Impact of surgical margin after sublobar resection of lung cancer: a narrative review

BACKGROUND AND OBJECTIVE: The use of low-dose computed tomography for screening has improved the detection of early-stage lung cancers. In addition, two large clinical studies have recently reported good outcomes of sublobar resection for early-stage lung cancers, increasing the need for limited resection. However, locoregional recurrence is an important issue in sublobar resection, and R0-resection with sufficient surgical margin is essential to prevent recurrences. This study aimed to investigate the suitable surgical margin distance after sublobar resection of lung cancers with a review of the literature. METHODS: We used the PubMed interface to search the Medline database for retrieving literature related to surgical margin after sublobar resection published between 2003 and 2023. KEY CONTENT AND FINDINGS: Overall, 175 papers were found; of them, we investigated the outcomes of 18 selected papers. The correlation between the actual surgical margin distances and recurrences was evaluated in seven articles. All the articles, except one, indicated that an increased margin distance was associated with survival and a lower risk of locoregional recurrence. Further, a surgical margin of 9–15 mm was reported to be sufficient. The correlation between the margin-tumor ratio (M/T) and recurrences was investigated in six articles, most of which demonstrated that the ratio of <1 would be a remarkable predictor of recurrence or poor survival. Although the correlation between surgical margin and spread through air spaces (STAS) was discussed in four articles, their findings remain debatable. CONCLUSIONS: A surgical margin of >10 mm or M/T of ≥1 would be necessary for sublobar resection for STAS-negative early-stage non-small cell lung cancer, although it is difficult to draw a definite conclusion about the appropriate surgical margin because of the characteristics of available literature (mainly retrospective, with different inclusion criteria and surgical margin measurement methods).