Does surgical margin affect recurrence and survival after pulmonary segmentectomy for cT1 lung cancer?

Background: During segmentectomy for early-stage non-small cell lung cancer (NSCLC), it is advised that the tumor be at least 1 cm away from the intersegmental plane, with a margin-to-tumor (M/T) ratio of at least 1. This study aims to investigate how surgical margin influences the risk of recurrence and overall survival (OS) following pulmonary segmentectomy. Methods: This is a single-center study including consecutive patients who underwent pulmonary segmentectomy for cT1N0M0 NSCLC between January 2017 and December 2022. Surgical margin distance and M/T ratio were measured on deflated lung specimens and analyzed as predictors of recurrence-free survival (RFS) and OS. Results: In total, 291 patients (median age: 69 years) underwent segmentectomy for cT1a (n=65), cT1b (n=152) and cT1c (n=74) cN0 NSCLC. Surgical approach was performed by video-assisted thoracoscopic surgery in 99% and conversion thoracotomy was necessary in 2.4%. Single segmentectomy was performed in 183 patients (63%). The median number of dissected lymph nodes was 7 [interquartile range (IQR), 4-12]. The median size of tumor was 15 (IQR, 11-20) mm. The median surgical margin was 13 (IQR, 7-22) mm and 32% of patients had surgical margin of less than 10 mm with only one patient with R1 resection. M/T ratio >1 was achieved in 49%. Nodal upstaging was found in 14 patients (5%). During the follow-up, 63 patients (21%) were lost and removed from analyses. Local recurrence was observed in only 3 patients (1%) and distant in 19 patients (8%). RFS was significantly associated with positron emission tomography (PET) fluorodeoxyglucose (FDG) uptake >3 [hazard ratio (HR) =4.89], pleural invasion (HR =3.02) and nodal upstaging (HR =3.79). However, surgical margin <10 mm or ratio <1 were not correlated with increased local recurrence (HR =0.78; P=0.62) (HR =0.69; P=0.40) or poorer survival (HR =1.14; P=0.81) (HR =1.73; P=0.31), respectively. Conclusions: Local recurrence remains infrequent after pulmonary segmentectomy for cT1N0 NSCLC even after limited surgical margin.