Social Network Characteristics Associated with More Frequent HIV and STI Prevention Conversations: The N2 Cohort Study in Chicago

Black cisgender sexually minoritized men (SMM) and transgender women (TW) are subgroups at highest risk of HIV and sexually transmitted infections (STIs) in the US. We sought to identify factors facilitating continued conversations - social reinforcement - surrounding HIV/STI prevention among this subgroup. Participants were recruited in Chicago from 2018 to 2019 from community health spaces. Participants provided information about themselves (level 2) and ⩽5 confidants (level 1). We used multinomial multilevel modeling to identify associations with HIV/STI prevention conversation frequency. A total of 370 participants provided information on 987 confidants (mean = 2.6). We found significantly positive associations between having biweekly or more often HIV/STI prevention conversations and a confidant being a kin family member, older by 15 years or more, racially homophilous, and emotionally close. Future interventions should harness social networks by including components that consider racial homophily, respect for elders, and strong ties, in addition to applying kin family systems interventions approaches and decreasing stigma surrounding HIV/STIs.

A phase Ib/II trial of capmatinib plus spartalizumab vs. spartalizumab alone in patients with pretreated hepatocellular carcinoma

Background & aims

This phase Ib/II trial evaluated the safety and efficacy of capmatinib in combination with spartalizumab or spartalizumab alone in patients with advanced hepatocellular carcinoma (HCC).

Methods

Eligible patients who had progressed or were intolerant to sorafenib received escalating doses of capmatinib 200 mg, 300 mg, and 400 mg twice a day (bid) plus spartalizumab 300 mg every 3 weeks (q3w) in the phase Ib study. Once the recommended phase II dose (RP2D) was determined, the phase II study commenced with randomised 1:1 treatment with either capmatinib + spartalizumab (n = 32) or spartalizumab alone (n = 30). Primary endpoints were safety and tolerability (phase Ib) and investigator-assessed overall response rate per RECIST v1.1 for combination vs. single-agent arms using a Bayesian logistic regression model (phase II).

Results

In phase Ib, the RP2D for capmatinib in combination with spartalizumab was determined to be 400 mg bid. Dose-limiting toxicity consisting of grade 3 diarrhoea was reported in one patient at the capmatinib 400 mg bid + spartalizumab 300 mg q3w dose level. The primary endpoint in the phase II study was not met. The observed overall response rate in the capmatinib + spartalizumab arm was 9.4% vs. 10% in the spartalizumab arm. The most common any-grade treatment-related adverse events (TRAEs, ≥20%) were nausea (37.5%), asthenia and vomiting (28.1% each), diarrhoea, pyrexia, and decreased appetite (25.0% each) in the combination arm; TRAEs ≥10% were pruritus (23.3%), and rash (10.0%) in the spartalizumab-alone arm.

Conclusion

Capmatinib at 400 mg bid plus spartalizumab 300 mg q3w was established as the RP2D, with manageable toxicities and no significant safety signals, but the combination did not show superior clinical activity compared with spartalizumab single-agent treatment in patients with advanced HCC who had previously been treated with sorafenib.

Impact and implications

Simultaneous targeting of MET and programmed cell death protein 1 may provide synergistic clinical benefit in patients with advanced HCC. This is the first trial to report a combination of capmatinib (MET inhibitor) and spartalizumab (programmed cell death protein 1 inhibitor) as second-line treatment after sorafenib for advanced HCC. The combination did not show superior clinical activity compared with spartalizumab single-agent treatment in patients with advanced HCC who had previously been treated with sorafenib. The results indicate that there is a clear need to identify a reliable predictive marker of response for HCC and to identify patients with HCC that would benefit from the combination of checkpoint inhibitor +/- targeted therapy.

Clinical trial number

NCT02795429.

First impressions: A prospective evaluation of patient-physician concordance and satisfaction following the initial medical oncology consultation

BACKGROUND

An especially significant event in the patient-oncologist relationship is the initial consultation, where many complex topics-diagnosis, treatment intent, and often, prognosis-are discussed in a relatively short period of time. This study aimed to measure patients' understanding of the information discussed during their first medical oncology visit and their satisfaction with the communication from medical oncologists.

METHODS

Between January and August 2021, patients without prior systemic treatment of their gastrointestinal malignancy (GI) attending the Princess Margaret Cancer Centre (PMCC) were approached within 24 h of their initial consultation to complete a paper-based questionnaire assessing understanding of their disease (diagnosis, treatment plan/intent, and prognosis) and satisfaction with the consultation. Medical oncology physicians simultaneously completed a similar questionnaire about the information discussed at the initial visit. Matched patient-physician responses were compared to assess the degree of concordance.

RESULTS

A total of 184 matched patient-physician surveys were completed. The concordance rates for understanding of diagnosis, treatment plan, treatment intent, and prognosis were 92.9%, 59.2%, 66.8%, and 59.8%, respectively. After adjusting for patient and physician variables, patients who reported treatment intent to be unclear at the time of the consultation were independently associated with lower satisfaction scores (global p = 0.014). There was no statistically significant association between patient satisfaction and whether prognosis was disclosed (p = 0.08).

CONCLUSION

An in-depth conversation as to what treatment intent and prognosis means is reasonable during the initial medical oncology consultation to ensure patients and caregivers have a better understanding about their cancer.

Pembrolizumab as Second-Line Therapy for Advanced Hepatocellular Carcinoma: Longer Term Follow-Up from the Phase 3 KEYNOTE-240 Trial

Introduction

KEYNOTE-240 showed a favorable benefit/risk profile for pembrolizumab versus placebo in patients with sorafenib-treated advanced hepatocellular carcinoma (HCC); however, prespecified statistical significance criteria for overall survival (OS) and progression-free survival (PFS) superiority were not met at the final analysis. Outcomes based on an additional 18 months of follow-up are reported.

Methods

Adults with sorafenib-treated advanced HCC were randomized 2:1 to pembrolizumab 200 mg intravenously every 3 weeks or placebo. Dual primary endpoints were OS and PFS assessed per RECIST v1.1 by blinded independent central review (BICR). Secondary endpoints included objective response rate (ORR), assessed per RECIST v1.1 by BICR, and safety.

Results

413 patients were randomized (pembrolizumab, n = 278; placebo, n = 135). As of July 13, 2020, median (range) time from randomization to data cutoff was 39.6 (31.7-48.8) months for pembrolizumab and 39.8 (31.7-47.8) months for placebo. Estimated OS rates (95% CI) were 17.7% (13.4-22.5%) for pembrolizumab and 11.7% (6.8-17.9%) for placebo at 36 months. The estimated PFS rate (95% CI) for pembrolizumab was 8.9% (5.3-13.6%) and 0% for placebo at 36 months. ORR (95% CI) was 18.3% (14.0-23.4%) for pembrolizumab and 4.4% (1.6-9.4%) for placebo. Immune-mediated hepatitis events did not increase with follow-up. No viral hepatitis flare events were reported.

Conclusion

With extended follow-up, pembrolizumab continued to maintain improvement in OS and PFS and was associated with a consistent adverse event profile compared with placebo in patients with sorafenib-treated advanced HCC. Although KEYNOTE-240 did not meet prespecified statistical significance criteria at the final analysis, these results together with the antitumor activity of second-line pembrolizumab observed in KEYNOTE-224 and the statistically significant and clinically meaningful OS and PFS benefits of second-line pembrolizumab in patients from Asia observed in KEYNOTE-394 reinforce the clinical activity of pembrolizumab in previously treated patients with advanced HCC.

Outcomes of patients with esophageal cancer after allogeneic hematopoietic stem cell transplantation

Background

The improving survival in patients after allogeneic hematopoietic stem cell transplantation (aHCT) has warranted an increased attention to the long-term complications after aHCT especially second malignancies. The risk of developing esophageal cancer is thought to be higher than other malignancies after aHCT. There are limited data on the clinical characteristics, staging, treatment options and outcomes in these patients.

Methods

We retrospectively reviewed all patients who underwent aHCT at our centre over 30 years and identified patients who developed secondary esophageal cancer. Patients were analyzed for transplant details, disease characteristics and therapy, relapse free survival (RFS), and overall survival (OS).

Results

Ten patients [females 40% (n=4); median age 62 years] were diagnosed with esophageal cancer after a median duration of 5.8 years since aHCT. The standardized incidence ratio (SIR) for esophageal ca after aHCT was 1.96. Five patients (55.5%) had advanced clinical stages (stage III-IV) at diagnosis. Esophagectomy (with or without neoadjuvant chemotherapy) was performed in 50% (n=5) patients. Remission was achieved in 70% (n=7) of patients while 1 patient had progressive disease after planned treatment. Progressive disease was the cause in 50% (n=3) of deaths. Estimated 2- and 5-year overall survival after diagnosis of esophageal cancer was 60% and 45% respectively (median survival: 44.1 months).

Conclusions

Despite the higher risk and increased incidence of esophageal cancer after aHCT, the outcomes these patients may be comparable to that in general population if diagnosed early. This implies the need for continued long term follow-up for patients after aHCT with a transplant physician.

