Changes in body composition during neoadjuvant therapy can affect prognosis in rectal cancer patients: An exploratory study

Aim: To establish the correlation between changes in body composition after neoadjuvant chemoradiotherapy (nCRT) and postoperative outcomes, in patients with advanced low rectal cancer. Methods: Patients with clinical stage T≥3 or N+ rectal cancer who underwent nCRT and surgical resection were studied. Skeletal muscle, visceral, and subcutaneous fat cross-sectional area were measured by computed tomography before and after nCRT. Postoperative morbidity, pathologic response to nCRT, overall and disease-free survival was assessed. Results: Fifty-two patients, median age 62 (range 32-79) were studied. A skeletal muscle loss >2% significantly correlated with a shorter disease-free survival both in the overall population (P = 0.048) and in the subgroup of N0 patients (P = 0.048). A subcutaneous fat loss >5% was also associated with a shorter disease-free survival (P = 0.012) in the whole population. Conclusions: Skeletal muscle loss, after neoadjuvant chemoradiotherapy, negatively impacts on disease-free survival in surgically treated rectal cancer patients.