The role of sarcopenia and myosteatosis in early-onset colorectal cancer prognosis: an international multicenter prospective cohort study

BACKGROUND: Although patients with early-onset colorectal cancer (EOCRC) share characteristics with the general colorectal cancer population, they also exhibit distinct features. Parameters such as sarcopenia, myosteatosis, and overall body composition play a crucial role in disease progression. This study aimed to assess the impact of body composition on oncological prognosis. METHOD: Patients were recruited from the Humanitas Research Hospital (Milan, Italy) and the Spanish Early-Onset Colorectal Cancer Consortium (SECOC) prospective multicenter study. Preoperative computed tomography scans were analyzed between January 2019 and December 2023. Skeletal muscle mass index, visceral adipose tissue cross-sectional area, and intermuscular and intramuscular adipose tissues at the level of the transverse processes of the third lumbar vertebra (L3) were measured. Sarcopenia, obesity, and myosteatosis were defined according to sex-specific and body mass index cutoff points. RESULTS: After analyzing 197 patients, the mean age at diagnosis was 42.16 ± 6.1 years. According to the colorectal tumor characteristics, 64% of the tumors were located in the colon (n = 126). After analysis of radiological body characteristics, the prevalence of sarcopenia was 61.9% and myosteatosis was 40.1%. Overall and disease-free survival analysis identified, among other factors, psoas muscle index [hazard ratio (HR) 0.67, 95% CI 0.53-0.85], sarcopenia (HR 2.09, 95% CI 1.06-4.14), and myosteatosis (HR 2.29, 95% CI 1.25-4.19) as independent factors implicated in oncological prognosis. CONCLUSION: EOCRC patients showed a high prevalence of sarcopenia and myosteatosis, similar to that described in elderly cohorts. This deficiency in muscle quality and quantity was a risk factor for recurrence and mortality during the follow-up of their neoplasia.