Impact of an Inter-Professional Clinic on Pancreatic Cancer Outcomes: A Retrospective Cohort Study

Background: Pancreatic ductal adenocarcinoma (PDAC) presents significant challenges in diagnosis, staging, and appropriate treatment. Furthermore, patients with PDAC often experience complex symptomatology and psychosocial implications that require multi-disciplinary and inter-professional supportive care management from health professionals. Despite these hurdles, the implementation of inter-professional clinic approaches showed promise in enhancing clinical outcomes. To assess the effectiveness of such an approach, we examined the impact of the Wallace McCain Centre for Pancreatic Cancer (WMCPC), an inter-professional clinic for patients with PDAC at the Princess Margaret Cancer Centre (PM). Methods: This retrospective cohort study included all patients diagnosed with PDAC who were seen at the PM before (July 2012-June 2014) and after (July 2014-June 2016) the establishment of the WMCPC. Standard therapies such as surgery, chemotherapy, and radiation therapy remained consistent across both time periods. The cohorts were compared in terms of survival rates, disease stage, referral patterns, time to treatment, symptoms, and the proportion of patients assessed and supported by nursing and allied health professionals. Results: A total of 993 patients were included in the review, comprising 482 patients pre-WMCPC and 511 patients post-WMCPC. In the multivariate analysis, adjusting for ECOG (Eastern Cooperative Oncology Group) and stage, it was found that post-WMCPC patients experienced longer median overall survival (mOS, HR 0.84, 95% CI 0.72-0.98, p = 0.023). Furthermore, the time from referral to initial consultation date decreased significantly from 13.4 to 8.8 days in the post-WMCPC cohort (p < 0.001), along with a reduction in the time from the first clinic appointment to biopsy (14 vs. 8 days, p = 0.022). Additionally, patient-reported well-being scores showed improvement in the post-WMCPC cohort (p = 0.02), and these patients were more frequently attended to by nursing and allied health professionals (p < 0.001). Conclusions: The implementation of an inter-professional clinic for patients diagnosed with PDAC led to improvements in overall survival, patient-reported well-being, time to initial assessment visit and pathological diagnosis, and symptom management. These findings advocate for the adoption of an inter-professional clinic model in the treatment of patients with PDAC.

Landscape of MicroRNA Regulatory Network Architecture and Functional Rerouting in Cancer

Somatic mutations are a major source of cancer development, and many driver mutations have been identified in protein coding regions. However, the function of mutations located in miRNA and their target binding sites throughout the human genome remains largely unknown. Here, we built detailed cancer-specific miRNA regulatory networks across 30 cancer types to systematically analyze the effect of mutations in miRNAs and their target sites in 3' untranslated region (3' UTR), coding sequence (CDS), and 5' UTR regions. A total of 3,518,261 mutations from 9,819 samples were mapped to miRNA-gene interactions (mGI). Mutations in miRNAs showed a mutually exclusive pattern with mutations in their target genes in almost all cancer types. A linear regression method identified 148 candidate driver mutations that can significantly perturb miRNA regulatory networks. Driver mutations in 3'UTRs played their roles by altering RNA binding energy and the expression of target genes. Finally, mutated driver gene targets in 3' UTRs were significantly downregulated in cancer and functioned as tumor suppressors during cancer progression, suggesting potential miRNA candidates with significant clinical implications. A user-friendly, open-access web portal (mGI-map) was developed to facilitate further use of this data resource. Together, these results will facilitate novel noncoding biomarker identification and therapeutic drug design targeting the miRNA regulatory networks.

SIGNIFICANCE

A detailed miRNA-gene interaction map reveals extensive miRNA-mediated gene regulatory networks with mutation-induced perturbations across multiple cancers, serving as a resource for noncoding biomarker discovery and drug development.

Primary ambulatory thromboprophylaxis in patients with pancreatic cancer receiving chemotherapy: hope or hype?

Thrombosis is the second leading cause of death in cancer patients. Patients with pancreatic cancer (PC) have a very high risk of developing venous thromboembolism (VTE). Even though primary ambulatory thromboprophylaxis (PATP) could decrease this risk, there are uncertain issues with regard to the choice and dose of anticoagulants, duration of anticoagulant therapy, and patient selection criteria. In addition, the current practice guidelines on PATP in PC patients are equivocal. This review critically appraises the evidence on the use of PATP in PC patients receiving chemotherapy.

