Detection of ras Gene Mutations in Perioperative Peripheral Blood with Pancreatic Adenocarcinoma

Surgeons wish to know of any correlation between an operation and the incidence of metastasis. In perioperative periods, pancreatic cancer cells were identified by detecting mutant K‐ras gene by two‐step PCR and RFLP analysis in blood samples taken from peripheral blood. In no case was K‐ras point mutation detected in blood before operation, although the mutant band was observed in all cases at the time the lesion was resected. Surprisingly, in five of ten cases, positive bands were identified just after laparotomy, before we had reached the primary lesion. In almost all cases, mutant K‐ras was detected until the fourteenth postoperative day. These findings suggest that cancer cells exist in the circulation, and have a potential for hematogenous metastasis during the perioperative period. In conclusion, surgical stress causes hematogenous dissemination of pancreatic cancer cells, and surgeons should employ the appropriate anti‐metastasis therapy in the perioperative period.