Abstract A031: Proteogenomic analysis of the PDAC epithelium reveals tissue markers of subtype identity and biology

Effective treatments for Pancreatic ductal adenocarcinoma (PDAC) remain an urgent need. Integration of molecular PDAC subtypes into clinical trials could enable translational insights into how we might refine existing and emerging therapies to improve treatment options, yet this requires robust clinically suitable marker genes and a better understanding of subtype-related biology. Here, we deeply profiled the molecular composition of human PDAC epithelia and assessed differentially expressed genes for their ability to discriminate between subtypes and mirror their key biological traits. Using well-annotated resected & advanced biospecimens, we mapped the stromal and epithelial landscapes of PDAC subtypes by combining compartment-specific transcriptomics and proteomics with quantitative image analysis of a 42-marker IHC panel and single cell RNA sequencing analyses. The integrated profiling yielded a shortlist of 30 genes that were differentially expressed at both transcriptomic and proteomic levels, and across primary and metastatic sites. These were then scrutinized for their suitability as potential single gene subtype markers through association with subtype-related epithelial and stromal biology and clinical outcomes, and via practical considerations such as immunohistochemical staining quality and cell type-specific expression patterns. Since PDAC subtypes frequently co-occur intratumorally, we furthermore assessed complementarity of different subtype marker combinations and tested association of individual markers with regional subtype biology. Annexin A8 emerged as strong IHC-suitable marker gene of the basal/squamous subtype, that exhibited prognostic and predictive value. Concordantly, Annexin A8 expression was highly correlated with TP63, a master transcription factor for the squamous subtype, and CK5, a well-established basal cell marker. In tissue stains and single cell RNAseq data, Annexin A8 specifically marked malignant epithelia but was absent from adjacent normal acini and stroma cell populations. Annexin A8 expression in PDAC epithelia was spatially distinct from the known classical subtype biomarker GATA6, as well as Claudin 18, which was the top classical/pancreatic progenitor marker gene in our integrated multiOMIC analysis. Furthermore, Annexin A8high tumors as well as Annexin A8high intratumoral regions both recapitulated key biological traits of the basal-like/squamous PDAC subtype, such as increased EMT marker expression, proliferation, hypoxia, macrophage attraction and T cell repulsion. In conclusion, integrated proteogenomic characterization of PDAC subtypes and their tissue features uncovers complementary subtype marker pairs with clinical potential and provides insights into subtype-specific biology with implications in the development of future therapeutic approaches tailored to each PDAC subtype.

Citation Format: Barbara T. Grünwald, Foram Vyas, Michael Geuenich, Nathan Chan, Ricardo Gonzalez, Kazeera Aliar, Niklas Krebs, Antoine Devisme, Geoffroy Andrieux, Gun Ho Jang, Grainne O'Kane, Julie Wilson, Jennifer Knox, Faiyaz Notta, Kieran Campbell, Steven Gallinger, Melanie Boerries, Sandra Fischer, Thomas Kislinger, Rama Khokha. Proteogenomic analysis of the PDAC epithelium reveals tissue markers of subtype identity and biology [abstract]. In: Proceedings of the AACR Special Conference on Pancreatic Cancer; 2022 Sep 13-16; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2022;82(22 Suppl):Abstract nr A031.

Abstract B036: The role of whole genome duplication in progression of pancreatic ductal adenocarcinoma

Introduction: Pancreatic ductal adenocarcinoma (PDA) is a lethal disease that tends to present at an advanced stage, but the evolutionary mechanisms responsible for rapid progression in PDA are poorly understood. Whole genome duplication (WGD) is a hallmark of cancer observed more frequently in late-stage tumors that predicts poorer overall patient survival across cancer types, including PDA. The genome-wide instability that occurs during WGD events can lead to gene dosage imbalances that promote tumor progression and may explain the rapid progression of aneuploidy. Although WGD has been studied extensively in advanced cancer, there is limited data on WGD in primary tumors. We hypothesize that WGD occurs frequently in primary PDA and promotes the rapid progression and high rate of relapse in early stage PDA. We leveraged scWGS to infer copy number profiles and WGD events from tumor cells to determine the rate of subclonal WGD in primary PDA tumors and understand how aneuploidy and genome instability evolve in the earliest stages of tumor progression. Methods: Single cell barcoded libraries from primary treatment naive tumors were prepared with the 10X Genomics Single Cell CNV platform and sequenced to a depth of 20-60x per tumor. Reads were processed using CellRanger DNA pipeline, demultiplexed, and analyzed with Gingko CNV. A total of 10,323 cells from 8 primary PDA tumors (range, 192 – 3146; median = 1286) were recovered, resulting in an average coverage of 0.06x per single cell (range, 0.02x – 0.14x). Results: 5/8 tumors analyzed had evidence of at least one WGD event. The WGD event was identified as a minor subclone in 3 of these 5. Copy number profiles revealed 1-6 distinct subclones in each tumor, demonstrating copy number evolution is ongoing. WGD+ tumors trend towards having higher diversity and higher percentage of genome altered. Conclusion: WGD occurs more frequently in primary PDA than previously understood, and may confer high levels of genetic instability.

Citation Format: Lauren Hummel, Irene Xie, Karen Ng, Amy Zhang, Stephanie Ramotar, Anna Dodd, Grainne O'Kane, Jennifer Knox, Julie Wilson, Steven Gallinger, Faiyaz Notta. The role of whole genome duplication in progression of pancreatic ductal adenocarcinoma [abstract]. In: Proceedings of the AACR Special Conference on Pancreatic Cancer; 2022 Sep 13-16; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2022;82(22 Suppl):Abstract nr B036.

What is the gender representation in authorship in later phase systemic clinical trials in biliary tract cancer (BTC)? - a retrospective review of the published literature

OBJECTIVES

Female physicians in medicine are increasing, but disparities in female authorship exist. The aim of this study was to characterise factors associated with female first (FF) and female senior (SF) authorship in later phase systemic oncological clinical trials in biliary tract cancer (BTC) and identify any changes over time.

SETTING

Embase/Medline identified trial publications in BTC (2000-2020) were included. χ² tests and log regression were used (assessed factors associated with FF and SF authorship, including changes over time (STATA V.16)).

PRIMARY OUTCOME MEASURE

FF and SF authorship in later phase systemic oncological clinical trials in BTC.

SECONDARY OUTCOME MEASURE

Any changes over time?

RESULTS

Of 501 publications, 163 met inclusion criteria. The median percentage of female author representation in publications was 25%; there were no female authors in 13% of publications. Geographic location of the home institution of the first and senior authors was Asia (42%/42%), Europe (29%/29%), USA (24%/22%) and other (4%/6%), respectively. Overall, FF and SF author representation was 20% and 10%, respectively. The median position of the first female author was second in all the publication author lists. The phase of trial, journal-impact factor, industry funding or whether the study met its primary endpoint did not impact FF/SF author representation. More SF authors had home institutions in 'other' geographic locations (40% in 10 trials) (p=0.02) versus Asia (6%), Europe (8%) and USA (14%). There were no significant changes in FF/SF representation over time (p=0.61 and p=0.33 respectively).

CONCLUSIONS

FF and SF author representation in later phase systemic clinical trial publications in BTC is low and has not changed significantly over time. The underlying reasons for this imbalance need to be better understood and addressed.

Correlation of transcriptional subtypes with a validated CT radiomics score in resectable pancreatic ductal adenocarcinoma

OBJECTIVES

Transcriptional classifiers (Bailey, Moffitt and Collison) are key prognostic factors of pancreatic ductal adenocarcinoma (PDAC). Among these classifiers, the squamous, basal-like, and quasimesenchymal subtypes overlap and have inferior survival. Currently, only an invasive biopsy can determine these subtypes, possibly resulting in treatment delay. This study aimed to investigate the association between transcriptional subtypes and an externally validated preoperative CT-based radiomic prognostic score (Rad-score).

METHODS

We retrospectively evaluated 122 patients who underwent resection for PDAC. All treatment decisions were determined at multidisciplinary tumor boards. Tumor Rad-score values from preoperative CT were dichotomized into high or llow categories. The primary endpoint was the correlation between the transcriptional subtypes and the Rad-score using multivariable linear regression, adjusting for clinical and histopathological variables (i.e., tumor size). Prediction of overall survival (OS) was secondary endpoint.

RESULTS

The Bailey transcriptional classifier significantly associated with the Rad-score (coefficient = 0.31, 95% confidence interval [CI]: 0.13-0.44, p = 0.001). Squamous subtype was associated with high Rad-scores while non-squamous subtype was associated with low Rad-scores (adjusted p = 0.03). Squamous subtype and high Rad-score were both prognostic for OS at multivariable analysis with hazard ratios (HR) of 2.79 (95% CI: 1.12-6.92, p = 0.03) and 4.03 (95% CI: 1.42-11.39, p = 0.01), respectively.

CONCLUSIONS

In patients with resectable PDAC, an externally validated prognostic radiomic model derived from preoperative CT is associated with the Bailey transcriptional classifier. Higher Rad-scores were correlated with the squamous subtype, while lower Rad-scores were associated with the less lethal subtypes (immunogenic, ADEX, pancreatic progenitor).

KEY POINTS

• The transcriptional subtypes of PDAC have been shown to have prognostic importance but they require invasive biopsy to be assessed. • The Rad-score radiomic biomarker, which is obtained non-invasively from preoperative CT, correlates with the Bailey squamous transcriptional subtype and both are negative prognostic biomarkers. • The Rad-score is a promising non-invasive imaging biomarker for personalizing neoadjuvant approaches in patients undergoing resection for PDAC, although additional validation studies are required.

Updated efficacy and safety of KEYNOTE-224: a phase II study of pembrolizumab in patients with advanced hepatocellular carcinoma previously treated with sorafenib

OBJECTIVE

Pembrolizumab, a PD-1 inhibitor, demonstrated anti-tumour activity and tolerability in patients treated with sorafenib and with advanced hepatocellular carcinoma in KEYNOTE-224. Longer-term efficacy and safety after ∼2.5 years of additional follow-up are reported.

PATIENTS AND METHODS

Adults with confirmed hepatocellular carcinoma who experienced progression after or intolerance to sorafenib treatment received pembrolizumab 200 mg every 3 weeks for ≤35 cycles or until confirmed progression, unacceptable toxicity, withdrawal of consent or investigator decision. The primary end-point was objective response rate assessed by blinded independent central review per Response Evaluation Criteria in Solid Tumours v1.1. The secondary end-points included duration of response, disease control rate, time to progression, progression-free survival, overall survival and adverse events.