Abstract 1298: An allosteric SHP2 inhibitor RMC-4550 induces immunogenicity in pancreatic adenocarcinoma (PDA) and enhances the cytotoxicity of CD8+ effector T cells

Background: Immunotherapy is ineffective in MSS PDA. Src homology-2 domain-containing protein tyrosine phosphatase (SHP2) mediates multiple immunosuppressive mechanisms in tumor cells and tumor microenvironment (TME). SHP2 plays an important role in oncogenic RAS signaling, the hallmark of PDA, that reduces tumor MHC-I expression and promotes immunotherapy resistance by stabilizing PD-L1. It modulates multiple T cell inhibitory pathways including PD-1 signaling via dephosphorylation of ITIM and ITSM. We hypothesize that SHP2i will increase anti-PDA immunity and help overcome resistance to PD-1 blockade when combined with gemcitabine, an active cytotoxic agent against PDA with pleiotropic immunomodulatory effects on its TME.

Methods: Mouse KPC-luc cells (derived from LSL-KrasG12D/+;LSL-Trp53R172H/+;Pdx-1-Cre GEMM) and human RAS mutant PDA cells were treated in vitro with various concentrations of RMC-4550, a potent and selective allosteric SHP2 inhibitor, to test its cytotoxicity using cell viability assay and measure tumor MHC-I and PD-L1 expression upon IFNy stimulation. Human PBMC were used for T cells in vitro experiments to examine the effect of RMC-4550 on T-cell proliferation inhibition by PD-1 ligand (PD-L1) stimulation. In vivo antitumor activity of RMC-4550 combined with αPD-1 or with αPD-1 and gemcitabine was investigated in a syngeneic KPC-luc subcutaneous model. After treatment, tumors and spleens were harvested, digested to single cell suspensions, and immune infiltrates quantified using flow cytometry.

Results: In vitro, there was no direct cytotoxicity of RMC-4550 on mouse KPC or human PDAC cells and no additive effect to gemcitabine. SHP2i increases IFNy mediated upregulation of MHC-I, and downregulates PD-L1 in both KPC mouse and MiaPaca-2 human PDA cells. In vitro, RMC-4550 reverses the PD-L1-mediated inhibition of T cell proliferation. In vivo, SHP2i with αPD-1 has a combinatorial effect on tumor growth inhibition. Gemcitabine seems to augment this effect. Preliminary data revealed no significant changes in number of immune cells in treatment groups when compared to the control group while an increase in proportion of Granzyme B+ CD8+ T cells and Ki-67+ CD8+ T cells in spleen and a decrease in proportion of PD1+ CD8+ T cells in TME was observed in RMC-4550 plus αPD-1 plus gemcitabine group compared to the control group.

Conclusion: SHP2i RMC-4550 and αPD-1 combination induces significant anti-tumor benefit in an in vivo PDA tumor model, an effect that is enhanced by adding gemcitabine. SHP2i may promote antitumor immunity in part by increasing MHC-I expression and reducing PD-L1 expression in RAS mutant PDA cells. PD-L1 mediated suppression of T cell proliferation was overcome by RMC-4550. In vivo, RMC-4550 may potentiate anti-PD-1 therapy by enhancing cytotoxicity of CD8+ effector T cells.

Citation Format: Agnieszka Looney, Uma Giri, Yezi Zhu, Alex Somma, Nisha Holay, Milad Soleimani, Heta Gandhi, Anna Capasso, Jeanne Kowalski, William Matsui, Carla Van Berg, S Gail Eckhardt, Todd Triplett, Kyaw Lwin Aung. An allosteric SHP2 inhibitor RMC-4550 induces immunogenicity in pancreatic adenocarcinoma (PDA) and enhances the cytotoxicity of CD8+ effector T cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1298.

