Distinct cachexia phenotypes and the importance of adipose tissue loss on survival of patients with advanced pancreatic cancer on FOLFIRINOX chemotherapy

Abstract

By the traditional definition of unintended weight loss, cachexia develops in ~80% of patients with pancreatic ductal adenocarcinoma (PDAC). Here we measure the longitudinal body composition changes in patients with advanced PDAC undergoing FOLFIRINOX therapy. We performed a retrospective review of 53 patients with advanced PDAC on FOLFIRINOX as first line therapy at Indiana University Hospital from July 2010 to August 2015. Demographic, clinical, and survival data were collected. Body composition measurement, trend, univariate and multivariate analysis were performed. Three cachexia phenotypes were identified. The majority of patients, 64%, had Muscle-and-Fat Wasting (MFW), while 17% had Fat-Only Wasting (FW) and 19% had No Wasting (NW). NW had significantly improved overall median survival (OMS) of 22.6 months vs. 13.0 months for FW and 12.2 months for MFW (p=0.02). FW (HR=5.2; 95%CI=1.5-17.3) and MFW (HR=1.8; 95%CI=1.1-2.9) were associated with an increased risk of mortality compared to NW. OMS and risk of mortality did not differ between FW and MFW. Progression of disease, sarcopenic obesity at diagnosis, and primary tail tumors were also associated with decreased OMS. On multivariate analysis cachexia phenotype and chemotherapy response were independently associated with survival. Three phenotypes of cachexia were observed. Moreover, three phenotypes suggests molecular or genetic heterogeneity of host or tumor. Identifying these differences will be vital to defining optimal treatment for cachexia. Survival among FW was as poor as MFW suggesting adipose tissue plays a crucial role in cachexia. Blunting or possibly preventing cachexia may confer a significant survival advantage in patients with advanced PDAC.