Impact of measurement of skeletal muscle mass on clinical outcomes in patients with esophageal cancer undergoing esophagectomy after neoadjuvant chemotherapy

Background: Some studies have reported that sarcopenia is linked to clinical outcomes in multiple types of malignancies, but this association has not been established in esophageal cancer. We assessed how sarcopenia affects clinical outcomes of multidisciplinary treatments for esophageal cancer. Methods: We included 165 esophageal cancer patients who had undergone neoadjuvant chemotherapy followed by esophagectomy. Computed tomography was used for cross-sectional measurement of the psoas muscle at the third lumbar vertebra; we then calculated the height-adjusted psoas muscle index. Pre- and postneoadjuvant chemotherapy psoas muscle indices were evaluated for associations with neoadjuvant chemotherapy response and neoadjuvant chemotherapy-related adverse events and postoperative complications, in addition to survival. Psoas muscle index cutoffs were 6.36 cm(2)/m(2) for men and 3.92 cm(2)/m(2) for women. Results: Psoas muscle index decreased after neoadjuvant chemotherapy (from 7.17 to 6.96 cm(2)/m(2); P = .0008), and specifically in men (from 7.45 to 7.23 cm(2)/m(2); P = .0001) but not in women (from 5.21 to 5.17 cm(2)/m(2); P = .810). Preneoadjuvant chemotherapy psoas muscle index (low versus high) was associated with neoadjuvant chemotherapy response (response rate: 65.1% vs 80.3%; P = .0494) and neoadjuvant chemotherapy-related adverse events (neutropenia: 93.0% vs 78.7%; P = .0337; febrile neutropenia: 53.5% vs 34.3%; P = .0278; hyponatremia: 51.2% vs 31.2%; P = .0190). Post-neoadjuvant chemotherapy psoas muscle index correlated with postoperative rate of complications (56.9% vs 33.3%; P = .0046), especially pneumonia (31.4% vs 9.7% P = .0008). Psoas muscle index was not associated with survival. Conclusion: Cross sectional measures of sarcopenia before and after neoadjuvant chemotherapy could predict tumor response, neoadjuvant chemotherapy-related adverse events, and postoperative complications in multidisciplinary treatments for esophageal cancer. (C) 2019 Elsevier Inc. All rights reserved.