KRAS mutation methylation clonality in early-stage pancreatic cancer

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Background: KRAS is mutated in 90% of pancreatic cancers making it a seemingly ideal target for treatment and yet, with the exception of the rare G12C mutation, KRAS is undruggable for the vast majority of pancreatic patients. Herein, we characterize, in silico, KRAS methylation-derived mutation clonal and subclonal diversity in PDAC and examine their impact upon clinical outcomes. Methods: We developed a mutation methylation (MM) clonality workflow for gene mutation assignment as clonal versus subclonal and applied it genome-wide to TCGA data. For comparison, we used the cancer cell fraction (CCF) clonality prediction. We examined clinical outcomes by comparing in months (mos), Kaplan-Meier estimated overall survival (OS) using a log-rank test and a cox model for testing several features. We performed differential gene expression, differential gene correlation, and gene set enrichment analyses (GSEA) between KRAS MM clonal versus subclonal early stage pancreatic patients. Results: Using 104 TCGA early stage pancreatic cancer patient tumors from TCGA with mutation, methylation and clinical outcomes data, we defined KRAS MM clonality (n = 70 clonal, n = 34 subclonal) and CCF clonality (n = 74 clonal, n = 28 subclonal) tumors. Clonality assignment between methods was 53% clonal and 17% subclonal concordant, and 19% discordant among samples. KRAS MM clonality was associated with significantly (p = 0.046) shorter OS (median OS = 11.5 mos) as compared to the KRAS subclonal group (median OS = 15 mos). By comparison, KRAS CCF clonal and subclonal patient groups did not differ in their OS. When RNA-Seq derived subtypes for pancreatic cancer were included in a model with our KRAS MM clonality marker, only our marker remained as significantly associated with OS. Median KRAS gene expression was significantly (p = 0.01) higher in the KRAS MM clonal versus subclonal group. A GSEA showed enrichment of MYC targets in the KRAS clonal group. We identified 72, mostly protein coding genes residing on chromosomes 5q, 7p and 8p that correlated with KRAS gene expression only in the subclonal group. Conclusions: Our analyses shows a potential clonality dissection of the established 90% KRAS mutation rate in pancreatic cancer, which based on our MM workflow, may be dissected into 61% KRAS clonal and 30% KRAS subclonal. By assigning clonality based on another DNA data type using CCF, we obtain 65% KRAS clonal and 25% KRAS subclonal. Thus, regardless of which DNA-based workflow, overall, the KRAS clonality rates are similar. There is a notable difference however in patient-level assignment of KRAS clonality as only our workflow showed poor OS associated with KRAS clonality. The introduction of a methylation-based mutation clonality marker could prove invaluable when used in combination with methylation-based circulating tumor DNA assays for patient and treatment selection, and clinical trial monitoring of tumor responses.

The Clinical Applicability of Primary Thromboprophylaxis in Ambulatory Patients With Pancreatic Cancer

ABSTRACT

Thromboembolism is a leading cause of death in ambulatory patients with cancer. Patients with pancreatic adenocarcinoma have a very high risk of developing venous thromboembolism, especially within the first 6 months of diagnosis. Although primary thromboprophylaxis could reduce this risk, there are unresolved questions concerning choice of agents for anticoagulation, duration of anticoagulation treatment, and criteria for patient selection. Furthermore, the current clinical guidelines on primary thromboprophylaxis in ambulatory patients with pancreatic cancer are ambiguous. This review seeks out to understand and critically appraise the evidence supporting the use of primary thromboprophylaxis in patients with pancreatic cancer and its clinical applicability.

Shared DNA-based copy number with divided methylation changes differentiate and clinically associate early stage pancreatic cancer tumors

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Background: There is no known molecular taxonomy of pancreatic cancer that can guide therapeutic strategies. Understanding the fundamental molecular mechanism underlying pancreatic cancer biology remains an unmet need. We explore the extent to which combinations of DNA-based molecular changes in copy number (CN) and methylation separate early stage PAAD tumors and associated with survival outcomes. Methods: We performed genome-wide combined cluster analyses on DNA-based CN and methylation changes using TCGA data. We examined cluster associations with clinical outcomes by comparing in months (mos), Kaplan--Meier estimated overall survival (OS) and disease-free interval (DFI) using a log-rank test. We performed additional comparisons among CN-Methylation derived clusters with respect to PAAD phenotypes. Results: Using 78 early stage pancreatic cancer tumors from TCGA with CN, methylation and clinical outcomes data, we identified two patient clusters with distinct gene copy number signatures that when combined with three methylation signatures, resulted in three additional clusters. Thus, the same gene CN signature, when combined with different methylation signatures, further differentiated tumors into sub-clusters with varying levels of associations with clinical outcome. Among them, analogous to current gene-expression based subtypes, we also identified an immune-rich subtype that was associated with improved overall survival (n=21, median OS=16mos; DFI=16mos), and an extracellular matrix (ECM)-rich with worse survival (n=19, median OS=12mos; DFI=8mos). Unlike previous expression subtypes, we identified another metabolic-enriched subtype with the same worse median OS and DFI, differentiated by methylation with the ECM-rich subtype. The improved OS cluster had a signature of CN neutral and increased methylation, while the poor cluster had a signature of CN gains and increased methylation among a set of genes distinct from the improved cluster. No significant differences in age, site, microsatellite instability and KRAS status among clusters were noted. Notably, in a multivariable model that included gene expression-based subtypes, only our DNA-level subtypes remained significantly associated with overall survival. Conclusions: While RNA-level changes often display large variations, DNA-level changes are more robust. Copy number changes appear to separate tumors into poor and improved prognosis clusters, while methylation appears to inform on the further separation of poor prognosis into various levels. A DNA-based molecular taxonomy for early stage pancreatic cancer could prove invaluable when used in combination with methylation-based circulating tumor DNA assays for clinical trial monitoring of tumor responses.

