The impact of Adult Comorbidity Evaluation-27 on the clinical outcome of elderly nasopharyngeal carcinoma patients treated with chemoradiotherapy or radiotherapy: a matched cohort analysis

Objectives: To evaluate the prognostic significance of Adult Comorbidity Evaluation-27 (ACE-27) for elderly patients (age ≥70 years) with locoregionally advanced nasopharyngeal carcinoma (NPC) treated with Intensity-Modulated Radiotherapy (IMRT), with or without chemotherapy.Methods: 206 elderly patients with locoregionally advanced NPC treated from December 2006 to December 2016 were involved into analysis as the training cohort.Besides, a separate cohort of 72 patients from the same cancer center collected between January 2003 and October 2006 served as the validation cohort.By using propensity score matching (PSM), we created a balanced cohort by matching patients who received chemoradiotherapy with patients who received IMRT alone.Treatment toxicities were calculated between CRT and RT groups using the χ 2 test.The primary endpoint was cancer-specific survival (CSS).Multivariate analysis was performed to assess the relative risk for each factor by using a Cox's proportional hazards regression model.Results: The median follow-up was 39.0 months (range = 3-137 months).In the PSM cohort, patients in the CRT group achieved comparable survival compared with patients in the RT group.The 3-year CSS rate was 64.3% and 65.2%, respectively (P =0.764).In multivariate analysis, the addition of chemotherapy to IMRT was not an independent prognostic factor for CSS, whereas a high ACE-27 score was an independent risk factor.In subgroup analysis with ACE-27 score ≥ 2, the 3-year CSS rate was worse in patients from the CRT group (63.5% vs. 46.3%,P = 0.041).Conclusions: CRT is comparable to IMRT alone for elderly patients with locoregionally advanced NPC.The ACE-27 tool may help to identify high-risk subgroup for poor disease outcome and tailor individualized treatment.