KRAS mutation detection by liquid biopsy for pancreatic ductal adenocarcinoma

The clinical utility of liquid biopsy (LB) for pancreatic ductal adenocarcinoma (PDAC) remain understudied. Our single-institution cohort of 311 PDAC patients with non-tumor tissues informed LB found 81.2% positivity (N = 186) in metastatic cases and in 52.4% (N = 43) of localized disease. KRAS mutations were detected in 64.6% (N = 148) of metastatic cases and 16% (N = 13) for localized disease. Positive LB, especially KRAS mutation detection, is associated with worse overall survival (OS) in metastatic PDAC (median 14.5 vs. 31.3 months, HR = 2.7, 95%CI = 1.7-4.3, P < 0.0001). The positive concordance rates of KRAS and TP53 mutations were 63% and 68% in metastatic disease but only 7% (KRAS) and 33% (TP53) in localized disease, respectively. Among the 41 patients who underwent serial liquid biopsy testing, 25% tested positive after an initial negative result. LB detects therapeutically targetable mutations in 58.5% of PDAC patients and is associated with OS.