RESULTS

Efficacy and safety were assessed in 104 patients. The median time from first dose to data cutoff was 45.1 months (range, 41.3-49.3). Objective response rate was 18.3% (95% CI: 11.4-27.1), and median duration of response was 21.0 months (range, 3.1 to 39.5+). Disease control rate was 61.5%, and median time to progression was 4.8 months (95% CI: 3.9-7.0). Median progression-free survival was 4.9 months (95% CI: 3.5-6.7) and median overall survival was 13.2 months (95% CI: 9.7-15.3). Of 104 patients, 76 (73.1%) patients reported treatment-related adverse events; most were low grade in severity (grade 3-4, n = 26 [25.0%]; grade 5, n = 1 [1.0%]). Immune-mediated hepatitis occurred in 3 patients (all grade 3). No viral-induced hepatitis flares occurred.

CONCLUSIONS

After ∼2.5 years of additional follow-up, pembrolizumab continued to provide durable anti-tumour activity and no new safety concerns were identified.

CLINICALTRIALS

GOV IDENTIFIER

NCT02702414.

Spatially confined sub-tumor microenvironments in pancreatic cancer

Intratumoral heterogeneity is a critical frontier in understanding how the tumor microenvironment (TME) propels malignant progression. Here, we deconvolute the human pancreatic TME through large-scale integration of histology-guided regional multiOMICs with clinical data and patient-derived preclinical models. We discover "subTMEs," histologically definable tissue states anchored in fibroblast plasticity, with regional relationships to tumor immunity, subtypes, differentiation, and treatment response. "Reactive" subTMEs rich in complex but functionally coordinated fibroblast communities were immune hot and inhabited by aggressive tumor cell phenotypes. The matrix-rich "deserted" subTMEs harbored fewer activated fibroblasts and tumor-suppressive features yet were markedly chemoprotective and enriched upon chemotherapy. SubTMEs originated in fibroblast differentiation trajectories, and transitory states were notable both in single-cell transcriptomics and in situ. The intratumoral co-occurrence of subTMEs produced patient-specific phenotypic and computationally predictable heterogeneity tightly linked to malignant biology. Therefore, heterogeneity within the plentiful, notorious pancreatic TME is not random but marks fundamental tissue organizational units.

ALBI score and outcomes in patients with hepatocellular carcinoma: post hoc analysis of the randomized controlled trial KEYNOTE-240

Aims:

This post hoc analysis evaluated albumin/bilirubin (ALBI) score, an objective measure of liver function, in patients receiving pembrolizumab plus best supportive care (BSC) compared with placebo plus BSC in the KEYNOTE-240 study.

Methods:

Patients with confirmed hepatocellular carcinoma (HCC) and progression after/intolerance to sorafenib, Child–Pugh class A liver function, and Eastern Cooperative Oncology Group performance status of 0–1 were randomly assigned 2:1 to pembrolizumab 200 mg or placebo intravenously every 3 weeks plus BSC for ⩽35 cycles or until confirmed progression/unacceptable toxicity. Outcomes were assessed by ALBI grade.

Results:

Of 413 patients, at baseline 116 had an ALBI grade 1 score (pembrolizumab, n = 74; placebo, n = 42) and 279 had an ALBI grade 2 score (n = 193; n = 86). Change from baseline in ALBI score to the end of treatment was similar in both arms [difference in least squares mean, −0.039; 95% confidence interval (CI): −0.169 to 0.091]. Time to ALBI grade increase was similar in both arms [median for pembrolizumab versus placebo: 7.8 versus 6.9 months; hazard ratio (HR) = 0.863 (95% CI: 0.625–1.192)]. Regardless of baseline ALBI grade, a trend toward improved overall survival was observed with pembrolizumab [grade 1: HR = 0.725 (95% CI: 0.454–1.158); grade 2: HR = 0.827 (95% CI: 0.612–1.119)].

Conclusion:

Pembrolizumab did not adversely impact liver function compared with placebo in patients with HCC, as measured by changes in ALBI scores. A trend toward improved overall survival was observed with pembrolizumab in both ALBI grade groups.

ClinicalTrials.gov identifier: NCT02702401.

Clinical and genomic characterisation of mismatch repair deficient pancreatic adenocarcinoma

OBJECTIVE

To describe the clinical, pathological and genomic characteristics of pancreatic cancer with DNA mismatch repair deficiency (MMRD) and proficiency (MMRP).

DESIGN

We identified patients with MMRD and MMRP pancreatic cancer in a clinical cohort (N=1213, 519 with genetic testing, 53 with immunohistochemistry (IHC)) and a genomic cohort (N=288 with whole-genome sequencing (WGS)).

RESULTS

12 out of 1213 (1.0%) in the clinical cohort were MMRD by IHC or WGS. Of the 14 patients with Lynch syndrome, 3 (21.4%) had an MMRP pancreatic cancer by IHC, and 4 (28.6%) were excluded because tissue was unavailable for testing. MMRD cancers had longer overall survival after surgery (weighted HR after coarsened exact matching 0.11, 95% CI 0.02 to 0.78, p=0.001). One patient with an unresectable MMRD cancer has an ongoing partial response 3 years after starting treatment with PD-L1/CTLA-4 inhibition. This tumour showed none of the classical histopathological features of MMRD. 9 out of 288 (3.1%) tumours with WGS were MMRD. Despite markedly higher tumour mutational burden and neoantigen loads, MMRD cancers were significantly less likely to have mutations in usual pancreatic cancer driver genes like KRAS and SMAD4, but more likely to have mutations in genes that drive cancers with microsatellite instability like ACV2RA and JAK1. MMRD tumours were significantly more likely to have a basal-like transcriptional programme and elevated transcriptional markers of immunogenicity.

CONCLUSIONS

MMRD pancreatic cancers have distinct clinical, pathological and genomic profiles. Patients with MMRD pancreatic cancer should be considered for basket trials targeting enhanced immunogenicity or the unique genomic drivers in these malignancies.

Simulated dose painting of hypoxic sub-volumes in pancreatic cancer stereotactic body radiotherapy

Dose painting of hypoxic tumour sub-volumes using positron-emission tomography (PET) has been shown to improve tumour controlin silicoin several sites, predominantly head and neck and lung cancers. Pancreatic cancer presents a more stringent challenge, given its proximity to critical gastro-intestinal organs-at-risk (OARs), anatomic motion, and impediments to reliable PET hypoxia quantification. A radiobiological model was developed to estimate clonogen survival fraction (SF), using¹⁸F-fluoroazomycin arabinoside PET (FAZA PET) images from ten patients with unresectable pancreatic ductal adenocarcinoma to quantify oxygen enhancement effects. For each patient, four simulated five-fraction stereotactic body radiotherapy (SBRT) plans were generated: (1) a standard SBRT plan aiming to cover the planning target volume with 40 Gy, (2) dose painting plans delivering escalated doses to a maximum of three FAZA-avid hypoxic sub-volumes, (3) dose painting plans with simulated spacer separating the duodenum and pancreatic head, and (4), plans with integrated boosts to geometric contractions of the gross tumour volume (GTV). All plans saturated at least one OAR dose limit. SF was calculated for each plan and sensitivity of SF to simulated hypoxia quantification errors was evaluated. Dose painting resulted in a 55% reduction in SF as compared to standard SBRT; 78% with spacer. Integrated boosts to hypoxia-blind geometric contractions resulted in a 41% reduction in SF. The reduction in SF for dose-painting plans persisted for all hypoxia quantification parameters studied, including registration and rigid motion errors that resulted in shifts and rotations of the GTV and hypoxic sub-volumes by as much as 1 cm and 10 degrees. Although proximity to OARs ultimately limited dose escalation, with estimated SFs (∼10^-5) well above levels required to completely ablate a ∼10 cm³tumour, dose painting robustly reduced clonogen survival when accounting for expected treatment and imaging uncertainties and thus, may improve local response and associated morbidity.

Second-line cabozantinib after sorafenib treatment for advanced hepatocellular carcinoma: a subgroup analysis of the phase 3 CELESTIAL trial

Objective

In the phase 3 CELESTIAL trial, cabozantinib improved overall survival (OS) and progression-free survival (PFS) compared with placebo in patients with previously treated advanced hepatocellular carcinoma (HCC). This subgroup analysis evaluated cabozantinib in patients who had received sorafenib as the only prior systemic therapy.

Methods

CELESTIAL randomised (2:1) patients with advanced HCC and Child–Pugh class A liver function to treatment with cabozantinib (60 mg daily) or placebo. Eligibility required prior treatment with sorafenib, and patients could have received ≤2 prior systemic regimens. The primary endpoint was OS. Outcomes in patients who had received sorafenib as the only prior therapy were analysed by duration of prior sorafenib (<3 months, 3 to <6 months and ≥6 months).

Results

Of patients who had received only prior sorafenib, 331 were randomised to cabozantinib and 164 to placebo; 136 patients had received sorafenib for <3 months, 141 for 3 to <6 months and 217 for ≥6 months. Cabozantinib improved OS relative to placebo in the overall second-line population who had received only prior sorafenib (median 11.3 vs 7.2 months; HR=0.70, 95% CI 0.55 to 0.88). This improvement was maintained in analyses by prior sorafenib duration with longer duration generally corresponding to longer median OS—median OS 8.9 vs 6.9 months (HR=0.72, 95% CI 0.47 to 1.10) for prior sorafenib <3 months, 11.5 vs 6.5 months (HR=0.65, 95% CI 0.43 to 1.00) for 3 to <6 months and 12.3 vs 9.2 months (HR=0.82, 95% CI 0.58 to 1.16) for ≥6 months. Cabozantinib also improved PFS in all duration subgroups. Safety data were consistent with the overall study population.

Conclusion

Cabozantinib improved efficacy outcomes versus placebo in the second-line population who had received only prior sorafenib irrespective of duration of prior sorafenib treatment, further supporting the utility of cabozantinib in the evolving treatment landscape of HCC.

Clinical trial number

NCT01908426.

