Skeletal Muscle Loss Is an Imaging Biomarker of Outcome after Definitive Chemoradiotherapy for Locally Advanced Cervical Cancer.

Purpose: This study investigates the association between body composition change during concurrent chemoradiotherapy (CCRT) and outcome in patients with locally advanced cervical cancer (LACC).Experimental Design: Pre- and posttreatment CT images of 245 patients with LACC who were treated between 2004 and 2015 were analyzed. Skeletal muscle index (SMI) and density (SMD), subcutaneous adipose tissue index (SATI), and visceral adipose tissue index (VATI) were measured from two sets of CT images at the level of the L3 vertebra. Sarcopenia and a low SMD were defined using published cut-off points. Predictors of overall survival (OS) and cancer-specific survival (CSS) were analyzed using Cox regression models.
Results: The median follow-up was 62.7 (range, 7.3-152.3) months. Among the 245 patients, 127 (51.8%) had pretreatment sarcopenia, and 154 (62.9%) had a low SMD. SMI did not decrease significantly during CCRT, 0.6%/150 days [95% confidence interval (CI), -1.8-0.6; P = 0.35]. However, SMI loss during CCRT of >10.0%/150 days was independently associated with poorer OS (HR, 6.02; 95% CI, 3.04-11.93; P < 0.001) and CSS (HR, 3.49; 95% CI, 1.44-8.42; P = 0.006) when adjusted for FIGO stage, pathology, and treatment. Pretreatment sarcopenia and change of SMD, SATI, and VATI during CCRT were not associated with survival.Conclusions: Skeletal muscle measurements could be imaging biomarkers to predict outcomes for patients with LACC in clinical practice. Further studies are needed to determine whether multimodal interventions can preserve skeletal muscle mass and thereby improve survival. Clin Cancer Res; 24(20); 5028-36. ©2018 AACR. ©2018 American Association for Cancer Research.