4025 Background: We showed in a previous work that “Patient Generated-Subjective Global Assessment” (PG-SGA) was independently associated with survival and treatment toxicities in non-pretreated metastatic colorectal cancer (mCRC) patients. We have evaluated here if muscle mass in these patients can provide useful additional information for clinical practice. The objective of the present work was to evaluate the association between baseline sarcopenia, and the variation of the Skeletal Muscle Index (SMI) under treatment with survival and chemotherapy-related toxicities in our population of non-pretreated mCRC patients. Methods: This prospective multicenter observational study enrolled non-pretreated mCRC patients. Measurement of SMI was performed on routine CT scan at day 0 (D0) and day 60 (D60). PG-SGA score and other nutritional factors were collected at D0. Progression-free survival (PFS) and overall survival (OS) were calculated from treatment start. Treatment related toxicities were registered according to the NCI CTCAE v4.0. Results: 149 patients were included in eight French centers from 7/2013 to 11/2016. Sarcopenia at baseline was not significantly associated with survival outcomes or chemotherapy-related toxicities. The best cut-point value of SMI variation (between D0 and D60) for OS prediction obtained with a log-rank maximisation method was -14%. The decrease in SMI > 14%, with a median follow-up of 23 months, was significantly associated with shorter PFS (6 vs 9 mo; HR 1.8, 95%CI 1.1-3.1, p = 0.02) and OS (8.5 vs 26 mo; HR 2.4, 95%CI 1.3-4.4, p = 0.004), independently of hypoalbuminemia and malnutrition defined by PG-SGA, in multivariate analysis. 40% of patients with a SMI decrease > 14%, and 22% of patients with a SMI increase or stable or decrease < 14% developed grade ≥ 2 clinical toxicities (OR 3.0, 95%CI 1.2-7.7, p = 0.02), but the difference was not statistically significant in multivariate analysis (OR 2.3. 95%CI 0.8-6.7, p = 0.1). Conclusions: To our knowledge, this study is the first study assessing the association of skeletal muscle loss with survival and treatment toxicities in patients with mCRC prospectively. In our population of non pre-treated mCRC patients, baseline sarcopenia was not associated with poor survival outcomes, but the decrease in SMI > 14% during the first two months of treatment was significantly associated with decreased PFS and OS, independently of other prognostic and nutritional factors.
Baseline Sarcopenia and Skeletal Muscle Loss During Chemotherapy Affect Survival Outcomes in Metastatic Gastric Cancer