Abstract 1193: Digital quantification of GATA6 expression from immunohistochemistry is associated with overall survival after surgery for pancreatic cancer in the ESPAC trials

Introduction: GATA6, a transcription factor involved in pancreaticogenesis, correlates with major transcriptomic subtypes of pancreatic cancer, and early evidence suggests a potential role as a prognostic biomarker. In this study, we tested whether semi-automated digital quantification of GATA6 immunohistochemistry (IHC) was associated with overall survival (OS) after surgical resection of pancreatic cancer in randomized trials of adjuvant chemotherapy.

Materials and Methods: Tissue microarrays of pancreatic adenocarcinoma specimens were stained for GATA6 expression using IHC. Specimens came from patients in the ESPAC-3 and ESPAC-4 randomized phase III trials comparing adjuvant chemotherapy regimens. Two pathologists blinded to clinical data independently assessed GATA6 protein expression in cores using a customized computer algorithm from the open-source digital pathology software QuPath. Briefly, the digital assistant provided GATA6 IHC semiquantitative scores (0-4) for individual cells, which were made available to the pathologist for review. This semi-automated digital quantification of GATA6 expression was compared to manual quantification as previously reported (Grant et al., AACR Pancreatic Cancer, 2020). Concordance between pathologists across tissue cores was calculated using a weighted kappa statistic for scores 0 through 4, and an unweighted kappa statistic for high (3-4) and low (0-2) expression levels. Discrepancies were resolved through consensus. Median OS was estimated in GATA6 high and low subgroups using Kaplan-Meier curves. OS was compared using Cox proportional hazard regressions adjusting for adjuvant chemotherapy treatment, lymph node status, and post-operative CA-19-9.

Results: GATA6 expression was quantified in 230 patients using the semi-automated digital and manual approaches. Inter-observer concordance markedly improved with digital assistance compared to the manual approach (weighted kappa statistic across all scores 0.69 versus 0.41, unweighted kappa statistic comparing high and low expression 0.71 versus 0.25). GATA6 expression measured using the semi-automated digital approach was significantly associated with OS: median OS was 25.7 months in GATA6 low cancers versus 42.4 months in GATA6 high cancers, with an adjusted hazard ratio of 1.58 (95% confidence interval 1.10-2.28, P=0.014).

Conclusion: GATA6 IHC is a prognostic biomarker for pancreatic cancers treated with surgical resection and adjuvant chemotherapy that can be consistently and reliably quantified using digital assistance.

Citation Format: Robert C. Grant, Kai Duan, Richard Jackson, William Greenhalf, Eithne Costello-Goldring, Paula Ghaneh, Christopher Halloran, Daniel Palmer, Thilo Hackert, Markus Buchler, Shawn Hutchison, Stephanie Ramotar, Anna Dodd, Julie Wilson, Faiyaz Notta, Grainne O'Kane, Jennifer Knox, John Neoptolemos, Steven Gallinger, Sandra Fischer. Digital quantification of GATA6 expression from immunohistochemistry is associated with overall survival after surgery for pancreatic cancer in the ESPAC trials [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1193.

Prognostic value of early changes in CT-measured body composition in patients receiving chemotherapy for unresectable pancreatic cancer

OBJECTIVES

Skeletal muscle mass is a prognostic factor in pancreatic ductal adenocarcinoma (PDAC). However, it remains unclear whether changes in body composition provide an incremental prognostic value to established risk factors, especially the Response Evaluation Criteria in Solid Tumors version 1.1 (RECISTv1.1). The aim of this study was to determine the prognostic value of CT-quantified body composition changes in patients with unresectable PDAC starting chemotherapy.

METHODS

We retrospectively evaluated 105 patients with unresectable (locally advanced or metastatic) PDAC treated with FOLFIRINOX (n = 64) or gemcitabine-based (n = 41) first-line chemotherapy within a multicenter prospective trial. Changes (Δ) in skeletal muscle index (SMI), subcutaneous (SATI), and visceral adipose tissue index (VATI) between pre-chemotherapy and first follow-up CT were assessed. Cox regression models and covariate-adjusted survival curves were used to identify predictors of overall survival (OS).

RESULTS

At multivariable analysis, adjusting for RECISTv1.1-response at first follow-up, ΔSMI was prognostic for OS with a hazard ratio (HR) of 1.2 (95% CI: 1.08-1.33, p = 0.001). No significant association with OS was observed for ΔSATI (HR: 1, 95% CI: 0.97-1.04, p = 0.88) and ΔVATI (HR: 1.01, 95% CI: 0.99-1.04, p = 0.33). At an optimal cutoff of 2.8 cm²/m² per 30 days, the median survival of patients with high versus low ΔSMI was 143 versus 233 days (p < 0.001).

CONCLUSIONS

Patients with a lower rate of skeletal muscle loss at first follow-up demonstrated improved survival for unresectable PDAC, regardless of their RECISTv1.1-category. Assessing ΔSMI at the first follow-up CT may be useful for prognostication, in addition to routine radiological assessment.

KEY POINTS

• In patients with unresectable pancreatic ductal adenocarcinoma, change of skeletal muscle index (ΔSMI) in the early phase of chemotherapy is prognostic for overall survival, even after adjusting for Response Evaluation Criteria in Solid Tumors version 1.1 (RECISTv1.1) assessment at first follow-up. • Changes in adipose tissue compartments at first follow-up demonstrated no significant association with overall survival. • Integrating ΔSMI into routine radiological assessment may improve prognostic stratification and impact treatment decision-making at the first follow-up.

A Risk Score Model for Locoregional Recurrence Following Upfront Surgery for Pancreatic Adenocarcinoma: Implications for Adjuvant Therapy

AIMS

The aims of the study were to identify predictors of locoregional failure (LRF) following surgery for pancreatic adenocarcinoma, develop a prediction risk score model of LRF and evaluate the impact of postoperative radiation therapy (PORT) on LRF.

MATERIALS AND METHODS

A retrospective review was conducted on patients with stages I-III pancreatic adenocarcinoma who underwent surgery at our institution (2005-2016). Univariable and then multivariable analyses were used to evaluate clinicopathological factors associated with LRF for patients who did not receive PORT. The risk score of LRF was calculated based on the sum of coefficients of the predictors of LRF. The model was applied to the entire cohort to evaluate the impact of PORT on the high- and low-risk groups for LRF.

RESULTS

In total, 467 patients were identified (median follow-up 22 months). Among patients who did not receive PORT (n = 440), predictors of LRF were pN+, involved or close ≤1 mm margin(s), moderately and poorly differentiated tumour grade and lymphovascular invasion. After adding patients who received PORT, the 2-year LRF in the high-risk group was 57% for patients who did not receive PORT (n = 242) and 32% among patients who received PORT (n = 22), with an absolute benefit to LRF of 25% (95% confidence interval 5-52%, P = 0.07). The 2-year overall survival for the high-versus the low-risk group was 36% versus 67% (P < 0.001).

CONCLUSION

This risk group classification could be used to identify pancreatic adenocarcinoma patients with higher risk of LRF who may benefit from PORT. However, validation and prospective evaluation are warranted.

A48 USE OF ENDOSCOPIC ULTRASOUND FINE NEEDLE ASPIRATE AND ENDOSCOPIC ULTRASOUND FINE NEEDLE BIOPSY FOR DETECTION OF GATA6 EXPRESSON IN PANCREATIC DUCTAL ADENOCARINCOMA

Background

GATA6 is a transcription factor that can be used to distinguish between the basal-like and classical subtypes of pancreatic ductal adenocarcinoma (PDAC). The basal-like subtype has been demonstrated to be less responsive to modified FOLFIRINOX chemotherapy and thus can be used to predict response to specific chemotherapies. To date, GATA6 expression has only been evaluated in surgically resected PDAC specimens. Less than 15% of patients with PDAC are eligible for surgery. Endoscopic ultrasound guided fine-needle aspirate (EUS-FNA) and biopsy (EUS-FNB) can potentially help assess GATA6 expression in PDAC and in turn, help guide personalized treatment selection in all cases of PDAC.

Aims

The primary objective of this study was to explore the yield of EUS-FNA and EUS-FNB for the detection of GATA6 among patients with PDAC. The study also aimed to explore the impact of lesion location on sample adequacy and type of fixative on validity of GATA6 staining.

Methods

This study was conducted from November 2017 to October 2019. Consecutive patients with a diagnosis of PDAC confirmed by biopsy were included. Patients underwent either EUS-FNB or EUS-FNA to obtain tissues samples. Samples were fixed in either neutral buffered formalin (NBF) or a methanol based buffered solution (Cytolyt) and evaluated by a specialized cytopathology team. Fisher’s exact test was used and a p-value ≤0.05 was considered to indicate statistical significance.

Results

Forty-four patients were included in the study. Twenty-three (52%) patients were male and the median age of patients was 67.5 years. Twenty-five lesions were located in the head and neck of the pancreas, 14 were located in the body, and 4 were located in the tail. One patient was found to have a local recurrence of PDAC at the surgical bed of a previous Whipple procedure.

Eighteen lesions were sampled by EUS-FNA and 26 were sampled using EUS-FNB. Thirty-eight (86%) samples were adequate for assessment of GATA6. Sampling technique (p=0.68) and fixative type (p=1.00) did not appear to affect sample adequacy. Compared to pancreatic body or tail specimens, samples obtained from the head or neck of the pancreas were more likely to be inadequate for analysis (p=0.03).

Conclusions

EUS-FNA and EUS-FNB samples are efficacious methods of assessing GATA6 expression in PDAC. This is the first predictor of treatment response that has been demonstrated to be obtained without surgical resection. Neither EUS needle type or alcohol fixation before cell block preparation appear to impact GATA6 detection. Lesions in the pancreatic head or neck appear to be associated with higher rates of sample inadequacy. Larger, prospective studies are required to confirm our findings.