Systematic review and REMARK scoring of renal cell carcinoma (RCC) prognostic circulating biomarker manuscripts

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Background: No validated biomarkers exist to help guide prognosis of RCC patients. This study seeks to determine the current state of published prognostic RCC biomarker manuscripts and evaluate their quality using the REMARK criteria. Methods: The phrase “(renal cell carcinoma OR renal cancer OR kidney cancer OR kidney carcinoma) AND circulating AND (biomarkers OR cell free DNA OR tumor DNA OR methylated cell free DNA OR methylated tumor DNA)” was searched in Embase, Medline and PubMed during March 2018. One author (MI) selected all relevant manuscripts from the search results, and two authors (MI and SP) independently scored all relevant manuscripts using the REMARK guidelines (maximum 20 points comprised of 20 items subdivided into 48 criteria). Results: The search identified 525 publications: 73 were valid, 436 were rejected, and 26 were uncertain of their relevance. Amongst the valid publications, 33 were manuscripts of primary research (remainder: 26 review papers, 14 abstracts): manuscripts evaluating ≥ 2 biomarkers (n = 8) and novel biomarkers not published elsewhere (n = 7) comprised the majority. The median REMARK score was 10.6 (range 6.4-14.2). All manuscripts stated their marker, study objectives and method of case selection. The lowest scoring criteria were lack of: description of time between storage of blood/serum and marker assay (n = 2); flow or study profile diagram (n = 2); blinding of the person making the marker assessment to clinical outcomes (n = 3); and pre-specified hypotheses (n = 3). In total, only 8 studies reported a hazard or odds ratio. Using Pearson’s correlation, there was no association with either year of publication (median 2014; range 2004-2018; r2 = 0.14; p = 0.44) or impact factor (median 5.168; range 1.2-26.303; r2 = 0.24; p = 0.17) with REMARK score. Conclusions: Despite several published manuscripts on RCC prognostic biomarkers, most poorly adhere to the REMARK guidelines; this may be the cause for the paucity of a validated RCC biomarker to help supplement or supplant current clinical prognostic criteria. Better designed studies and appropriate reporting of methods, results and interpretation are required to address this urgent unmet need.

Impact of an inter-professional clinic on pancreatic cancer outcomes: The Princess Margaret Cancer Centre (PM) experience

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Background: Patients with pancreatic ductal adenocarcinoma (PDAC) have limited treatment options. Management of complex symptoms and psychosocial implications requires an interprofessional approach as prognosis is often measured in months. A multidisciplinary approach has been associated with improvement in clinical outcomes including survival. We aimed to evaluate the impact of an inter-professional approach for PDAC patients at the Wallace McCain Centre for Pancreatic Cancer (WMCPC) at PM on their management and clinical outcomes. Methods: We undertook retrospective review of all patients with PDAC seen at PM two years before (July ‘12 – June ‘14) and two years after (July ‘14 – June ‘16) establishment of the WMCPC. Standard therapies (surgical approach, chemotherapy, radiation therapy) were the same during both time periods. Comparison of overall survival (OS), stage at diagnosis, surgical outcomes, waiting times, and proportion seen by social worker, dietician and clinical nurse specialist (CNS) was explored with descriptive statistic and survival analysis. Results: A total of 993 patients were reviewed; 482 patients pre- and 511 patients post-WMCPC. Age (median 67 yrs), sex (54% men) and stage III/IV (52%) were similar in both groups. There was a trend to improved OS in the post-WMCPC group (9.6 vs. 10.9 m; p = 0.055); multivariable analysis found a significant improvement in OS after adjustment for performance status and stage (p = 0.023; HR 0.84, 95% CI 0.72-0.98). Rate of R0 versus R1/R2 resection for curative surgery (n = 264, 28%) was similar in both groups. Time from referral to first clinic visit significantly decreased from 13.4 to 8.8 days in the post-WMCPC group (p < 0.001) as did time from first clinic appointment to diagnostic biopsy (25.9 vs. 16.9 days, p = 0.022). Patients in the post-WMCPC were more frequently seen by a social worker, dietician or CNS (8% vs. 38%, 9% vs. 35% and 31% vs. 50% respectively, p < 0.001). Conclusions: Establishment of an interprofessional clinic for the treatment of PDAC patients at PM has streamlined diagnosis, aided symptom management and improved overall survival. This has implications for planning care delivery models and proves the value of this intervention.

