Prognostic factors in patients with locally advanced or borderline resectable pancreatic ductal adenocarcinoma: chemotherapy vs. chemoradiotherapy

Abstract

Purpose: To identify common and unique pre-treatment prognostic factors in patients with borderline resectable (BR) or locally advanced (LA) pancreatic ductal adenocarcinoma (PDAC), treated with chemotherapy (CTx) or concurrent chemoradiotherapy (CRT).

Methods: We enrolled 215 patients with BR/LA PDAC, who were treated with either CTx (n = 82) or CRT (n = 133) as a first-line treatment between 2013 and 2016. Clinical data and CT imaging findings for predicting overall survival (OS) and progression-free survival (PFS) were analyzed using Cox regression analysis.

Results: Carbohydrate antigen (CA) 19-9 > 1000 U/mL (hazard ratio [HR] 1.91; p = 0.001) and non-homogeneous enhancement (HR 1.95; p < 0.001) were associated with shorter OS in all study populations. There was no significant difference in median OS (15.3 vs 16.8 months, p = 0.297) and PFS (10.0 vs 11.7 months, p = 0.321) between the CTx and CRT groups. Non-homogeneous enhancement (HR 2.04; p = 0.006) and presence of positive lymph node on CT (HR 2.38; p = 0.036) were associated with poor OS in the CTx group, while CA 19-9 > 1000 U/mL (HR 2.38; p = 0.001) and non-homogeneous enhancement (HR 1.73; p = 0.006) were independent predictors for poor OS in the CRT group.

Conclusion: Enhancement pattern on CT was a common prognostic factor for patients with PDAC treated with either CTx or CRT. Presence of positive lymph nodes on CT was a poor prognostic factor for the CTx group only, whereas CA 19-9 > 1000 U/mL was a poor prognostic factor for the CRT group only.