Feasibility of pancreatectomy following high-dose proton therapy for unresectable pancreatic cancer

AIM: To review surgical outcomes for patients undergoing pancreatectomy after proton therapy with concomitant capecitabine for initially unresectable pancreatic adenocarcinoma. METHODS: From April 2010 to September 2013, 15 patients with initially unresectable pancreatic cancer were treated with proton therapy with concomitant capecitabine at 1000 mg orally twice daily. All patients received 59.40 Gy (RBE) to the gross disease and 1 patient received 50.40 Gy (RBE) to high-risk nodal targets. There were no treatment interruptions and no chemotherapy dose reductions. Six patients achieved a radiographic response sufficient to justify surgical exploration, of whom 1 was identified as having intraperitoneal dissemination at the time of surgery and the planned pancreatectomy was aborted. Five patients underwent resection. Procedures included: Laparoscopic standard pancreaticoduodenectomy (n = 3), open pyloris-sparing pancreaticoduodenectomy (n = 1), and open distal pancreatectomy with irreversible electroporation (IRE) of a pancreatic head mass (n = 1). RESULTS: The median patient age was 60 years (range, 51-67). The median duration of surgery was 419 min (range, 290-484), with a median estimated blood loss of 850 cm(3) (range, 300-2000), median ICU stay of 1 d (range, 0-2), and median hospital stay of 10 d (range, 5-14). Three patients were re-admitted to a hospital within 30 d after discharge for wound infection (n = 1), delayed gastric emptying (n = 1), and ischemic gastritis (n = 1). Two patients underwent R0 resections and demonstrated minimal residual disease in the final pathology specimen. One patient, after negative pancreatic head biopsies, underwent IRE followed by distal pancreatectomy with no tumor seen in the specimen. Two patients underwent R2 resections. Only 1 patient demonstrated ultimate local progression at the primary site. Median survival for the 5 resected patients was 24 mo (range, 10-30). CONCLUSION: Pancreatic resection for patients with initially unresectable cancers is feasible after high-dose [59.4 Gy (RBE)] proton radiotherapy with a high rate of local control, acceptable surgical morbidity, and a median survival of 24 mo.