A phase II trial of GSK2256098 and trametinib in patients with advanced pancreatic ductal adenocarcinoma (PDAC) (MOBILITY-002 Trial, NCT02428270)

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Background: MEK (mitogen-activated protein kinase kinase) is activated through mutated KRAS in > 90% of PDAC. Focal adhesion kinase (FAK) integrates signals from integrins and growth factor receptors. MEK and FAK are frequently co-activated in PDAC providing a rationale for dual inhibition with GSK2256098, an oral FAK inhibitor, and trametinib, an oral allosteric MEK1/2 inhibitor. Methods: Patients with advanced PDAC patients who progressed after first line chemotherapy were treated with GSK2256098 250mg twice daily and trametinib 0.5mg once daily in 28 day cycles. The primary endpoint was antitumor activity measured by clinical benefit (CB; complete response, partial response, or stable disease ≥24 weeks) by RECIST 1.1. We planned to enrol 24 patients using a 2-stage minimax design (p0 = 0.15, p1 = 0.40; alpha = 0.05, power 0.86). The combination would be considered active if > 7/24 response-evaluable patients achieved CB; and inactive if 2/12 or fewer patients achieved CB at the end of stage 1. Response assessment was performed every 2 cycles. Results: Between June/16 and June/17, 16 patients were enrolled. Five were not evaluable for response. Of 11 evaluable patients, 10 had PD as best tumor response and one had SD for 4 months. One response unevaluable patient who had rapidly progressed on 1st line FOLFIRINOX chemotherapy with a basal-like tumor by RNA-sequencing and KRAS amplification achieved clinical stability for 5 months with a > 50% decline in serum CA19-9 after 3 months of treatment and symptomatic improvement. No treatment related Grade≥3 adverse events (AEs) were observed. The most common treatment related grade 2 AEs were acneiform rash (19%), diarrhea (13%), nausea (6%), fatigue (6%), proteinuria (6%), paronychia (6%), and retinal detachment (6%). The median progression free survival was 1.6 (95% CI 1.5-1.8) months and the median overall survival was 3.6 (95% CI 2.7-not reached) months. Conclusions: GSK2256098 and trametinib was well tolerated but was not active in unselected advanced PDAC. Correlative studies are ongoing to evaluate RNA-expression subtypes and dynamic markers of pathway inhibition from serial tumor biopsies and cell free DNA. Clinical trial information: NCT02428270.

Genomics-driven precision medicine for advanced pancreatic ductal carcinoma (PDAC): Early results from the COMPASS trial (NCT02750657)

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Background: COMPASS is a prospective study with the primary aim to identify predictive mutational and transcriptional features in advanced PDAC for improved patient stratification and treatment selection. Methods: Patients with advanced PDAC were prospectively recruited prior to first-line combination chemotherapy for whole genome sequencing (WGS) and RNA sequencing (RNASeq). Fresh tumor tissue was acquired by image guided percutaneous core needle biopsy of locally advanced primary or metastatic tumors. Laser capture microdissection was performed for all cases to ensure high-resolution genomic analyses. Primary endpoint was feasibility to report WGS results prior to first disease assessment CT scan at 8 weeks. The main secondary endpoint was discovery of patient subsets with predictive mutational and transcriptional signatures. Results: Of 63 patients who underwent a tumor biopsy between December 2015 and June 2017, WGS and RNASeq were successful in 62 (98%) and 60 (95%), respectively. Genomic results were reported at a median of 35 days (range 19-52 days) from biopsy, meeting the primary feasibility endpoint. Three patients with an ‘unstable’ genomic subtype, including two with a novel ‘duplicator’ phenotype, responded well to m-FOLFIRINOX. Of two cases with the same germline BRCA2 mutation, only the chemotherapy responder had loss of heterozygosity and genomic hallmarks of double stranded break repair deficiency. Approximately 25% of tumors displayed the basal-like RNA expression signature and these were chemotherapy resistant, with tumor shrinkage mainly observed in those with the classical RNA subtype (P = 0.003). Thirty percent of patients had potentially actionable genetic alterations. Conclusions: Prospective comprehensive genomic profiling of advanced PDAC is feasible and our early data indicate that chemotherapy response differs among patients with different genomic/transcriptomic subtypes providing the impetus for further studies. Clinical trial information: NCT02750657.

