Faculty Bibliography

OBJECTIVES: Sublobar resection is advocated for patients with NSCLC and compromised cardiopulmonary reserve, and for selected patients with early stage disease. Anatomic segmentectomy (AS) has traditionally been considered superior to wedge resection (WR), but well-balanced comparative studies are lacking. We hypothesize that WR and AS are associated with comparable oncologic outcomes for patients with cT1N0 NSCLC. METHODS: A retrospective review of a prospective database was performed (2000-2014) for cT1N0 patients, excluding patients with multiple primary tumors, carcinoid tumors, adenocarcinoma in situ, and minimally invasive adenocarcinoma. Demographic, clinical, and pathological data were reviewed. Overall survival (OS) and disease-free survival (DFS) were estimated using the Kaplan-Meier method and differences compared using log-rank test. Multivariable analysis (MVA) of factors affecting DFS was performed by Cox regression analysis. For further comparison of the effect of resection type on survival, propensity score matching (i.e., by age, sex, Charlson comorbidity index, percent forced expiratory volume in 1 second (FEV1%), clinical tumor size, and tumor maximum standardized uptake value) was performed to obtain balanced cohorts of patients undergoing WR and AS (n = 76 per group). RESULTS: Two hundred eighty-nine patients met our selection criteria, including WR in 160 and AS in 129. Poor performance status and limited cardiopulmonary reserve were the primary indications for sublobar resection in 76% of WR patients and in 62% of AS patients (p = 0.011). Thirteen patients (4.5%) had pN1/2 disease. Patients undergoing AS were more likely to have nodal sampling/dissection [123 (95%) versus 112 (70%); p < 0.001], more stations sampled (3 versus 2; p < 0.001), and more total nodes resected (7 versus 4; p = 0.001). However, there was no difference between patients undergoing WR versus AS in local recurrence [15 versus 14; p = 0.68] or 5-year DFS (51% versus 53%; p = 0.7; median follow-up 34 months). Univariate analysis showed no effect of extent of resection on DFS [hazard ratio 1.07 (95% confidence interval 0.74-1.56); p = 0.696]. MVA showed that only tumor maximum standardized uptake value was associated with worse DFS [hazard ratio 1.07 (95% confidence interval 1.01-1.13); p = 0.016]. In the propensity-matched analysis of balanced subgroups, there was also no difference (p = 0.950) in 3- or 5-year DFS in cT1N0 patients undergoing WR (65% and 49%) or AS (68% and 49%). CONCLUSIONS: Our data show that WR and AS are comparable oncologic procedures for carefully staged cT1N0 NSCLC patients. Although AS is associated with a more thorough lymph node dissection, this did not translate to a survival benefit in this patient population with a low rate of nodal metastases.