Can Wedge Resection Supplant Segmentectomy for Small Peripheral NSCLC?

Recent randomized controlled trials have confirmed that sublobar resection is not inferior to lobectomy in treating small peripheral non-small cell lung cancer. Sublobar resection includes both wedge resection and segmentectomy. Although wedge resection is a simpler and less invasive procedure without the dissection of hilar structures compared to segmentectomy, it may be associated with a higher rate of local recurrence. The superiority of either surgical procedure still remains uncertain. In general, wedge resection provides advantages over segmentectomy in terms of postoperative complications and the length of hospital stay. Wedge resection is a curable option for tumors with an expected 5-year recurrence-free survival of 100% such as pure ground-glass opacity and intraoperatively-diagnosed adenocarcinoma in situ/minimally invasive adenocarcinoma. For peripheral lung tumors with consolidation-to-tumor ratio (CTR) ≤0.25 and maximum diameter ≤2 cm, wedge resection is recommended. JCOG 1211 included tumors with 0.25 < CTR ≤ 0.5 and diameter ≤2 cm and investigated the efficacy of segmentectomy for radiologically invasive lung adenocarcinoma, but 58% of enrolled patients turned out to be pre-invasive adenocarcinoma. At least 47% of patients from JCOG 1211 underwent unnecessary segmentectomy and wedge resection could have been sufficient. Frozen-section examinations can aid in determining the adequacy of wedge resection in this group. For tumors with CTR >0.5 and diameter ≤2 cm wedge resection may be considered if adequate resection margins and negative lymph node metastasis can be guaranteed. Further research is warranted to better elucidate the optimal sublobar procedure.