Long‐term changes in psoas muscle mass after lobectomy and segmentectomy for early‐stage lung cancer

Abstract

BackgroundSegmentectomy is considered a less invasive procedure than lobectomy for patients with non‐small cell lung cancer (NSCLC); however, little is known about the physiological mechanism underlying the lower invasiveness of segmentectomy. This study is aimed to compare the differences in the long‐term changes in the psoas muscle mass after segmentectomy and lobectomy in patients with NSCLC.MethodsOverall 315 recurrence‐free patients who underwent segmentectomy (n = 93) or lobectomy (n = 222) for clinical stage 0‐I NSCLC between January 2016 and December 2018 and underwent computed tomography during the entire period of 6 months ≤ postoperative year (POY) 0.5 < 12 months, 12 months ≤ POY 1 < 24 months, 24 months ≤ POY 2 < 36 months, and 36 months ≤ POY 3 < 48 months were included. Bilateral psoas muscle area (PMA) at the L3 level was measured using each cross‐sectional computed tomography scan. Differences between the segmentectomy and lobectomy groups in the mean change of postoperative PMA from the preoperative period were analysed using Student's t‐test and mixed analysis of variance. Multivariable analysis was performed to identify the risk factors for PMA loss on POY 3 using logistic regression analysis.ResultsThe lobectomy group had a significantly larger PMA change than the segmentectomy group during each postoperative period (P < 0.001). Mixed analysis of variance revealed that the mean PMA change was significantly smaller in the segmentectomy group than in the lobectomy group during the observation period (P < 0.001). The mean change in the PMA was significantly larger from POY1 (−2.5%) to POY2 (−3.9%) and POY3 (−4.7%) in the lobectomy group (P = 0.003 and P < 0.001). However, PMA remained unchanged during the postoperative observation period in the segmentectomy group. In the multivariable analysis, the risk factors for PMA change ≤−3.3% (cut‐off: mean change of PMA) at POY3 included lobectomy [odds ratio (OR), 3.32; 95% confidence interval (CI), 1.90–5.82; P < 0.001], male sex (OR, 1.92; 95% CI, 1.02–3.62; P = 0.044) and open thoracotomy (OR, 1.84; 95% CI, 1.11–3.05; P = 0.017). After propensity score matching, the mean change in PMA was smaller in the segmentectomy group (n = 75) than in the lobectomy group (n = 75) during the postoperative observation period (P < 0.001).ConclusionsPsoas muscle mass was better maintained during the postoperative period by segmentectomy than by lobectomy. Psoas muscle mass reduction progressed over a long postoperative period after lobectomy. Segmentectomy via complete video‐assisted thoracic surgery is associated with a lower likelihood of sarcopenia progression.