S36 Multimodality treatment of resectable stage III (N2) lung cancer: is pneumonectomy out of the game?

Lung cancer resection by pneumonectomy in the presence of N2 disease has long been debated and non-surgical multimodality therapy often preferred. A more precise prognostic stratification of nodal disease was recently suggested by the International Association for the Study of Lung Cancer (IASLC) (J Thorac Oncol. 2015;10: 1675–1684). We therefore aimed to assess the impact of nodal spread patterns on long-term pneumonectomy outcomes. Methods We retrospectively reviewed all consecutive pneumonectomies performed at our institution for lung cancer over a 5-year period. Staging was adjusted to TNM 8thedition for all tumours. Pathological nodal status was subclassified as: N0, N1a (single-station), N1b (multi-station), N2a1 (single-station N2, with negative N1), N2a2 (single-station N2, with positive N1) and N2b (multi-station). Survival was assessed using Kaplan-Meier method log-rank test. Results 2226 major anatomical lung resections were performed between April 2014 and July 2019. Of these, we analysed 114(5.1%) pneumonectomy. Pathologic nodal stage was N0 in 41 patients (35.9%), N1a 24(21%), N1b 18(15.8%), N2a1 6(5.3%), N2a2 10(8.8%), N2b 15(13.2%). Patient characteristics (age, gender, side, Charlson comorbidity index, pT stage, histology) did not differ significantly amongst the groups. 5(4.4%) patients received neoadjuvant treatments. 30-day and 90-day mortality was 5(4.4%) and 8(7.0%). Median length of stay was 7 days(4–85). Incidence of bronchopleural fistula was 8(7%). R0 resection was achieved in 106(93%) cases, with 7(6.1%) receiving adjuvant radiotherapy. 38(33%) patients received adjuvant chemotherapy. After exclusion of postoperative mortality, the highest median survival was observed in the N1a (1228 days) and N2a1 group (992), the lowest in N2b (692), albeit not statistically significant. Kaplan-Meier curves are shown in figure 1. No significant survival difference was observed between N0-N1 and N2. Station 7 involvement was present in 21(19%) patients and was not a predictive factor. Conclusions No statistically significant survival difference was observed irrespective of nodal status. A trend was detected in favour of single-station N2a1 disease and against multi-station N2b involvement. When pneumonectomy is required, nodal disease does not seem therefore to prejudice survival in a carefully selected patient population. This is particularly important in the current clinical scenario where the range of multimodality options is on the increase.