Technique of Circumferential Divestment of the Superior Mesenteric Artery for Locally Advanced Pancreatic Cancer.

Abstract

Background: Locally advanced pancreatic cancer (LAPC) that involves more than 180° of contact with the superior mesenteric artery (SMA) is defined as unresectable. With advances in multimodal therapies, some cases with a favorable response to induction treatment have become candidates for resection.¹ Although divestment of the SMA is now widely adopted,^2,3 a standardized surgical technique for resecting tumors that encircle the SMA has yet to be established.

Patients and methods: Three patients with LAPC received a median of 8 months of chemotherapy and a total radiation dose of 50.4 gray (Gy) in 28 fractions (preoperative chemoradiotherapy, CRT) with oral S-1, followed by conversion pancreaticoduodenectomy with SMA divestment. The chemotherapy regimen and timing of radiation therapy varied by case: the first case received gemcitabine monotherapy after CRT, the second case received CRT after gemcitabine plus nab-paclitaxel (GnP), and the third case received CRT after GnP, followed by a switch to modified fluorouracil, irinotecan, and oxaliplatin (mFOLFIRINOX) before surgery.

Results: All patients satisfied the ABCD criteria, which included (A) tumor shrinkage, (B) normalization of cancer antigen (CA)19-9 levels, (C) a modified Glasgow Prognostic Score of 0, and (D) a minimum of 6 months of chemotherapy.⁴ Each patient underwent circumferential SMA adventitia divestment and portal vein resection. Postoperative courses were favorable, with a median hospital stay of 17 days, although one patient required readmission owing to delayed pancreatic fistula. The resection margins were measured at 0.9 mm, 1.4 mm, and 4.0 mm, respectively.

Conclusions: Circumferential divestment of the SMA for LAPC can be safely performed following chemoradiotherapy, yielding favorable short-term outcomes.