Nowadays, the role of segment resection in the treatment of non-small cell lung cancer ≤ 2 cm in the outer third of the lung field has been evaluated in multiple studies. Recently, professor Hisao Asamura released the long-term results of the JCOG0802 project in AATS 2021. Segmentectomy had a higher 5-year overall survival (94.3% vs. 91.1%) than lobectomy (P \< 0.001) for non-small cell lung cancer ≤ 2 cm (CTR \> 0.5) in the outer third of the lung field. However, a substantial portion of lung nodules was not located in the outer third, but the middle third of the lung field. Whether segmentectomy has non-inferiority long-term oncological effects compared to lobectomy for early-stage non-small cell lung cancer ≤ 2 cm in the middle third of lung field remains unclear. This randomized controlled trial study aims to investigate whether segmentectomy has non-inferiority long-term oncological effects compared to lobectomy for early-stage non-small cell lung cancer ≤ 2 cm in the middle third of the lung field.
