Selection of postoperative adjuvant therapy for patients with stage IB lung adenocarcinoma: analysis of 653 cases

Abstract

To explore the optimal postoperative adjuvant regimens for patients with stage IB lung adenocarcinoma. We respectively analyzed the data of 653 patients undergoing surgery for stage IB lung adenocarcinoma in our hospital from January, 2013 to December, 2021. The 5-year disease-free survival (DFS) and overall survival (OS) rates were compared among the patients receiving postoperative adjuvant therapy with epidermal growth factor-tyrosine kinase inhibitors (EGFR-TKIs group, n=111), chemotherapy (CT group, n=108) and clinical observation (CO group, n=434). In TKIs, CT, and CO groups, the 5-year DFS rates were 92.8%, 80.7%, and 81.7%, respectively, significantly higher in TKIs group than in CO group (P < 0.01). The 3-year OS rates of the 3 groups were 96.8%, 97.1%, and 91.7%, respectively. Subgroup analysis showed that in TKIs, CT, and CO groups, the 5-year DFS rates of patients with with T3-4 cmN0M0 were 92.6%, 84.0%, and 81.4%, respectively, significantly higher in TKIs group than in CO group (P < 0.05); the 5-year DFS rates of T2ViscPlN0M0 patients were 95.1%, 71.4%, and 83.5%, respectively. Multivariate COX regression analysis showed that age (P < 0.05; HR=0.631, 95% CI: 0.401-0.993), solid nodules (P < 0.01; HR=7.620, 95% CI: 3.037-19.121), micropapillary or solid component (P < 0.05; HR= 1.776, 95% CI: 1.010-3.122), lymphovascular invasion (P < 0.05; HR=2.981, 95% CI: 1.198-7.419), and adjuvant therapy (P < 0.01) were independent predictors of DFS. The most common adverse effects included rashes, paronychia, and diarrhea for TKIs and hematological suppression and gastrointestinal reactions for chemotherapy, and TKIs were associated with a higher incidence of grade 3 or above adverse effects (44.4% vs 9.0%). Adjuvant therapy with TKIs helps improve DFS in patients with stage IB (T3-4cmN0M0) lung adenocarcinoma but not in patients with T2ViscPlN0M0. Adjuvant chemotherapy does not improve DFS or OS in patients with stage IB lung adenocarcinoma.