Funding Agencies

None

Adherence to Pre-exposure Prophylaxis in Black Men Who Have Sex with Men and Transgender Women in a Community Setting in Harlem, NY

While oral pre-exposure prophylaxis (PrEP) has proven efficacious for HIV prevention, consistent use is necessary to achieve its intended impact. We compared effectiveness of enhanced PrEP (enPrEP) adherence support to standard of care (sPrEP) among Black MSM and TGW attending a community clinic in Harlem, NY. EnPrEP included peer navigation, in-person/online support groups, and SMS messages. Self-reported adherence over previous 30 days, collected in quarterly interviews, was defined as ≥ 57%. Crude and adjusted analyses examined factors associated with adherence. A total of 204 participants were enrolled and randomized; 35% were lost to follow-up. PrEP adherence was 30% at 12-months; no intervention effect was observed (p = 0.69). Multivariable regression analysis found that lower adherence was associated with low education and depressive symptoms. We found that an enhanced adherence intervention did not improve PrEP adherence. Findings point to the need for innovative methods to improve PrEP adherence among Black MSM and TGW.Clinical Trial Registration NCT02167386, June 19, 2014.

Abstract PO-005: GATA6 expression is prognostic after surgical resection of pancreatic cancer: results from the ESPAC trials

Introduction No biomarker is clinically available to predict prognosis after surgical resection of pancreatic cancer beyond CA-19-9, a classical tumor marker. GATA6 is a transcription factor necessary for pancreaticogenesis that associates with the major transcriptomic subtypes of pancreatic cancer. In this study, we evaluated the prognostic utility of GATA6 expression in randomised adjuvant chemotherapy trials. Materials and Methods We retrospectively analyzed resection specimens in tissue microarrays from patients who participated in two international randomized phase III trials of adjuvant chemotherapy after resection of pancreatic ductal adenocarcinoma: ESPAC-3, which compared fluorouracil plus folinic acid with gemcitabine; and ESPAC-4, which compared gemcitabine plus capecitabine with gemcitabine alone. GATA6 expression was measured using immunohistochemistry. Expression levels from 0 to 4 were scored through consensus between two pathologists who were blinded to clinical characteristics and outcome. Concordance on each tissue core was assessed using a weighted kappa score. Overall survival (OS) was assessed using Kaplan-Meier curves and compared between GATA6 expression levels using univariate Cox proportional hazard regression models and multivariate models that adjusted for lymph node status, post-operative CA-19-9, and treatment arms. After an initial analysis of all five levels, expression levels were regrouped into low (0-2) and high (3-4). Our primary objective was to assess for a prognostic association between GATA6 and OS. Secondary analyses considered predictive associations with the addition of capecitabine to gemcitabine using an interaction term, and associations with baseline characteristics using Wilcoxon and Fisher-exact tests. Results: 26 patients from ESPAC-3 and 205 patients from ESPAC-4 were included. 7, 18, 130, 74, and 2 patients had GATA6 expression levels of 0, 1, 2, 3, and 4, respectively. Concordance between pathologists was moderate (weighted kappa 0.41). GATA6 expression was significantly associated with overall survival when regrouped into low (0–2, N=155) and high (3–4, N=76) expression. Low GATA6 expression was associated with shorter OS (median OS 26.1 months, 95% confidence interval (CI) 22.9–30.4 versus 42.4 months, 95% CI 30.2–56.5, univariate hazard ratio (HR) 1.70, 95% CI 1.31–2.41, P=0.002), which persisted after adjustment for potential confounders (multivariate HR 1.57, 95% CI 1.09–2.62, P=0.016). GATA6 expression was not significantly associated with baseline characteristics or predictive of differential benefit from the addition of capecitabine to gemcitabine. Conclusion: Low GATA6 expression is significantly associated with inferior OS after surgical resection of pancreatic cancer. Future research will automate the measurement of GATA6 expression using image analyses.

Citation Format: Robert C. Grant, Kai Duan, Richard Jackson, William Greenhalf, Eithne Costello-Goldring, Paula Ghaneh, Christopher Halloran, Daniel Palmer, Thilo Hackert, Markus Buchler, Shawn Hutchison, Stephanie Ramotar, Anna Dodd, Julie Wilson, Faiyaz Notta, Grainne O'Kane, Jennifer Knox, John Neoptolemos, Steven Gallinger, Sandra Fischer. GATA6 expression is prognostic after surgical resection of pancreatic cancer: results from the ESPAC trials [abstract]. In: Proceedings of the AACR Virtual Special Conference on Pancreatic Cancer; 2020 Sep 29-30. Philadelphia (PA): AACR; Cancer Res 2020;80(22 Suppl):Abstract nr PO-005.

Abstract PR-002: Stromal phenotypic heterogeneity fosters pancreatic cancer progression

Pancreatic ductal adenocarcinoma (PDAC) remains mostly untreatable while its incidence is on the rise. PDAC stroma should be a reservoir for novel therapeutic targets. Yet, stromal cellular complexity and an extensive intratumoral heterogeneity in human patients have left the functions of PDAC stroma poorly understood and likely hamper its targeting. Here, we set out to deconvolute regional heterogeneity in human PDAC stroma and assess its role in disease progression. Using resected & advanced biospecimens with known patient outcome, we mapped the stromal and epithelial landscapes of PDAC by combining integrative histopathology, quantitative image analysis of a 30-marker IHC panel, genomics and proteomics, machine learning, scRNAseq of PDAC-derived fibroblasts, and controlled functional assays. This histology-guided multidimensional approach revealed two overarching types of sub-tumormicroenvironments (subTMEs) in PDAC, present across stages and primary and metastatic sites. These subTMEs co-occurred intratumourally but were spatially confined, producing patient-specific cellular and molecular heterogeneity in PDAC stroma. SubTME-resolved IHC characterization of PDAC specimens and multiplexed functional analyses with subTME-specific patient-derived fibroblasts and organoids then identified how both microenvironmental programs were uniquely structured to support crucial aspects of tumour biology. Forming a complementary stromal support system, reactive subTME regions rich in fibroblasts and immune cells were vascularized and promoted features of aggressive tumour progression, while protective subTME regions enriched in ECM supported tumour differentiation yet were markedly chemoprotective and translated into poor treatment response during 1st line chemotherapy. Consequently, tumours benefited from concomitant presence of both subTMEs and patients with phenotypically heterogenous stroma displayed shortened survival. Our patient-matched multidimensional data were then used to train a Random Forest model for prediction of subTME presence from bulk RNAseq samples. This again stratified PDAC patients in the independent TCGA cohort into distinct clinical outcomes by stromal phenotypic heterogeneity. In conclusion, we have delineated human PDAC stroma to subtype its heterogeneity into phenotypically distinct reactive and protective elements. This defines the active role of two overarching sub-microenvironment types in PDAC progression and sets a path towards developing novel stroma-instructed therapies.

Citation Format: Barbara T. Grünwald, Antoine Devisme, Foram Vyas, Geoffroy Andrieux, Gun Ho Jang, Kazeera Aliar, Curtis McCloskey, Andrew Macklin, Joan Miguel Romero, Laura Tamblyn, Nikolina Radulovich, Peter Bronsert, Grainne O’Kane, Julie Wilson, Jennifer Knox, Sandra Fischer, Thomas Kislinger, Melanie Boerries, Steven Gallinger, Rama Khokha. Stromal phenotypic heterogeneity fosters pancreatic cancer progression [abstract]. In: Proceedings of the AACR Virtual Special Conference on Pancreatic Cancer; 2020 Sep 29-30. Philadelphia (PA): AACR; Cancer Res 2020;80(22 Suppl):Abstract nr PR-002.

Validation of Prognostic Radiomic Features From Resectable Pancreatic Ductal Adenocarcinoma in Patients With Advanced Disease Undergoing Chemotherapy

BACKGROUND

Radiomic features in pancreatic ductal adenocarcinoma (PDAC) often lack validation in independent test sets or are limited to early or late stage disease. Given the lethal nature of PDAC it is possible that there are similarities in radiomic features of both early and advanced disease reflective of aggressive biology.

PURPOSE

To assess the performance of prognostic radiomic features previously published in patients with resectable PDAC in a test set of patients with unresectable PDAC undergoing chemotherapy.

METHODS

The pre-treatment CT of 108 patients enrolled in a prospective chemotherapy trial were used as a test cohort for 2 previously published prognostic radiomic features in resectable PDAC (Sum Entropy and Cluster Tendency with square-root filter[Sqrt]). We assessed the performance of these 2 radiomic features for the prediction of overall survival (OS) and time to progression (TTP) using Cox proportional-hazard models.

RESULTS

Sqrt Cluster Tendency was significantly associated with outcome with a hazard ratio (HR) of 1.27(for primary pancreatic tumor plus local nodes), (Confidence Interval(CI):1.01 -1.6, P-value = 0.039) for OS and a HR of 1.25(CI:1.00 -1.55, P-value = 0.047) for TTP. Sum entropy was not associated with outcomes. Sqrt Cluster Tendency remained significant in multivariate analysis.

CONCLUSION

The CT radiomic feature Sqrt Cluster Tendency, previously demonstrated to be prognostic in resectable PDAC, remained a significant prognostic factor for OS and TTP in a test set of unresectable PDAC patients. This radiomic feature warrants further investigation to understand its biologic correlates and CT applicability in PDAC patients.

Reducing dexamethasone antiemetic prophylaxis during the COVID-19 pandemic: recommendations from Ontario, Canada

Purpose

People with cancer face an elevated risk of infection and severe sequelae from COVID-19. Dexamethasone is commonly used for antiemetic prophylaxis with systemic therapy for cancer. However, dexamethasone is associated with increased risk of viral and respiratory infections, and causes lymphopenia, which is associated with worse outcomes during COVID-19 infections. Our purpose was to minimize dexamethasone exposure during antiemetic prophylaxis for systemic therapy for solid tumors during the COVID-19 pandemic, while maintaining control of nausea and emesis.

