Mortality for robotic- versus video-assisted lobectomy treated stage I non-small cell lung cancer patients

Background To address the United States Food & Drug Administration’s recent safety concern on robotic surgery procedures, we compared short- and long-term mortality for stage I non-small cell lung cancer (NSCLC) patients treated by robotic-assisted thoracoscopic surgical lobectomy (RATS-L) versus video-assisted thoracoscopic surgical lobectomy (VATS-L). Methods From the National Cancer Database, we identified 18,908 stage I NSCLC patients who underwent RATS-L or VATS-L as the primary operation from 2010 to 2014. Cox proportional hazards models were used to estimate hazard ratios (HRs) for short- and long-term mortality using unmatched and propensity score-matched analyses. All statistical tests were two-sided. Results Patients treated by RATS-L had higher 90-day mortality than those with VATS-L (6.6% vs. 3.8%; P=.03) if conversion to open thoracotomy occurred. After excluding first-year observation, multiple regression analyses showed RATS-L was associated with increased long-term mortality, compared to VATS-L, in cases with tumor size ≤20 mm: HRs were 1.33 (95%CI: 1.15-1.55), 1.36 (95%CI: 1.17-1.58) and 1.33 (95%CI: 1.11-1.61) for unmatched, N:1 matched and 1:1 matched analyses, respectively, in the intention-to-treat analysis. Among patients without conversion to an open thoracotomy, the respective HRs were 1.19 (95%CI: 1.10-1.29), 1.19 (95%CI: 1.10-1.29) and 1.17 (95%CI: 1.06-1.29). Similar associations were observed when follow-up time started 18- or 24-months post-surgery. No statistically significant mortality difference was found for patients with tumor size >20 mm. These associations were not related to case volume of VATS-L/RATS-L performed at treatment institutes. Conclusions Patients with small (≤20 mm) stage I NSCLC treated with RATS-L had statistically significantly higher long-term mortality risk than VATS-L after one-year post-surgery.