Cancer cachexia occurs in patients with far advanced disease. It is known to be a prognostic factor for poor survival and is almost impossible to reverse. Therefore, early detection and prevention are essential. Sarcopenia, usually based in oncology on skeletal muscle mass loss, is a component of cachexia and an independent prognostic factor for the efficacy and toxicity of cancer therapies and a negative predictor for survival. Using CT to measure the muscular surface area at the third lumbar, vertebra (L3) section is of great interest in low skeletal muscle mass (LSMM) detection.

LSMM is not yet systematically screened for in routine oncology practice, and the clinical evaluation of weight and body mass index are not sufficient to diagnose it. Moreover, cancer treatments may lead to fat gain, with concerns that increasing fat mass may mask LSMM. This is the case for prostate cancer with androgen deprivation.

The Sarcopenia and Cancer Nutrition study was a French, national, cross-sectional study conducted across 29 centres to evaluate the prevalence of LSMM in patients with metastatic cancer, by estimating the skeletal mass index (SMI) from the cross-sectional muscle surface area at the L3 level. The main results and methodology have been detailed in a recent publication.1 In this letter, we highlight the results for a subgroup of patients with metastatic prostate cancer, with recommendations for improving current practice.

The patients in this study were adults undergoing ambulatory medical treatment …