The impact of lung and bone metastases on prognosis in advanced PDAC

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Background: Pancreatic ductal adenocarcinoma (PDAC) remains a highly fatal disease inherently resistant to cytotoxic treatment. Despite the prevalence of liver and peritoneal metastases, subsets of patients also develop lung and bone metastases highlighting phenotypic heterogeneity. We reviewed the prognostic implications of metastatic sites on survival. Methods: This retrospective cohort study included all patients with PDAC who received surgical or oncological treatment at the University Health Network from September 2012 until December 2016. Clinical and pathological variables were obtained from patient electronic records. Radiological images and pathology reports were reviewed to ascertain sites of metastatic disease. The Kaplan-Meier method for survival and multivariable cox regression analysis identified prognostic factors. Results: 1153 patients were reviewed and 985 were included. 55% were male and the median age at diagnosis was 67 years. 287 (29%) completed curative surgery and 698 (71%) had locally advanced or metastatic disease; the median survival was 22 months and 9 months respectively. Lung and bone metastases were present in 18% (N = 180) and 6% (N = 58) of patients. In multivariable analysis increasing age and stage at diagnosis correlated with inferior survival (p < 0.0001) and the presence of any lung (HR 0.77; 95% CI 0.63-0.94, p = 0.01) or bone metastases (HR 0.74; 95% CI 0.54-1.0, p = 0.05) resulted in improved outcomes. Liver and peritoneal disease were not prognostic. Sex and family history of PDAC did not associate with survival. There was no association between site of metastases and sex however patients with bone metastases were significantly younger at first diagnosis (median age 63yrs, p < 0.01). Conclusions: Patients with advanced PDAC and metastases to lung or bone may represent distinct biological subtypes of PDAC. Molecular profiling of available tissue is ongoing.

Prospective genomic/transcriptomic profiling of advanced pancreatic ductal adenocarcinoma (PDAC) for personalized therapy: Feasibility and preliminary results from the COMPASS study (NCT02750657)

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Background: Prospective characterization of advanced PDAC using whole genome sequencing (WGS) and whole transcriptome sequencing (WTS) may identify patients (pts) who will benefit from a personalized treatment strategy. The feasibility of this approach has not previously been established in PDAC. Methods: Advanced PDAC pts with ECOG PS 0-1 and accessible metastatic or primary tumors, were recruited. A fresh tumor sample for WGS and WTS was obtained by percutaneous biopsy and a reference whole blood sample for germline DNA analysis collected before starting 1st line palliative chemotherapy. Tumor biospecimens were enriched by laser capture microdissection before genomic analysis. The primary endpoint was feasibility (to report WGS results within 56 days in 40 of the first 50 recruited pts.) with a plan to accrue 200 pts. Results: From Dec 2015 – Jan 2017, 42 pts with advanced PDAC safely underwent tumor biopsy (32 liver, 1 omentum, 1 adrenal, 8 primary tumor). Adequate tumor biospecimens were obtained in all but one pt. The median number of tissue cores was 5 (range 3-6). The median post-enrichment tumor cellularity was 77% (range 37-93). WGS was successful for all samples analyzed. In 41 of 42 pts (97.6%), WGS was feasible and results were reported within 56 days (Median 37 days; range 19 to 52 days) meeting the primary endpoint. Potentially actionable somatic genetic aberrations were found in 12 pts (29%) involving ARID1A (N = 4), PIK3CA (N = 1), PDGFRB (N = 1), ERBB4 (N = 1), ATM (N = 2), CDK4 (N = 1) and CDK6 (N = 2). One pt with a germline BRCA2 mutation and another with somatic DSBR mutation signature achieved partial response with FOLFIRINOX (FFX). WTS results were available for 35 pts (85%). Of those, 19 were evaluable for FFX response. Eight of 9 pts (88%) with ‘classic’ signature and 4 of 10 pts (40%) with ‘basal like’ signature had tumor shrinkage with FFX (P = 0.08). Conclusions: Prospective comprehensive genomic profiling of advanced PDAC is feasible with an acceptable turnaround time. Approximately 30% of advanced PDAC pts have targetable genomic signatures and aberrations. RNA signature may predict FFX response.

