Sung Joo Kim, Mi-Ju Kim1, Ji-Soo Han2, You-Na Sung, Soyeon An3, Jae Hoon Lee4, Ki Byung Song4, Dae Wook Hwang4, Sang Soo Lee5, HyungJun Cho2, Song Cheol Kim4, James R Eshleman6, Seung-Mo Hong. 1. Asan Institute for Life Sciences, Asan Medical Center. 2. Department of Statistics, Korea University, Seoul. 3. Department of Pathology, Incheon St Mary's Hospital, College of Medicine, The Catholic University of Korea, Incheon. 4. Departments of Surgery and. 5. Gastroenterology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea. 6. Department of Pathology, Sol Goldman Pancreatic Cancer Research Center, Johns Hopkins Medical Institutions, Baltimore, MD.
Abstract
OBJECTIVE: Although complete surgical resection is the only curative method for pancreatic cancer, the radial resection margins of pylorus-preserving pancreaticoduodenectomy specimens might be underevaluated. METHODS: KRAS mutation was assessed with droplet digital polymerase chain reaction on cells collected from the radial resection margins of 81 patients, and the results were compared with those of conventional pathologic resection margin (pRM) evaluation. RESULTS: KRAS mutation was detected in 76 patients (94%), and molecular resection margin (mRM) positivity defined by a KRAS mutation rate of 4.19% or greater was observed in 18 patients (22%). Patients with mRM-positive had significantly worse recurrence-free survival (RFS) than those with mRM-negative in entire groups (P = 0.008) and in subgroups without chemotherapy or radiation therapy (all, P < 0.001). When combined pRMs-mRMs were evaluated, patients with combined pRM-mRM-positive (either pRM- or mRM-positive) had significantly worse RFS than those with combined resection margin-negative (both pRM and mRM negative) by univariate (P = 0.002) and multivariate (P = 0.03) analyses. CONCLUSIONS: KRAS mutational analysis with ultrasensitive droplet digital polymerase chain reaction of the radial resection margin in pancreatic cancer patients who underwent pylorus-preserving pancreaticoduodenectomy can provide more accurate information on RFS by using alone or in combination with conventional pRM evaluation, especially in patients without chemotherapy or radiation therapy.
OBJECTIVE: Although complete surgical resection is the only curative method for pancreatic cancer, the radial resection margins of pylorus-preserving pancreaticoduodenectomy specimens might be underevaluated. METHODS:KRAS mutation was assessed with droplet digital polymerase chain reaction on cells collected from the radial resection margins of 81 patients, and the results were compared with those of conventional pathologic resection margin (pRM) evaluation. RESULTS:KRAS mutation was detected in 76 patients (94%), and molecular resection margin (mRM) positivity defined by a KRAS mutation rate of 4.19% or greater was observed in 18 patients (22%). Patients with mRM-positive had significantly worse recurrence-free survival (RFS) than those with mRM-negative in entire groups (P = 0.008) and in subgroups without chemotherapy or radiation therapy (all, P < 0.001). When combined pRMs-mRMs were evaluated, patients with combined pRM-mRM-positive (either pRM- or mRM-positive) had significantly worse RFS than those with combined resection margin-negative (both pRM and mRM negative) by univariate (P = 0.002) and multivariate (P = 0.03) analyses. CONCLUSIONS:KRAS mutational analysis with ultrasensitive droplet digital polymerase chain reaction of the radial resection margin in pancreatic cancerpatients who underwent pylorus-preserving pancreaticoduodenectomy can provide more accurate information on RFS by using alone or in combination with conventional pRM evaluation, especially in patients without chemotherapy or radiation therapy.