A Retrospective Cohort Study to Investigate the Incidence of Cachexia During Chemotherapy in Patients with Colorectal Cancer.

INTRODUCTION This retrospective study focused on cancer cachexia in clinical practice. We evaluated the incidence of cancer cachexia and the relationship between cancer cachexia and overall survival (OS) or toxicities in patients with advanced colorectal cancer after undergoing first-line systemic chemotherapy. METHODS We examined 150 patients with colorectal cancer who underwent first-line systemic chemotherapy between February 1, 2010 and August 31, 2016 at Shizuoka Cancer Center Hospital and Kurume University Hospital. Cancer cachexia was defined as > 5% weight loss or > 2% weight loss with a body mass index of < 20 kg/m2 within the past 6 months according to the European Palliative Care Research Collaborative criteria. RESULTS One hundred patients from Shizuoka Cancer Center and 50 from Kurume University Hospital were registered. Median age and body mass index were 65 years (range 29-85) and 21.7 kg/m2 (14.8-32.5), respectively. Cumulative incidence of cancer cachexia was 50.7% at 24 weeks, and reached 91.3% over the whole study period. OS was significantly different between patients with and without cancer cachexia within 24 weeks after starting first-line treatment, although the onset of cancer cachexia within 24 weeks could not be considered as an independent prognostic factor for OS. Severe appetite loss and fatigue tended to occur more frequently in patients with cancer cachexia within 24 weeks. CONCLUSION Cancer cachexia appears to have an onset in approximately half of patients with advanced colorectal cancer within 24 weeks after starting first-line treatment. Although causal relationships were controversial, the onset of cancer cachexia within 24 weeks tends to be related to worse outcomes. Thus, it would be better to monitor weight loss leading to cachexia in patients with advanced colorectal cancer, especially within 24 weeks after starting first-line chemotherapy. TRIAL REGISTRATION University Hospital Medical Information Network Clinical Trials Registry (UMIN000035002).