Methods

We convened an expert panel to systematically review the literature and formulate consensus recommendations.

Results

No studies considered the impact of dexamethasone-based antiemetic regimens on the risk and severity of COVID-19 infection. Expert consensus recommended modifications to the 2019 Cancer Care Ontario Antiemetic Recommendations.

Conclusion

Clinicians should prescribe the minimally effective dose of dexamethasone for antiemetic prophylaxis. Single-day dexamethasone dosing is recommended over multi-day dosing for regimens with high emetogenic risk excluding high-dose cisplatin, preferably in combination with palonosetron, netupitant, and olanzapine. For regimens with low emetogenic risk, 5-HT₃ antagonists are recommended over dexamethasone.

Nonsurgical management of advanced hepatocellular carcinoma: a clinical practice guideline

Background

Practice guidelines based on a systematic review of the literature regarding the nonsurgical management of hepatocellular carcinoma (hcc) in North America are lacking. Resection and transplantation are the foundations for cure of hcc; however, most patients are diagnosed at an advanced stage, precluding those curative treatments. A number of local or regional therapies are used and are followed by systemic therapy for advanced or progressive disease. Other treatments are available, but their efficacy, compared with those standards, is not well known.

Methods

First, systematic review questions were developed. Literature searches of the medline, embase, and Cochrane library databases (January 2000 to July 2018 or January 2005 to July 2018 depending on the question) were conducted; in addition, abstracts from the 2018 annual meeting of the American Society of Clinical Oncology were reviewed. A practice guideline was drafted that was then scrutinized by internal and external reviewers.

Results

Seventy-seven studies were included in the guideline: no guidelines, two systematic reviews, and seventy-five primary studies published in full (including one pooled analysis). Five recommendations were developed.

Conclusions

There is no evidence for or against the use of local or regional interventions other than transarterial chemoembolization for the treatment of intermediate- or advanced-stage hcc. Furthermore, there is no evidence to support the addition of sorafenib to any local or regional therapy. Sorafenib or lenvatinib are recommended for first-line systemic treatment of intermediate-stage hcc. Regorafenib or cabozantinib provide survival benefits when given as second-line treatment. Antiviral treatment is recommended in individuals with advanced hcc who are positive for the hepatitis B surface antigen.

Pembrolizumab As Second-Line Therapy in Patients With Advanced Hepatocellular Carcinoma in KEYNOTE-240: A Randomized, Double-Blind, Phase III Trial

PURPOSE

Pembrolizumab demonstrated antitumor activity and safety in the phase II KEYNOTE-224 trial in previously treated patients with advanced hepatocellular carcinoma (HCC). KEYNOTE-240 evaluated the efficacy and safety of pembrolizumab in this population.

PATIENTS AND METHODS

This randomized, double-blind, phase III study was conducted at 119 medical centers in 27 countries. Eligible patients with advanced HCC, previously treated with sorafenib, were randomly assigned at a two-to-one ratio to receive pembrolizumab plus best supportive care (BSC) or placebo plus BSC. Primary end points were overall survival (OS) and progression-free survival (PFS; one-sided significance thresholds, P = .0174 [final analysis] and P = .002 [first interim analysis], respectively). Safety was assessed in all patients who received ≥ 1 dose of study drug.

RESULTS

Between May 31, 2016, and November 23, 2017, 413 patients were randomly assigned. As of January 2, 2019, median follow-up was 13.8 months for pembrolizumab and 10.6 months for placebo. Median OS was 13.9 months (95% CI, 11.6 to 16.0 months) for pembrolizumab versus 10.6 months (95% CI, 8.3 to 13.5 months) for placebo (hazard ratio [HR], 0.781; 95% CI, 0.611 to 0.998; P = .0238). Median PFS for pembrolizumab was 3.0 months (95% CI, 2.8 to 4.1 months) versus 2.8 months (95% CI, 2.5 to 4.1 months) for placebo at the first interim analysis (HR, 0.775; 95% CI, 0.609 to 0.987; P = .0186) and 3.0 months (95% CI, 2.8 to 4.1 months) versus 2.8 months (95% CI, 1.6 to 3.0 months) at final analysis (HR, 0.718; 95% CI, 0.570 to 0.904; P = .0022). Grade 3 or higher adverse events occurred in 147 (52.7%) and 62 patients (46.3%) for pembrolizumab versus placebo; those that were treatment related occurred in 52 (18.6%) and 10 patients (7.5%), respectively. No hepatitis C or B flares were identified.

CONCLUSION

In this study, OS and PFS did not reach statistical significance per specified criteria. The results are consistent with those of KEYNOTE-224, supporting a favorable risk-to-benefit ratio for pembrolizumab in this population.

Abstract C57: Organoid profiling identifies common responders to chemotherapy in pancreatic cancer

Pancreatic cancer is the most lethal common solid malignancy. Systemic therapies are often ineffective and predictive biomarkers to guide treatment are urgently needed. We generated a pancreatic cancer patient-derived organoid (PDO) library that recapitulates the mutational spectrum and transcriptional subtypes of primary pancreatic cancer. New driver oncogenes were nominated and transcriptomic analyses revealed unique clusters. PDOs exhibited heterogeneous responses to standard-of-care chemotherapeutics and investigational agents. In a case study manner, we find that PDO therapeutic profiles paralleled patient outcomes and that PDOs enable longitudinal assessment of chemosensitivity and evaluation of synchronous metastases. We derived organoid-based gene expression signatures of chemosensitivity that predicted improved responses for many patients to chemotherapy in both the adjuvant and advanced disease settings. Finally, we nominated alternative treatment strategies for chemorefractory PDOs using targeted agent therapeutic profiling. We propose that combined molecular and therapeutic profiling of PDOs may predict clinical response and enable prospective therapeutic selection.

Citation Format: Herve Tiriac, Pascal Belleau, Dannielle Engle, Dennis Plenker, Astrid Deschenes, Tim Somerville, Fieke Froeling, Richard Moffitt, Jennifer Knox, Alexander Krasnitz, Steven Gallinger, David Tuveson. Organoid profiling identifies common responders to chemotherapy in pancreatic cancer [abstract]. In: Proceedings of the AACR Special Conference on Pancreatic Cancer: Advances in Science and Clinical Care; 2019 Sept 6-9; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2019;79(24 Suppl):Abstract nr C57.

Abstract A40: Genomic characterization of locally advanced pancreatic adenocarcinoma

Introduction: Patients with locally advanced pancreatic adenocarcinoma (LAPC) historically have a poor outcome despite having localized disease. The disease course of LAPC as compared to metastatic pancreatic adenocarcinoma (MPC) is unclear. SMAD4 mutational status has been postulated as a prognostic marker in this group. Molecular characteristics of LAPC by whole-genome sequencing (WGS) have not been reported.

Methods: Patients with treatment-naive LAPC and MPC were enrolled in the COMPASS clinical trial (NCT02750657). Clinical and demographic data were collected prospectively. Biopsy samples were enriched for tumor using laser capture microdissection. WGS and RNA sequencing (RNAseq) was performed on all patients. Tumors were evaluated for mutational status of driver genes KRAS, TP53, CDKN2A, and SMAD4 as well as modified Moffitt RNA subtypes (basal-like vs. classical).

Results: Patients with LAPC (n=27) and MPC (n=163) did not differ in terms of age, gender, smoking status, or history of diabetes. Patient with LAPC had a lower BMI (p=0.005) and lower neutrophil-lymphocyte ratio (p=0.048) than those with MPC. More patients with LAPC received FOLFIRINOX chemotherapy than those with MPC (p=0.003). Patients with LAPC had similar rates of KRAS, TP53, CDKN2A, and SMAD4 mutations, including rates of biallelic inactivation, and similar levels of tumor mutational burden to patients with MPC. There was a slight increase in the number of structural variants in MPC compared to LAPC (p=0.05). LAPC patients with SMAD4 mutations had higher baseline Ca19.9 than those with wild-type SMAD4 (p=0.0048). All patients with LAPC were modified Moffitt classical subtype on RNAseq, while 77% of patients with MPC were classical subtype (p=0.0049). LAPC patients had improved overall survival compared with MPC patients on univariate analysis (p=0.04) but not on multivariate analysis. There was no difference in survival between classical subtype LAPC and MPC patients, and no difference in survival between LAPC patients with and without SMAD4 mutations.

Conclusions: Patients with LAPC have a similar molecular profile on WGS to those with MPC with similar rates of altered drivers, in particular SMAD4. Patients with LAPC are more likely to be modified Moffitt classical subtype on RNAseq and have similar survival to those with classical subtype MPC. In our series, LAPC patients with SMAD4 mutations had similar survival to those with wild-type SMAD4.

Citation Format: Sarah L. Picardo, Grainne O'Kane, Sandra Fischer, Amy Zhang, Rob Denroche, GunHo Jang, Anna Dodd, Robert Grant, Barbara Gruenwald, Shari Moura, Yifan Wang, Elena Elimova, Rebecca Prince, George Zogopoulos, Faiyaz Notta, Julie Wilson, Steve Gallinger, Jennifer Knox. Genomic characterization of locally advanced pancreatic adenocarcinoma [abstract]. In: Proceedings of the AACR Special Conference on Pancreatic Cancer: Advances in Science and Clinical Care; 2019 Sept 6-9; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2019;79(24 Suppl):Abstract nr A40.

Pembrolizumab As Second-Line Therapy in Patients With Advanced Hepatocellular Carcinoma in KEYNOTE-240: A Randomized, Double-Blind, Phase III Trial

PURPOSE

Pembrolizumab demonstrated antitumor activity and safety in the phase II KEYNOTE-224 trial in previously treated patients with advanced hepatocellular carcinoma (HCC). KEYNOTE-240 evaluated the efficacy and safety of pembrolizumab in this population.

