A retrospective cohort study to investigate the incidence of cancer-related weight loss during chemotherapy in gastric cancer patients

PURPOSE: This study aimed to evaluate cancer-related weight loss (WL) after the start of first-line chemotherapy as a surrogate marker for cancer cachexia in patients with advanced gastric cancer. We investigated the incidence of WL and the relationship between WL and overall survival (OS) or adverse events. METHODS: We conducted a retrospective cohort study in 131 patients with advanced gastric cancer who received first-line systemic chemotherapy between September 1, 2010, and August 31, 2016, at Kurume University Hospital and Shizuoka Cancer Center Hospital. WL was defined in this study as weight loss of > 5% or weight loss of > 2% with a body mass index of < 20 kg/m(2) within the last 6 months after the start of chemotherapy. RESULTS: Median age and median Eastern Cooperative Oncology Group performance status of the patients participating in this study were 68 years old and 0, respectively. Incidence of WL was 53% at the first 12 weeks after starting first-line chemotherapy, and increased to 88% after 48 weeks. Overall survival rates were significantly associated with WL at 12, 24, and 48 weeks. Appetite loss and fatigue were more frequent and more severe in patients with WL. CONCLUSION: WL was especially observed in more than half the patients within 12 weeks after starting chemotherapy. WL appeared to relate to adverse events or reduced survival. These results suggest the importance of monitoring WL or providing nutritional support at the beginning of chemotherapy. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s00520-020-05479-w) contains supplementary material, which is available to authorized users.