Is segmentectomy actually superior to lobectomy for early-stage lung cancer? A discrepancy between the JCOG0802 trial...

To evaluate whether results of the JCOG0802/WJOG4607L trial, which demonstrated the superiority of segmentectomy over lobectomy in terms of overall survival for patients with peripheral small-sized lung cancer, are applicable to clinical practice.

In this single-center retrospective analysis, we categorized patients who underwent lobectomy or segmentectomy during the enrollment period of the JCOG0802/WJOG4607L trial into 3 groups: patients enrolled in the trial (Cohort A), patients who were eligible but not enrolled (Cohort B), and ineligible patients (Cohort C). We assessed whether trial participants reflected typical patients seen in clinical practice (representativeness) and whether trial results could be applied in routine practice (generalizability) by comparing patient characteristics and survival between cohorts, using Cohort A as the reference.

Cohorts A, B, and C included 91, 163, and 81 patients, respectively. Overall survival at 5 years was 91.2% (95% confidence interval [CI], 83.1%-95.5%), 93.9% (95% CI, 88.5%-96.8%), and 87.7% (95% CI, 77.7%-93.4%), respectively, with no significant different among the 3 cohorts (P = .269). Hazard ratios for segmentectomy over lobectomy were 0.125 (95% CI, 0.015-0.987) in Cohort A, 0.281 (95% CI, 0.036-2.147) in Cohort B, and 1.806 (95% CI, 0.573-5.690) in Cohort C, indicating that the results observed in Cohort A were not replicated in Cohort B.

In this single-center retrospective study, segmentectomy was associated with numerically improved overall survival rates than lobectomy in JCOG0802-eligible patients not enrolled in the trial, although the difference was not statistically significant. Given the study's retrospective nature and underpowered statistics with a small sample size, these findings should be interpreted cautiously.