Pancreatic cancer is a lethal malignant neoplasm, and surgical resection represents the only path to cure. Locally advanced pancreatic ductal adenocarcinoma (LAPC) has been classified as unresectable with conventional surgical techniques and has historically been classified on a continuum of metastatic disease. Combination therapy with gemcitabine and chemoradiotherapy (CRT) has rarely provided tumor downstaging and conversion to resectability. The improved efficacy of the FOLFIRINOX (fluorouracil, leucovorin, oxaliplatin, and irinotecan) regimen raised the question of its potential utility for downstaging LAPC to surgical resection.¹ Several studies have evaluated neoadjuvant FOLFIRINOX in borderline resectable and locally advanced disease, demonstrating increased surgical conversion rates.^2-6

Purpose: Detection of persistent circulating tumor DNA (ctDNA) after curative-intent surgery can identify patients with minimal residual disease (MRD) who will ultimately recur. Most ctDNA MRD assays require tumor sequencing to identify tumor-derived mutations to facilitate ctDNA detection, requiring tumor and blood. We evaluated a plasma-only ctDNA assay integrating genomic and epigenomic cancer signatures to enable tumor-uninformed MRD detection. Experimental Design: A total of 252 prospective serial plasma specimens from 103 patients with colorectal cancer undergoing curative-intent surgery were analyzed and correlated with recurrence. Results: Of 103 patients, 84 [stage I (9.5%), II (23.8%), III (47.6%), IV (19%)] had evaluable plasma drawn after completion of definitive therapy, defined as surgery only (n = 39) or completion of adjuvant therapy (n = 45). In “landmark” plasma drawn 1-month (median, 31.5 days) after definitive therapy and >1 year follow-up, 15 patients had detectable ctDNA, and all 15 recurred [positive predictive value (PPV), 100%; HR, 11.28 (P < 0.0001)]. Of 49 patients without detectable ctDNA at the landmark timepoint, 12 (24.5%) recurred. Landmark recurrence sensitivity and specificity were 55.6% and 100%. Incorporating serial longitudinal and surveillance (drawn within 4 months of recurrence) samples, sensitivity improved to 69% and 91%. Integrating epigenomic signatures increased sensitivity by 25%–36% versus genomic alterations alone. Notably, standard serum carcinoembryonic antigen levels did not predict recurrence [HR, 1.84 (P = 0.18); PPV = 53.9%]. Conclusions: Plasma-only MRD detection demonstrated favorable sensitivity and specificity for recurrence, comparable with tumor-informed approaches. Integrating analysis of epigenomic and genomic alterations enhanced sensitivity. These findings support the potential clinical utility of plasma-only ctDNA MRD detection. See related commentary by Bent and Kopetz, p. 5449

Objective: The aim of this study was to determine (1) whether preoperative factors can predict resectability of borderline resectable (BR) and locally advanced (LA) pancreatic ductal adenocarcinoma (PDAC) after neoadjuvant FOLFIRINOX, (2) which patients might benefit from adjuvant therapy, and (3) survival differences between resected BR/LA patients who received neoadjuvant FOLFIRINOX and upfront resected patients. Background: Patients with BR/LA PDAC are often treated with FOLFIRINOX to obtain a margin-negative resection, yet selection of patients for resection remains challenging. Methods: Clinicopathologic data of PDAC patients surgically explored between 04/2011-11/2016 in a single institution were retrospectively collected. Results: Following neoadjuvant FOLFIRINOX, 141 patients were surgically explored (BR: 49%, LA: 51%) and 110 (78%) were resected. Resected patients had lower preoperative CA 19-9 levels (21 vs 40 U/mL, P = 0.03) and smaller tumors on preoperative computed tomography (CT) scan (2.3 vs 3.0 cm, P = 0.03), but no predictors of resectability were identified. Median overall survival (OS) was 34.2 months from diagnosis for all FOLFIRINOX patients and 37.7 months for resected patients. Among resected patients, preoperative CA 19-9 >100 U/mL and >8 months between diagnosis and surgery predicted a shorter postoperative disease-free survival (DFS); Charlson comorbidity index >1, preoperative CA 19-9 >100 U/mL and tumor size (>3.0 cm on CT or >2.5 cm on pathology) predicted decreased OS. DFS and OS were significantly better for BR/LA PDAC patients treated with neoadjuvant FOLFIRINOX compared with upfront resected patients (DFS: 29.1 vs 13.7, P < 0.001; OS: 37.7 vs 25.1 months from diagnosis, P = 0.01). Conclusion: BR/LA PDAC patients with no progression on neoadjuvant FOLFIRINOX should be offered surgical exploration. Except size, traditional pathological parameters fail to predict survival among resected FOLFIRINOX patients. Resected FOLFIRINOX patients have survival that appears to be superior than that of resectable patients who go directly to surgery.

Review from JAMA Surgery — Perioperative Supplemental Oxygen Therapy and Surgical Site Infection — A Meta-analysis of Randomized Controlled Trials

In the past decade, the use of neoadjuvant treatment (NAT) has markedly increased for patients with borderline resectable and locally advanced pancreatic ductal adenocarcinoma (PDAC).¹ This increase has enabled a large number of patients whose tumors were considered inoperable in the past to undergo pancreatic resection,² and several studies have shown encouraging surgical outcomes,^2-4 as well as improvement in pathologic findings.^5,6