Low thoracic muscle mass index on computed tomography predicts adverse outcomes following lobectomy via thoracotomy for lung cancer

OBJECTIVES: The aim of this study was to determine whether the preoperative thoracic muscle mass is associated with postoperative outcomes in patients undergoing lobectomy via thoracotomy for lung cancer. METHODS: Consecutive patients undergoing lobectomy were retrospectively reviewed. The thoracic muscle mass index (TMMI) was obtained at the level of the fifth thoracic vertebra on preoperative thoracic computed tomography (CT). Patients were analysed comparatively by being dividing into low and high muscle index groups by the median of sex-specific TMMI. The primary outcomes were the incidence of any or postoperative pulmonary complications. The secondary outcomes were postoperative intensive care unit (ICU) admission, length of stay (LOS) in the ICU, total hospital LOS, readmission and mortality. RESULTS: The study population consisted of 120 patients (63.69.8 years; 74% male). Each groups included 60 patients. Major complications occurred in 28.3% (34/120) and readmission in 18.3% (22/120) of patients. The adjusted multivariable analysis showed that each unit increase in TMMI (cm(2)/m(2)) was independently associated with the rates of less any complications [odds ratio (OR) 0.92, P=0.014], pulmonary complications (OR 0.27, P=0.019), ICU admission (OR 0.76, P=0.031), hospitalization for >6 days (OR 0.90, P=0.008) and readmission (OR 0.93, P=0.029). CONCLUSIONS: Low TMMI obtained from the preoperative thoracic CT is an independent predictor of postoperative adverse outcomes in patients following lobectomy via thoracotomy for lung cancer. TMMI measurements may contribute to the development of preoperative risk stratification studies in the future.