Outcomes of nodal upstaging comparing video-assisted thoracoscopic surgery versus open thoracotomy for lung cancer

In early stage non-small cell lung cancer, the optimal surgical approach for lymph node dissection remains controversial. Without a uniform standard for the quality of lymph node dissection, outcomes of nodal upstaging comparing video-assisted thoracoscopic surgery (VATS) versus open thoracotomy (OPEN) also remain controversial. Thus, we compared the clinical outcomes of nodal upstaging between each approach.

We retrospectively evaluated 1319 surgically resected lung cancer cases between 2008 and 2017 at our institute. Moreover, 348 VATS and 348 OPEN cases were extracted using propensity score matching. We investigated the frequency, prognosis, and post-recurrence course of nodal upstaging between each approach.

A total of 193 nodal upstaging cases were identified. Nodal upstaging was more frequent in the OPEN group (24 %) than the VATS group (9%) (p < 0.001). However, multivariable analysis revealed the surgical approach was not significantly associated with nodal upstaging (OPEN: odds ratio, 1.3; 95 % confidence interval, 0.93-2.02; p = 0.108) and, after matching, nodal upstaging with each approach were of equivalent frequency (p = 0.752). The median follow-up period was 5.0 years. Nodal upstaging was an independent prognostic factor for worse overall survival, cancer-specific survival, and recurrence-free survival in multivariable analyses (all p < 0.001). Of all cases, 222 recurred after surgery. There were no significant differences in recurrence patterns and initial recurrence sites depending on surgical approach. The 5-year post-recurrence survival rate was 52 % after VATS and 30 % after OPEN; however, this difference was not statistically significant (p = 0.052). Moreover, post-recurrence survival rate was not significantly different between the VATS and OPEN groups (pN0: p = 0.268, pN1: p = 0.437, and pN2: p = 0.144).

Outcomes of nodal upstaging between VATS and OPEN were found to be equivalent. The difference in the frequency of nodal upstaging was not due to inferior quality of lymph node dissection with VATS; rather, that difference resulted from selection bias.