Association between progression-free survival and metal stent patency in patients with advanced pancreatic cancer

Background: Chemotherapy reportedly affects the patency of self-expandable metal stents (SEMSs) in patients with cancer. However, knowledge regarding the association between SEMS patency and progression-free survival (PFS) remains limited. This study aimed to assess PFS and SEMS patency in patients with advanced pancreatic cancer. Methods: Between January 2012 and June 2021, 74 patients with locally advanced or metastatic pancreatic cancer (MPC) were enrolled in the study. Patients received gemcitabine plus nab-paclitaxel (GnP) or fluorouracil, leucovorin, oxaliplatin, and irinotecan (FOLFIRINOX) as initial chemotherapy and SEMS within 1 month before or after the initial chemotherapy. Longer PFS was defined as PFS >= 7 months. Results: This study enrolled 38 male patients (51.4%); the mean age was 66.2 [95% confidence interval (CI), 63.7-68.6] years. Of the patients, 46 (62.2%) had MPC and 58 (78.4%) received FOLFIRINOX as the initial chemotherapy. Of the patients, 61 (82.4%) underwent endoscopic SEMS insertion. The median stent patency and PFS were 6.9 [interquartile range (IQR), 4.5-12.9] and 6.4 (IQR, 4.2-12.5) months, respectively; the median overall survival (OS) was 10.5 (IQR, 6.7-16.5) months. Of the clinical parameters assessed using multivariate analysis, shorter PFS [PFS < 7 months; hazard ratio (HR), 2.117; 95% CI, 1.020-4.393; P=0.044] and metastatic cancer (HR, 2.414; 95% CI, 1.159-5.018; P=0.019) were found to be associated with shorter SEMS patency. The median SEMS patency in patients with longer PFS and those with shorter PFS was 14.3 and 7.0 months (P=0.012), respectively, and that in patients with locally advanced cancer and those with metastatic cancer was 16.7 and 7.0 months (P=0.006), respectively. The coefficient of determination between stent patency and PFS was 0.624. Conclusions: SEMS patency may be associated with PFS in patients with advanced pancreatic cancer who receive GnP or FOLFIRINOX.