total neoadjuvant therapy (TNT; FOLFIRINOX with chemoradiation) and IORT is unknown.

METHODS

Clinicopathologic data were retrospectively collected for borderline/locally advanced (BR/LA) PDAC patients who received TNT and underwent resection between 2011 and 2019. Disease-free (DFS) and overall survival (OS) measured from time of diagnosis were compared between groups.

RESULTS

Two hundred one patients received TNT and were resected, with a median DFS and OS of 24 months and 47 months, respectively. Eighty-eight patients (44%) received IORT; of these, 69 (78%) underwent an R0 and 19 (22%) an R1 resection. There was no significant difference in clinicopathologic factors between the IORT and no-IORT groups, except for resectability status (LA: IORT 69%, no-IORT 53%, p = 0.021) and surgeons' concern for a positive/close margin. R1 resection was associated with worse DFS and OS in the no-IORT population. However, among patients who received IORT, there was no difference in DFS (R0: 29 months, IQR 14-47 vs R1: 20 months, IQR 15-28; p = 0.114) or OS (R0: 48 months, IQR 25-not reached vs R1: 37 months, IQR 30-47; p = 0.307) between patients who underwent R0 vs R1 resection. In multivariate analysis, within the IORT group, R1 resection was not associated with DFS or OS.

CONCLUSION

IORT may mitigate the adverse effect of an R1 resection on DFS and OS in BR/LA PDAC patients receiving TNT.