Background: Preoperative muscle volume and body mass index (BMI) are associated with postoperative outcomes. Because esophagectomy for esophageal cancer (EC) is associated with high morbidity and because EC has a poor prognosis, this study investigated the association of preoperative skeletal muscle mass and nutritional status with postoperative outcomes.
Methods: The study analyzed 483 patients who underwent esophagectomy from 2009 to 2012. The cross-sectional area of the psoas muscle index (PMI) was measured at the third lumbar vertebral level using computed tomography. Clavien-Dindo classifications were used to analyze postoperative complications. Because skeletal muscle mass varies according to sex, all analyses were performed accordingly (390 males, 93 females).
Results: For male patients, BMI was a significant multivariate factor, and PMI, a univariate factor, predicted postoperative complications and overall survival (OS). Using a preoperative nutritional and muscular (PNM) score derived from BMI and PMI results (patients were allocated 1 point if their BMI was < 18.5 kg/m2 and 1 point if their PMI was < 600 mm2/m2, for a possible maximum total of 2 points), male patients were categorized as high risk (score 2), moderate risk (score 1), or low risk (score 0). In the low-risk group, anastomotic leakage was significantly less (p = 0.01), and the 3-year OS was significantly better (p < 0.01). On the other hand, in female patients, neither BMI nor PMI was a significant factor for postoperative outcomes.
Conclusions: For male patients, the PNM score is a promising tool for predicting postoperative outcomes and identifying patients requiring preoperative nutritional intervention and rehabilitation.