Efficacy of postoperative radiotherapy and prognosis in patients with completely resected stage Ⅲ(pN 2) lung adenocarcinoma with EGFR wild-type receiving adjuvant chemotherapy / 中华放射肿瘤学杂志

ABSTRACT

Objective:To evaluate the value and identify the prognosic factors of postoperative radiotherapy (PORT) in completely resected stage Ⅲ(pN 2) lung adenocarcinoma patients with epidermal growth factor receptor (EGFR) wild-type who received adjuvant chemotherapy. Methods:Clinical data of 172 patients with stage Ⅲ(pN 2) EGFR wild-type lung adenocarcinoma who underwent radical resection and adjuvant chemotherapy from 2009 to 2016 were retrospectively analyzed. All patients received platinum-based adjuvant chemotherapy combining two drugs for>4 cycles, and divided into the PORT group and the non-PORT group. The survival rate was calculated by Kaplan- Meier method and log-rank test, and multivariate prognostic analysis was performed by Cox’s regression model. Results:Among 172 patients, the median overall survival (OS), 3-year and 5-year OS rates were 40 months, 55.9% and 28.3%, respectively. The median disease-free survival (DFS), 3-year and 5-year DFS rates were 17 months, 24.5% and 13.0%, respectively. DFS was significantly improved in the PORT group (29 months vs. 13 months, P=0.001), whereas OS did not significantly differ between two groups (51 months vs. 38 months, P=0.151). In subgroup analysis, DFS of patients with multistation N 2 or the number of N 2 metastases of≥3 or skip N 2 in the PORT group was significantly longer ( P<0.05), whereas PORT exerted no significant effect on OS ( P>0.05). Conclusions:For patients with completely resected stage Ⅲ(N 2) EGFR wild-type lung adenocarcinoma receiving adjuvant chemotherapy, PORT might increase DFS and have a trend toward longer OS. However, these findings remain to be validated by large sample size investigations.