PATIENTS AND METHODS

This randomized, double-blind, phase III study was conducted at 119 medical centers in 27 countries. Eligible patients with advanced HCC, previously treated with sorafenib, were randomly assigned at a two-to-one ratio to receive pembrolizumab plus best supportive care (BSC) or placebo plus BSC. Primary end points were overall survival (OS) and progression-free survival (PFS; one-sided significance thresholds, P = .0174 [final analysis] and P = .002 [first interim analysis], respectively). Safety was assessed in all patients who received ≥ 1 dose of study drug.

RESULTS

Between May 31, 2016, and November 23, 2017, 413 patients were randomly assigned. As of January 2, 2019, median follow-up was 13.8 months for pembrolizumab and 10.6 months for placebo. Median OS was 13.9 months (95% CI, 11.6 to 16.0 months) for pembrolizumab versus 10.6 months (95% CI, 8.3 to 13.5 months) for placebo (hazard ratio [HR], 0.781; 95% CI, 0.611 to 0.998; P = .0238). Median PFS for pembrolizumab was 3.0 months (95% CI, 2.8 to 4.1 months) versus 2.8 months (95% CI, 2.5 to 4.1 months) for placebo at the first interim analysis (HR, 0.775; 95% CI, 0.609 to 0.987; P = .0186) and 3.0 months (95% CI, 2.8 to 4.1 months) versus 2.8 months (95% CI, 1.6 to 3.0 months) at final analysis (HR, 0.718; 95% CI, 0.570 to 0.904; P = .0022). Grade 3 or higher adverse events occurred in 147 (52.7%) and 62 patients (46.3%) for pembrolizumab versus placebo; those that were treatment related occurred in 52 (18.6%) and 10 patients (7.5%), respectively. No hepatitis C or B flares were identified.

CONCLUSION

In this study, OS and PFS did not reach statistical significance per specified criteria. The results are consistent with those of KEYNOTE-224, supporting a favorable risk-to-benefit ratio for pembrolizumab in this population.

Abstract 1500: Mediators of CD8+ cytotoxic T lymphocyte infiltration in pancreatic cancer

Pancreatic cancer continues to have the highest mortality rate of all solid cancers, with a 5-year overall survival of approximately 8%. Despite recent progress in other malignancies, immunotherapy remains ineffective against pancreatic cancer. Previous work from our group and others has shown that tumors with mismatch repair (MMR) and homologous repair (HR) deficiency have increased immune activity, likely attributable to the inherently increased mutational and neoantigen load in these patients. However, there remains a subset of pancreatic cancer patients with increased CD8+ T cell infiltration, despite lacking these specific mutational signatures. Furthermore, an increasing body of evidence has shown that mutational burden and neoantigen load only partially explain the T cell-inflamed phenotype seen in tumors, implicating the presence of additional mechanisms that drive T cell infiltration in cancer. Several recent studies have highlighted the importance of proper CD8+ T cell priming by antigen presenting cells (APCs), particularly Batf3+ dendritic cells (DCs), and subsequent tumor infiltration via chemokines for immunotherapy to be effective. In this study, we investigated the involvement of chemokines in cytotoxic T lymphocyte infiltration in pancreatic cancer. Using a bioinformatics-driven approach, we analyzed 78 treatment-naïve, primary pancreas cancer resections for associations between CD8+ tumour infiltrating lymphocytes (TILs) and chemokine expression by RNAseq. A panel of chemokines, including CCL4, CCL5, CXCL9, CXCL10, and CXCL11, was highly associated with CD8+ TILs (p &lt; 0.001). Segregating 173 tumour-enriched patient RNAseq samples based on expression of CXCL9 and CXCL10, we found those with higher expression of these chemokines had increased immune activation signatures. Importantly, this included increased MHC I presentation, presence of Batf3+ DCs, and T cell/APC co-stimulation (p &lt; 0.001), while we observed no differences in conventional predictors of CD8+ T cell infiltration such as SNV counts or neoantigens between groups. These results were consistent across ICGC and TCGA data sets. Moreover, these results were also recapitulated in 72 tumor-enriched liver metastases, suggesting an underlying immunobiology that may occur in both primary and metastatic sites. The cellular sources of these chemokines, as determined by immunohistochemical analysis, and the role of tumor-sensing innate immune pathways leading to CD8+ T cell priming, by pathway and differential gene expression analysis, are currently being investigated. Taken together, these results demonstrate a potential role for these chemokines in recruiting CD8+ T cells in pancreatic cancer. Understanding mediators driving cytotoxic T cell infiltration will help identify mechanisms leading to proper CD8+ T cell priming and homing into tumors, to stratify patients amenable for known and novel immunotherapies.

Citation Format: Joan Miguel Romero, Barbara Grünwald, Ashton Connor, Gun Ho Jang, Prashant Bavi, Aaditeya Jhaveri, Mehdi Masoomian, Sandra Fischer, Amy Zhang, Robert E. Denroche, Tracy McGaha, Faiyaz Notta, Pamela Ohashi, Grainne O'Kane, Julie Wilson, Jennifer Knox, Steven Gallinger. Mediators of CD8+ cytotoxic T lymphocyte infiltration in pancreatic cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 1500.

Risk assessment strategies for early detection and prediction of infectious disease outbreaks associated with climate change

A new generation of surveillance strategies is being developed to help detect emerging infections and to identify the increased risks of infectious disease outbreaks that are expected to occur with climate change. These surveillance strategies include event-based surveillance (EBS) systems and risk modelling. The EBS systems use open-source internet data, such as media reports, official reports, and social media (such as Twitter) to detect evidence of an emerging threat, and can be used in conjunction with conventional surveillance systems to enhance early warning of public health threats. More recently, EBS systems include artificial intelligence applications such machine learning and natural language processing to increase the speed, capacity and accuracy of filtering, classifying and analysing health-related internet data. Risk modelling uses statistical and mathematical methods to assess the severity of disease emergence and spread given factors about the host (e.g. number of reported cases), pathogen (e.g. pathogenicity) and environment (e.g. climate suitability for reservoir populations). The types of data in these models are expanding to include health-related information from open-source internet data and information on mobility patterns of humans and goods. This information is helping to identify susceptible populations and predict the pathways from which infections might spread into new areas and new countries. As a powerful addition to traditional surveillance strategies that identify what has already happened, it is anticipated that EBS systems and risk modelling will increasingly be used to inform public health actions to prevent, detect and mitigate the climate change increases in infectious diseases.

Pantoprazole Affecting Docetaxel Resistance Pathways via Autophagy (PANDORA): Phase II Trial of High Dose Pantoprazole (Autophagy Inhibitor) with Docetaxel in Metastatic Castration-Resistant Prostate Cancer (mCRPC)

BACKGROUND

Enhancing the effectiveness of docetaxel for men with metastatic castration-resistant prostate cancer (mCRPC) is an unmet clinical need. Preclinical studies demonstrated that high-dose pantoprazole can prevent or delay resistance to docetaxel via the inhibition of autophagy in several solid tumor xenografts.

MATERIALS AND METHODS

Men with chemotherapy-naive mCRPC with a prostate-specific antigen (PSA) >10 ng/mL were eligible for enrolment. Men received intravenous pantoprazole (240 mg) prior to docetaxel (75 mg/m²) every 21 days, with continuous prednisone 5 mg twice daily. Primary endpoint was a confirmed ≥50% decline of PSA. The trial used a Simon's two-stage design.

RESULTS

Between November 2012 and March 2015, 21 men with a median age of 70 years (range, 58-81) were treated (median, 6 cycles; range, 2-11). Men had received prior systemic therapies (median, 1; range, 0-3), and 14 had received abiraterone and/or enzalutamide. PSA response rate was 52% (11/21), which did not meet the prespecified criterion (≥13/21 responders) to proceed to stage 2 of the study. At interim analysis with a median follow-up of 17 months, 18 (86%) men were deceased (15 castration-resistant prostate cancer, 2 unknown, 1 radiation complication). Of the men with RECIST measurable disease, the radiographic partial response rate was 31% (4/13). The estimated median overall survival was 15.7 months (95% confidence interval [CI], 9.3-19.6) and median PFS was 5.3 months (95% CI, 2.6-12.9). There were no toxic deaths, and all adverse events were attributed to docetaxel.

CONCLUSION

The combination of docetaxel and pantoprazole was tolerable, but the resultant clinical activity was not sufficient to meet the ambitious predefined target to warrant further testing.

IMPLICATIONS FOR PRACTICE

To date, no docetaxel combination regimen has reported superior efficacy over docetaxel alone in men with metastatic castration-resistant prostate cancer (mCRPC). The PANDORA trial has demonstrated that the combination of high dose pantoprazole with docetaxel is tolerable, but the clinical activity was not sufficient to warrant further testing. The chemotherapy standard of care for men with mCRPC remains docetaxel with prednisone. Future studies of autophagy inhibitors will need to measure autophagy inhibition accurately and determine the degree of autophagy inhibition required to produce a meaningful clinical response.

Correction to: Safety and efficacy of nivolumab in combination with sunitinib or pazopanib in advanced or metastatic renal cell carcinoma: the CheckMate 016 study

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An Open-Label, Multicenter, Phase I, Dose Escalation Study with Phase II Expansion Cohort to Determine the Safety, Pharmacokinetics, and Preliminary Antitumor Activity of Intravenous TKM-080301 in Subjects with Advanced Hepatocellular Carcinoma

Lessons Learned.

TKM‐080301 showed a favorable toxicity profile at the studied dose.

TKM‐080301 targeting PLK1 through small interfering RNA mechanism did not demonstrate improved overall survival in patients with advanced hepatocellular carcinoma compared with historical control. Preliminary antitumor activity as shown in this early‐phase study does not support further evaluation as a single agent.

Background.

