Less is more in solid-dominant lung cancer? Sublobar resection versus lobectomy for solid-dominant stage IA non-small-cell lung cancer: A meta-analysis study

Although lobectomy is well established as the standard surgical procedure for stage IA non-small-cell lung cancer (NSCLC), sublobar resection is increasingly preferred, particularly in intentional segmentectomy for radiologically less-invasive small NSCLC. However, the indication for sublobar resection of radiologically pure solid or solid-dominant NSCLC remains controversial, owing to its invasive pathological characteristics. Therefore, the present meta-analysis was conducted to compare the efficacy of sublobar resection with lobectomy for treating solid-dominant stage IA NSCLC. An electronic search was conducted using four online databases from their dates of inception to April 2017. The hazard ratio (HR) was used as a summary statistic for censored outcomes and the odds ratio (OR) was used as the summary statistic for dichotomous variables. A total of nine studies met the selection criteria, including a total of 2,265 patients (1,728 patients underwent lobectomy, 425 segmentectomy and 112 wedge resection). From the available data, patients treated with a sublobar resection had a higher risk of local recurrence compared with patients treated with lobectomy [OR=1.89; 95% confidence interval (CI), 1.02-3.50; P=0.04]. However, no obvious difference in local recurrence was found in a subgroup analysis of segmentectomy compared with lobectomy (OR=1.19; 95% CI, 0.68-2.10; P=0.61). Sublobar resection was not associated with a significantly negative impact on distant recurrence (OR=1.09; 95% CI, 0.55-2.16; P=0.796). Patients in the sublobar resection group had no significant differences in recurrence-free survival (RFS; HR=1.43; 95% CI, 0.76-2.69; P=0.27) and overall survival (OS; HR=0.96; 95% CI, 0.75-1.23; P=0.77) compared with those in the lobectomy group. In the subgroup analysis of anatomic segmentectomy compared with lobectomy, there was no significant difference in RFS, with mild inter-study heterogeneity. The current meta-analysis suggested that segmentectomy had a comparable oncologic efficacy to lobectomy for solid-dominant stage IA NSCLC. Therefore, segmentectomy may be a feasible alternative in selected cases of solid-dominant stage IA NSCLC. However, these findings should be confirmed by prospective randomized controlled trials in the future.