Prognostic Impact of a Decrease in Serum Carbohydrate Antigen 19-9 Levels After Preoperative Therapy for 4 Months or More for Borderline Resectable Pancreatic Cancer Abutting Major Arteries.

ABSTRACT

Background: This study aimed to identify the prognostic factors after pancreatectomy for borderline resectable pancreatic cancer abutting major arteries (BR-A).Methods: We retrospectively investigated relationship between preoperative and intraoperative variables and overall survival (OS) through univariate and multivariate analyses. The cut-off points of preoperative therapy duration and response rates of serum carbohydrate antigen 19-9 (CA19-9) levels after preoperative therapy were determined through a minimum P-value approach using the log-rank test for OS. Overall survival was compared among patients stratified according to the independent prognostic factors and the presence or absence of pancreatectomy.Results: After pretreatment, 17 patients underwent pancreatectomy and four patients continued chemotherapy without surgery. Multivariate analysis in 17 resected BR-A patients demonstrated decreased serum CA19-9 levels and preoperative therapy duration of ≥4 months were the independent prognostic factors [hazard ratio (HR) 0.01; P = 0.002, HR 0.13; P = 0.02]. Patients who underwent surgery with decreased serum CA19-9 levels after preoperative therapy of ≥4 months had a significantly better prognosis than those without one or both of independent prognostic factors and those who did not undergo surgery (median survival time not estimated, 23.3 months, 10.5 months, and 10.8 months; P = 0.02, P = 0.004, and P = 0.001, respectively). Furthermore, the prognosis did not significantly differ between the patients who underwent surgery without meeting either one or both criteria and those without surgery.Conclusions: Preoperative therapy duration of ≥4 months and decreased serum CA19-9 levels are independent prognostic factors among BR-A patients.