Patient-derived Organoid Pharmacotyping is a Clinically Tractable Strategy for Precision Medicine in Pancreatic Cancer

Objective: PDAC patients who undergo surgical resection and receive effective chemotherapy have the best chance of long-term survival. Unfortunately, we lack predictive biomarkers to guide optimal systemic treatment. Ex-vivo generation of PDO for pharmacotyping may serve as predictive biomarkers in PDAC. The goal of the current study was to demonstrate the clinical feasibility of a PDO-guided precision medicine framework of care. Methods: PDO cultures were established from surgical specimens and endoscopic biopsies, expanded in Matrigel, and used for high-throughput drug testing (pharmacotyping). Efficacy of standard-of-care chemotherapeutics was assessed by measuring cell viability after drug exposure. Results: A framework for rapid pharmacotyping of PDOs was established across a multi-institutional consortium of academic medical centers. Specimens obtained remotely and shipped to a central biorepository maintain viability and allowed generation of PDOs with 77% success. Early cultures maintain the clonal heterogeneity seen in PDAC with similar phenotypes (cystic-solid). Late cultures exhibit a dominant clone with a pharmacotyping profile similar to early passages. The biomass required for accurate pharmacotyping can be minimized by leveraging a high-throughput technology. Twenty-nine cultures were pharmacotyped to derive a population distribution of chemotherapeutic sensitivity at our center. Pharmacotyping rapidly-expanded PDOs was completed in a median of 48 (range 18-102) days. Conclusions: Rapid development of PDOs from patients undergoing surgery for PDAC is eminently feasible within the perioperative recovery period, enabling the potential for pharmacotyping to guide postoperative adjuvant chemotherapeutic selection. Studies validating PDOs as a promising predictive biomarker are ongoing.Peer reviewe

Neoadjuvant chemotherapy is associated with improved outcomes in patients with stage 1A and 1B pancreatic cancer undergoing surgery: An NCDB study

Background: The use of neoadjuvant chemotherapy (NAC) for pancreatic ductal adenocarcinoma (PDAC) has shown clear advantages in locally advanced and borderline resectable disease. The benefit in upfront resectable PDAC is debated. Moreover, in early clinical stages IA/IB, potential benefits including improved R0 resection rate, decreased tumor upstaging, and survival, are not clear. We hypothesize that NAC will be associated with improved outcomes and survival compared to adjuvant therapy in patients with clinical stage IA/IB PDAC. Methods: The National Cancer Database (NCDB) PUFs (2004-2017) were used to perform a retrospective review of patients with clinical stage IA or IB PDAC undergoing surgery. Treatment groups were selected based on timing of chemotherapy. Patients receiving chemotherapy or surgery alone were excluded. Results: We identified 6,613 patients with clinical stage IA or IB PDAC who underwent surgery. The neoadjuvant therapy group (NAT) included 1,533 patients who received neoadjuvant or perioperative chemotherapy, and the adjuvant therapy group (AT) contained 5080 patients who received chemotherapy after surgery. Patients in the NAT had higher rates of T1 and T2 disease and lower rates of T3 pathology compared to the AT (pT1: 18.7% vs 7.8%; pT2: 20.1 vs 18.6%; pT3: 59.3% vs 72.1%, pConclusions: NAC is beneficial in patients with stage IA/IB PDAC undergoing surgical resection as it is associated with improved oncologic outcomes including increased R0 resection rate, decreased tumor upstaging, lymph node metastasis, and LVI. Furthermore, patients receiving NAC were found to have improved survival over those getting adjuvant therapy. Based on these results, we recommend all patients diagnosed with PDAC be considered for NAC prior to surgery

A phase 2 study of GVAX colon vaccine with cyclophosphamide and pembrolizumab in patients with mismatch repair proficient advanced colorectal cancer.

BACKGROUND: Mismatch repair proficient (MMRp) colorectal cancer (CRC) has been refractory to single-agent programmed cell death protein 1 (PD1) inhibitor therapy. Colon GVAX is an allogeneic, whole-cell, granulocyte-macrophage colony-stimulating factor -secreting cellular immunotherapy that induces T-cell immunity against tumor-associated antigens and has previously been studied in combination with low-dose cyclophosphamide (Cy) to inhibit regulatory T cells. METHODS: We conducted a single-arm study of GVAX/Cy in combination with the PD1 inhibitor pembrolizumab in patients with advanced MMRp CRC. Patients received pembrolizumab plus Cy on day 1, GVAX on day 2, of a 21-day cycle. The primary endpoint was the objective response rate by Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1. Secondary objectives included safety, overall survival, progression-free survival, changes in carcinoembryonic antigen (CEA) levels, and immune-related correlates. RESULTS: Seventeen patients were enrolled. There were no objective responses, and the disease control rate was 18% by RECIST 1.1. The median progression-free survival was 82 days (95% confidence interval [CI], 48-97 days) and the median overall survival was 213 days (95% CI 179-441 days). Biochemical responses (≥30% decline in CEA) were observed in 7/17 (41%) of patients. Grade ≥ 3 treatment-related adverse events were observed in two patients (hemolytic anemia and corneal transplant rejection). Paired pre- and on-treatment biopsy specimens showed increases in programmed death-ligand 1 expression and tumor necrosis in a subset of patients. CONCLUSIONS: GVAX/Cy plus pembrolizumab failed to meet its primary objective in MMRp CRC. Biochemical responses were observed in a subset of patients and have not previously been observed with pembrolizumab monotherapy in MMRp CRC, indicating that GVAX may modulate the antitumor immune response