Recent trends in use of adjuvant chemotherapy in elderly stage II–III non-small cell lung cancer

BACKGROUND: Although randomized trials demonstrated survival benefit of adjuvant chemotherapy, previous reports have suggested that its use in elderly populations for early stage non-small cell lung cancer (NSCLC) was infrequent. The current status of adjuvant chemotherapy in this population is unknown. METHODS: Using the Surveillance, Epidemiology, and End Results (SEER) database, we examined the incidence of chemotherapy in resected stage II–III NSCLC between 2004 and 2015. Staging was determined according to the American Joint Committee on Cancer (AJCC) 6th version. Cases were grouped by age (20–69, 70–79, and 80+). Trends in use of chemotherapy by age group were assessed by univariate and multivariate analyses. RESULTS: A total of 35,009 cases were selected as surgically resected stage II–III NSCLC. Use of chemotherapy was 66.9%, 48.2%, 25.0% in age 20–69, 70–79, 80+, respectively. Multivariate analysis demonstrated that younger age [20–69] and recent year [2010–2015] of diagnosis were associated with increased use of chemotherapy. Chemotherapy use increased from 2004 to 2015 by 11.0%, 18.3%, and 11.3% in age 20–69, 70–79, 80+, respectively. In the age 70–79 group, increased use of chemotherapy was greater in stage II (24.3%) than stage III (14.1%). Five-year overall survival in age 70–79 group mildly increased by 7.6% from 2004 to 2011. CONCLUSIONS: This study suggests that use of adjuvant chemotherapy in the elderly population increased primarily in age 70–79. Few patients in the 80+ age group received adjuvant chemotherapy even in recent years.