Comparison of Radical Antegrade Modular Pancreatosplenectomy Versus Standard Distal Pancreatectomy for Pancreatic Ductal Adenocarcinoma: A Propensity Score Matching Study.

Abstract

Radical antegrade modular pancreatosplenectomy (RAMPS) is a modified procedure with better margin resection and more lymph node harvest compared to standard distal pancreatectomy (SDP) in the treatment of pancreatic ductal adenocarcinoma (PDAC). The role of RAMPS regarding long-term survival has not been clearly defined owing to a lack of randomized controlled trials. The aim of this study was to compare long-term survival after RAMPS and SDP for patients with PDAC. This single-center retrospective cohort study was conducted from November 2013 to December 2022. Consecutive patients with PDAC who underwent RAMPS and SDP were reviewed. Patients with the following characteristics were excluded: distant metastasis, tumor recurrence, and second primary malignancy. Propensity score matching (PSM) was used to balance differences in baseline patient characteristics between RAMPS and SDP groups. The primary outcome was the association between surgery type and overall survival (OS) assessed using Cox proportional hazards regression models. A total of 581 patients with PDAC (336 [57.8%] men, mean [SD] age, 64.8 [9.3] years) were analyzed. RAMPS (197 [33.9%]) was correlated with the higher frequencies of borderline resectable pancreatic cancer (68 [34.5%]), arterial resection (37 [18.8%]), T4 stage tumor (80 [40.6%]), nodal metastasis (117 [59.4%]), negative posterior margin (153 [77.7%]), and a greater number of lymph nodes harvested (median [IQR], 16 [11-21]). After balancing preoperative CA19-9 levels, adjuvant chemotherapy, histological grade, T stage, and nodal stage, 174 pairs of patients were identified in the PSM cohort. The median OS was 29.6 (interquartile range, 15.7-61.4) months and 27.0 (interquartile range, 14.7-51.5) months in RAMPS and SDP, respectively. RAMPS was not associated with a survival benefit relative to SDP (hazard ratio, 0.87; 95% CI, 0.64-1.19; and p = 0.38). No significant difference in OS was observed between patients with a negative anterior margin (adjusted hazard ratio, 0.72; 95% CI, 0.45-1.15, and p = 0.17) and without nodal metastasis (adjusted hazard ratio, 0.93; 95% CI, 0.54-1.61; and p = 0.79). RAMPS can obtain better oncological outcomes but is not associated with improved long-term survival compared with SDP. Regarding a negative anterior margin or without nodal involvement, RAMPS may be an optimal operation to strive for R0 resection.