Polo‐like kinase 1 (PLK1) is overexpressed in hepatocellular carcinoma (HCC). Knockdown of PLK1 expression by PLK1 small interfering RNA (siRNA) in an HCC cell line showed reduced expression in RNA‐induced silencing complex and a reduction in cell proliferation.

Methods.

A 3 + 3 dose escalation plus expansion cohort at the maximum tolerated dose (MTD) was implemented. Patients with HCC, Eastern Cooperative Oncology Group (ECOG) performance status ≤2, and Child‐Pugh score A received TKM‐080301 as an intravenous infusion once every week for 3 consecutive weeks, repeated every 28 days.

Results.

The study enrolled 43 patients. The starting dose of TKM‐080301 was 0.3 mg/kg, and MTD was declared at 0.75 mg/kg. Following the development of grade 4 thrombocytopenia in two subjects on the expansion cohort, the MTD was redefined at 0.6 mg/kg. Four patients did not have any evaluable postbaseline scan. Of the other 39 subjects who had received at least 0.3 mg/kg, 18 subjects (46.2%) had stable disease (SD) by independent RECIST 1.1 criteria. By Choi criteria, eight subjects (23.1%) had a partial response (PR). For 37 assessable subjects, with 2 subjects censored, median progression‐free survival (PFS) was 2.04 months. Median survival for the whole study population was 7.5 months.

Conclusion.

TKM‐080301 was generally well tolerated. In this early‐phase study, antitumor effect for TKM 080301 was limited. Further evaluation as a single agent in large randomized trials is not warranted.

Outcomes by treatment modality in elderly patients with localized gastric and esophageal cancer

Background

We aimed to assess current treatment patterns and outcomes in elderly patients with localized gastric and esophageal (ge) cancers.

Methods

This retrospective analysis considered patients 75 years of age or older with ge cancers treated during 2012-2014. Patient demographics and tumour characteristics were collected. Overall survival (os) and disease-free survival were assessed by univariable and multivariable Cox proportional hazards regression, adjusting for demographics. Logistic regression analyses were used to examine factors affecting treatment choices.

Results

The 110 patients in the study cohort had a median age of 81 years (range: 75-99 years). Primary disease sites were esophageal (55%) and gastric (45%). Treatment received included radiation therapy alone (29%), surgery alone (26%), surgery plus perioperative therapy (14%), chemoradiation alone (10%), and supportive care alone (14%). In multivariable analyses, surgery (hazard ratio: 0.48; 95% confidence interval: 0.26 to 0.90; p = 0.02) was the only independent predictor for improved os. Patients with a good Eastern Cooperative Oncology Group performance status (p = 0.008), gastric disease site (p = 0.02), and adenocarcinoma histology (p = 0.01) were more likely to undergo surgery.

Conclusions

At our institution, few patients 75 years of age and older received multimodality therapy for localized ge cancers. Outcomes were better for patients who underwent surgery than for those who did not. To ensure optimal treatment selection, comprehensive geriatric assessment should be considered for patients 75 years of age and older with localized ge cancers.

Safety and efficacy of nivolumab in combination with sunitinib or pazopanib in advanced or metastatic renal cell carcinoma: the CheckMate 016 study

BACKGROUND

Combination treatment with immune checkpoint inhibitors and antiangiogenic drugs has shown encouraging preliminary antitumor activity across various tumor types including advanced or metastatic renal cell carcinoma (aRCC). The open-label, parallel-cohort, dose-escalation, phase I CheckMate 016 study evaluated the efficacy and safety of nivolumab in combination with antiangiogenic tyrosine kinase inhibitors or ipilimumab. Long-term outcomes from this study for the combination of nivolumab plus sunitinib or pazopanib in aRCC are presented.

METHODS

Patients with aRCC received nivolumab plus either sunitinib (50 mg/day, 4 weeks on/2 weeks off; N + S) or pazopanib (800 mg/day; N + P) until progression/unacceptable toxicity. The nivolumab starting dose was 2 mg/kg every 3 weeks, with planned escalation to 5 mg/kg every 3 weeks. Primary endpoints were safety and tolerability; antitumor activity was a secondary endpoint.

RESULTS

Arm N + S enrolled 33 patients, 19 of whom were treatment-naïve; this arm advanced to the expansion phase. Median follow-up was 50.0 months. Patients experienced high frequencies of adverse events (AEs) including treatment-related AEs (100%), grade 3/4 treatment-related AEs (82%), and treatment-related AEs leading to discontinuation (39%). Investigator-assessed objective response rate (ORR) was 55% (18/33) and median progression-free survival (PFS) was 12.7 months. Median overall survival (OS) was not reached. Arm N + P enrolled 20 patients, all had ≥1 prior systemic therapy; this arm was closed due to dose-limiting toxicities and did not proceed to expansion. Median follow-up was 27.1 months. Patients treated with N + P experienced high frequencies of AEs including treatment-related AEs (100%), grade 3/4 treatment-related AEs (70%), and treatment-related AEs leading to discontinuation (25%). Investigator-assessed ORR was 45% (9/20) and median PFS was 7.2 months. Median OS was 27.9 months.

CONCLUSIONS

The addition of standard doses of sunitinib or pazopanib to nivolumab resulted in a high incidence of high-grade toxicities limiting future development of either combination regimen. While there was no adverse impact on response and the OS outcome was notable, the findings suggest that the success of combination regimens based on immune checkpoint inhibitors and antiangiogenic drugs may be dependent on careful selection of the antiangiogenic component and dose.

TRIAL REGISTRATION

Clinicaltrials.gov identifier: NCT01472081 . Registered 16 November 2011.

Pembrolizumab in patients with advanced hepatocellular carcinoma previously treated with sorafenib (KEYNOTE-224): a non-randomised, open-label phase 2 trial

BACKGROUND

Immune checkpoint blockade therapy has shown promising results in patients with advanced hepatocellular carcinoma. We aimed to assess the efficacy and safety of pembrolizumab in this patient population.

METHODS

KEYNOTE-224 is a non-randomised, multicentre, open-label, phase 2 trial that is set in 47 medical centres and hospitals across ten countries. Eligible patients had pathologically confirmed hepatocellular carcinoma; had previously been treated with sorafenib and were either intolerant to this treatment or showed radiographic progression of their disease after treatment; an Eastern Cooperative Oncology Group performance status of 0-1; adequate organ function, and were Child-Pugh class A. Participants received 200 mg pembrolizumab intravenously every 3 weeks for about 2 years or until disease progression, unacceptable toxicity, patient withdrawal, or investigator decision. The primary endpoint was objective response, defined as the proportion of patients with complete or partial response in all patients who received at least one dose of pembrolizumab, which was radiologically confirmed by use of the Response Evaluation Criteria in Solid Tumors version 1.1 by central review. Safety was also assessed in all treated patients. This trial is ongoing but closed to enrolment and is registered with ClinicalTrials.gov number NCT02702414.

FINDINGS

Between June 7, 2016, and Feb 9, 2017, we screened 169 patients with advanced hepatocellular carcinoma, of whom 104 eligible patients were enrolled and treated. As of data cutoff on Feb 13, 2018, 17 (16%) patients were still receiving pembrolizumab. We recorded an objective response in 18 (17%; 95% CI 11-26) of 104 patients. The best overall responses were one (1%) complete and 17 (16%) partial responses; meanwhile, 46 (44%) patients had stable disease, 34 (33%) had progressive disease, and six (6%) patients who did not have a post-baseline assessment on the cutoff date were considered not to be assessable. Treatment-related adverse events occurred in 76 (73%) of 104 patients, which were serious in 16 (15%) patients. Grade 3 treatment-related events were reported in 25 (24%) of the 104 patients; the most common were increased aspartate aminotransferase concentration in seven (7%) patients, increased alanine aminotransferase concentration in four (4%) patients, and fatigue in four (4%) patients. One (1%) grade 4 treatment-related event of hyperbilirubinaemia occurred. One death associated with ulcerative oesophagitis was attributed to treatment. Immune-mediated hepatitis occurred in three (3%) patients, but there were no reported cases of viral flares.

INTERPRETATION

Pembrolizumab was effective and tolerable in patients with advanced hepatocellular carcinoma who had previously been treated with sorafenib. These results indicate that pembrolizumab might be a treatment option for these patients. This drug is undergoing further assessment in two phase 3, randomised trials as a second-line treatment in patients with hepatocellular carcinoma.

FUNDING

Merck & Co, Inc.

Organoid Profiling Identifies Common Responders to Chemotherapy in Pancreatic Cancer

Pancreatic cancer is the most lethal common solid malignancy. Systemic therapies are often ineffective, and predictive biomarkers to guide treatment are urgently needed. We generated a pancreatic cancer patient-derived organoid (PDO) library that recapitulates the mutational spectrum and transcriptional subtypes of primary pancreatic cancer. New driver oncogenes were nominated and transcriptomic analyses revealed unique clusters. PDOs exhibited heterogeneous responses to standard-of-care chemotherapeutics and investigational agents. In a case study manner, we found that PDO therapeutic profiles paralleled patient outcomes and that PDOs enabled longitudinal assessment of chemosensitivity and evaluation of synchronous metastases. We derived organoid-based gene expression signatures of chemosensitivity that predicted improved responses for many patients to chemotherapy in both the adjuvant and advanced disease settings. Finally, we nominated alternative treatment strategies for chemorefractory PDOs using targeted agent therapeutic profiling. We propose that combined molecular and therapeutic profiling of PDOs may predict clinical response and enable prospective therapeutic selection.Significance: New approaches to prioritize treatment strategies are urgently needed to improve survival and quality of life for patients with pancreatic cancer. Combined genomic, transcriptomic, and therapeutic profiling of PDOs can identify molecular and functional subtypes of pancreatic cancer, predict therapeutic responses, and facilitate precision medicine for patients with pancreatic cancer. Cancer Discov; 8(9); 1112-29. ©2018 AACR.See related commentary by Collisson, p. 1062This article is highlighted in the In This Issue feature, p. 1047.