Overall survival (OS) achieved with gemcitabine (G) or gemcitabine-abraxane (GA) in patients (pts) with advanced pancreatic ductal adenocarcinoma (PDAC) who received first line modified FOLFIRINOX (m-FFX) palliative chemotherapy

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Background: The standard second line treatment in advanced PDAC pts after m-FFX first line palliative chemotherapy is not clearly defined. G is the standard 2nd line treatment in Canada and GA can only be prescribed for pts with a private fund or private drug plan that covers the cost of Abraxane. More data is needed to establish OS achieved with 2ndline G or GA. Methods: The OS of PDAC pts treated with G or GA after m-FFX palliative chemotherapy given between 01-Dec-2011 and 30-Nov-2015 at the Princess Margaret Cancer Centre (PM), Toronto, Canada were retrospectively reviewed. OS was calculated from date of commencement of 2ndline treatment until death or date of last oncology follow up. Results: Over the 4-year study period, 132 pts were treated with 1st line palliative m-FFX at PM. Of them, at disease progression, 78 (59%) pts received a 2ndline therapy (50 G, 17 GA, 9 clinical trials, and 2 other). The results including demographics, treatment details and survival outcomes of patients treated with G and GA are summarized in the Table 1. Conclusions: Our results do not support single agent G after m-FFX 1st line palliative chemotherapy as median duration of treatment was too short and OS observed with G in this setting is very much limited. The median duration of treatment on GA and OS achieved with GA seem superior but sample size was too small to make a conclusion. [Table: see text]

Preliminary results of a phase I/IIa study of BMS-986156 (glucocorticoid-induced tumor necrosis factor receptor–related gene [GITR] agonist), alone and in combination with nivolumab in pts with advanced solid tumors

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Background: BMS-986156 is a fully human IgG1 agonist mAb that binds GITR and promotes T effector cell activation and possible reduction/inactivation of T regulatory cells. Preclinical data show enhanced antitumor T-cell activity with anti-GITR + anti–programmed death-1 (PD-1). Here we describe preliminary dose escalation data from a phase I/IIa study of BMS-986156 ± nivolumab (anti–PD-1 mAb) in pts with advanced solid tumors (NCT02598960). Methods: During dose escalation, pts received BMS-986156 (10–800 mg) or BMS-986156 (30–800 mg) + nivolumab (240 mg) every 2 weeks. Objectives included safety (primary), immunogenicity, pharmacokinetics (PK), pharmacodynamics (PD), and efficacy. Results: As of Dec 12, 2016, 66 pts were treated with BMS-986156 (n = 29) or BMS-986156 + nivolumab (n = 37).No dose-limiting toxicities (DLTs) were reported during dose escalation. The most common treatment-related adverse events reported with BMS-986156/BMS-986156 + nivolumab included pyrexia (21%/30%), chills (10%/16%), and fatigue (14%/14%); events were G1/2 in all pts except for 4 pts (6%) treated with the combination (G3 lipase [n = 1], G3 lung infection [n = 1], G3 fatigue [n = 1], and G3 aspartate aminotransferase with G4 creatine phosphokinase [n = 1; leading to discontinuation of treatment]). Preliminary data indicate that the incidence of immunogenicity to BMS-986156 was low when BMS-986156 ± nivolumab was administered. Preliminary data also indicate that BMS-986156 ± nivolumab exhibits linear PK with dose proportionality after a single dose, and BMS-986156 ± nivolumab is biologically active in PD analyses in peripheral blood. Initial antitumor activity has been observed in several pts treated with the combination; these data will be reported. Conclusions: This is the first report of clinical data with an anti-GITR mAb ± a PD-1 inhibitor.BMS-986156 ± nivolumab was well tolerated, with no DLTs and low immunogenicity. Antitumor activity was observed with BMS-986156 + nivolumab at doses predicted to be biologically active. Further evaluation of this combination in pts with advanced solid tumors is ongoing. Clinical trial information: NCT02598960.