Impact of Frozen Section Pathology Examination of Surgical Margins in Sublobar Pulmonary Resections for Clinical Stage IA Non-small Cell Lung Cancer.

[BACKGROUND] Sublobar resections are a valid surgical option for many patients with clinical stage IA non-small cell lung cancer (NSCLC). However, assessment of planned lines of resection can be limited when done using robotic technology. Further, incomplete resections are associated with worse outcomes. This study evaluated routine frozen section pathology (FSP) evaluation of margins during sublobar resections for clinical IA NSCLC.

[METHODS] Patients with clinical stage IA NSCLC who underwent lung resections during 2018 to 2023 were reviewed. Only patients with a preoperative intention to undergo sublobar resection were included. FSP reports were compared with final pathology. Operative notes were reviewed to determine changes in surgical plan based on intraoperative FSP evaluation of margins.

[RESULTS] Of 1008 patients who underwent surgery, 642 (63.7%) had a preoperative plan to undergo sublobar resection. Median preoperative tumor size was 1.5 cm (interquartile range, 1.1-2.0 cm). A positive margin was identified in 8 patients (1.25%) intraoperatively or postoperatively. FSP successfully identified 7 of 8 patients (87.5%) intraoperatively, all corresponding to the parenchymal margin. In 5 of 7 patients (71.4%), the surgeon could alter the procedure to achieve a final negative margin. The final rate of non-R0 resection was 3 of 642 (0.47%). Therefore, FSP decreased the potential rate of non-R0 resection from 1.25% to 0.47% (62% reduction).

[CONCLUSIONS] FSP is a valuable tool to assess resection margins during intended sublobar resections of clinical stage IA NSCLC. Intraoperative margin analysis can identify most patients with positive margins, allowing the surgeon to alter the planned procedure, if appropriate, minimizing non-R0 resections.