Optimizing Indications for Conversion Surgery Based on Analysis of 454 Consecutive Japanese Cases with Unresectable Pancreatic Cancer Who Received Modified FOLFIRINOX or Gemcitabine Plus Nab-paclitaxel: A Single-Center Retrospective Study.

Abstract

The prognosis of initially unresectable pancreatic cancer (UR-PC) has improved since the introduction of FOLFIRINOX (FFX) or gemcitabine plus nab-paclitaxel (GNP) treatment. Nonetheless, the indications and optimal timing for conversion to resection remain unclear for UR-PC. The aim of this study is to evaluate the characteristics of cases with initially UR-PC who received modified FFX or GNP treatment. This retrospective study reviewed 454 consecutive Japanese UR-PC cases who received modified FFX/GNP treatment. Cases were categorized according to resection status, and overall survival (OS) was evaluated using a multivariable prognostic scoring model (0-4 points, higher score indicating more favorable prognostic factors). The overall resection rate was 16% for locally advanced UR-PC (UR-LA) and 5% for metastatic UR-PC (UR-M). The resection group had better OS than the nonresection group (median OS time: not reached versus 13.0 months, P < 0.001). The independent prognostic factors were normalized CA19-9 concentration, modified Glasgow prognostic score of 0, tumor shrinkage after chemotherapy, chemotherapy duration ≥ 8 months, and resection. Cases were grouped according to their prognostic score, and the results suggested that candidates for resection might have prognostic scores of 4 points in UR-M cases or 2-4 points in UR-LA cases. Stratification according to prognostic score was useful in predicting the outcomes of UR-PC cases and may aid in identifying cases who might benefit from surgical treatment after responding to chemotherapy.