Influence of Comorbidities on the Efficacy of Radiotherapy with or without Chemotherapy in Elderly Stage III Non-small Cell Lung Cancer Patients

PURPOSE: The current study was conducted in order to evaluate the clinical outcome of radical radiotherapy (RT) with or without chemotherapy for elderly patients with stage III non-small cell lung cancer (NSCLC). MATERIALS AND METHODS: Between 1990 and 2010, 125 patients, aged 70 years or more, received radical RT with or without chemotherapy for treatment of stage III NSCLC. We reviewed the patients' prognostic factors, including comorbidities. Comorbidity status was evaluated using a simplified comorbidity score (SCS). Of the patients reviewed, 82 received radical RT alone, whereas the other 43 patients underwent chemoradiotherapy (CRT). A platinum-based chemotherapy regimen was most commonly used (42/43). RESULTS: The two-year overall-survival (OS) and progression-free survival (PFS) rates were 32.2% and 21.8%, respectively. SCS was the independent prognostic factor for OS. In the frail elderly subgroup with a SCS of ≥10, CRT demonstrated a significant difference in PFS, but not in OS. In contrast, OS and PFS following CRT were significantly superior to RT in the fit elderly subgroup with a SCS of <10. The incidence of severe pulmonary toxicities in the frail elderly subgroup was significantly higher than that in the fit elderly subgroup. CONCLUSION: Multiple comorbidities evaluated according to the SCS are related to poor OS in elderly patients with stage III NSCLC. CRT improved clinical outcome when compared to RT in the fit elderly subgroup, however, the gain from this treatment was negated in the frail elderly subgroup with multiple comorbidities. Therefore, evaluation of comorbidity is necessary in order to determine whether chemotherapy should be combined with RT in elderly patients with stage III NSCLC.