622. evaluation of the psoas muscle index on clinical outcomes in patients with esophageal squamous cell carcinoma receiving neoadjuvant chemotherapy

Abstract Some studies have reported that sarcopenia is linked to clinical outcomes in multiple types of malignancies. Muscle mass, defined as the psoas muscle index (PMI), is an important parameter of sarcopenia. However, the relationship between esophageal cancer and PMI has not been fully investigated, especially in patients receiving neoadjuvant therapy. We assessed how sarcopenia affects clinical outcomes of multidisciplinary treatments for esophageal cancer. We included 112 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 post-neoadjuvant chemotherapy psoas muscle index were evaluated for associations with postoperative complications, in addition to survival. Psoas muscle index (PMI) cutoffs were 6.0 cm2/m2 for men and 4.0 cm2/m2 for women. In this study, sarcopenia was defined based on the value of PMI. 63 patients (56.3%) were diagnosed with sarcopenia after receiving neoadjuvant chemotherapy (NAC). Patients with sarcopenia after NAC were significantly older than patients without sarcopenia. No significant difference was found in gender or ASA score. The rate of postoperative complication in the patients with sarcopenia was higher than that in the patients without sarcopenia (40.0% vs 24.5%; p=0.090). Especially, the rate of postoperative pneumonia in the patients with sarcopenia was significantly higher than that in the patients without sarcopenia (23.8% vs 6.1%; p=0.012). Cross sectional measures of sarcopenia after neoadjuvant chemotherapy could predict postoperative complications in multidisciplinary treatments for esophageal cancer. It is important to maintain or improve nutritional status by intervention from the time of neoadjuvant chemotherapy.