Impact of comorbidity on tolerability and survival following curative intent intensity modulated radiotherapy in older patients with nasopharyngeal cancer.

Abstract

This study aimed to evaluate the predictive factors for survival and acute toxicities in older patients with NPC treated with curative intent IMRT. Older patients aged 65 years and above with non-metastatic NPC treated with curative intent IMRT between 2003 and 2013 were retrospectively analysed. Variables examined were gender, age, overall stage, chemotherapy use, Eastern Cooperative Oncology Group (ECOG) performance status and comorbidity. The comorbidity severity was determined by adult comorbidity evaluation (ACE-27). We considered hospitalization or placement of feeding tube during and up to one month post radiotherapy as surrogate endpoint for significant acute toxicities. Other endpoints examined were: OS (overall survival), DFS (disease free survival), DSS (disease specific survival). A total of 185 patients were eligible for analysis. Median age was 70 (65-86 years). Most of the patients presented with Stage III and IVA/B (n = 127, 68.7%), of good performance status of ECOG 0-1 (n = 176, 95.1%) and had low comorbidities with ACE-27 score of 0-1 (n = 141, 76.2%). Chemotherapy was delivered to 84 patients (45.4%). OS, DFS, and DSS were 64.5%, 51.4%, and 72.8% respectively. High comorbidity burden but not chemotherapy had significant impact on OS and DFS in patients with advanced stage. Fifty patients (27%) required tube feeding or hospitalization during the course of RT. Males, chemotherapy use and ECOG score ≥2 were significant predictors of tube feeding or hospitalization during RT. Curative IMRT was associated with excellent survival outcomes in older patients with NPC. Comorbidity but not chemotherapy was associated with prognosis in advanced stage. Careful monitoring and intensive support should be instituted in older males with ECOG score ≥2 receiving chemo-radiotherapy.