Preoperative pectoralis muscle radiodensity as a risk factor for postoperative complications after thoracoscopic lobectomy for non-small cell lung cancer.

Background: Skeletal muscle radiodensity is associated with postoperative complications in cancer. However, data on skeletal muscle radiodensity and postoperative complication risk in patients with non-small cell lung cancer (NSCLC) are scarce, and this study investigated the relationship between skeletal muscle radiodensity and postoperative complication risk in patients with NSCLC treated by thoracoscopic lobectomy.

Methods: Quantitative and qualitative measurements of the pectoralis muscle were performed on a single axial slice above the aortic arch in the precontrast computed tomography (CT) scan performed before surgery. Sex-specific cutoffs for the pectoralis muscle mass index (PMI) and pectoralis muscle radiodensity (PMD) were set at the lowest tertile. A Clavien-Dindo grade ≥ III within 30 days of the operation was considered as a major complication, and logistic regression analysis was performed to identify risk factors for postoperative complications.

Results: The records of 163 consecutive patients with NSCLC receiving first-line thoracoscopic lobectomy between March 2016 and October 2019 were retrospectively reviewed and the PMI was found to be positively correlated with PMD (P<0.001). The PMI and PMD were significantly higher in men than in women (both P<0.001), and 23 (14.1%) patients experienced major postoperative complications. The multivariate analysis showed that male sex (P=0.032), lower body mass index (BMI) (P=0.016), and low PMD (P=0.012) before surgery, but not low PMI, were independent risk factors for major postoperative complications.

Conclusions: Skeletal muscle quality but not muscle mass predicts major complications after thoracoscopic lobectomy for NSCLC. Skeletal muscle measures from the preoperative CT scan may be used to stratify patients with NSCLC into risk categories that can guide clinical decision-making.