Clinical characteristics and prognosis of elderly patients with anal cancer

Abstract Purpose. The clinical characteristicsand prognosis of anal cancer in the elderly have not received sufficient attention. The study aimed to evaluate the clinical features and prognostic factors of elderly patients with anal cancer. Method . The characteristics of anal cancer patients (aged <65 and ≥65) diagnosed during 2004-2017 were collected from the Surveillance, Epidemiology, and End Results (SEER) database. Propensity score matching (PSM) was used to correct age bias caused by assessed confounders. The chi-squared (χ2) test was used to assess differences in categorical variables of characteristics between two age groups., The Kaplan-Meier survival technique, Log-rank test, Cox regression, and nomogram were used for survival analysis. Results . The receipt of adjuvant age increases the risk of overall survival by 86% after propensity-score matching (HR=1.86, 95%CI=1.70-2.03,P<0.001). Compared with the younger population, the elderly accounted for a higher proportion of unmarried statuses and adenocarcinomas. COX regression analysis shows older age, non-squamous cell carcinoma, unmarried status, and advanced AJCC stage as independent risk prognostic factors for anal cancer in the elderly. The effects of chemotherapy, radiotherapy, and surgery all improved the prognosis of the elderly. Besides, senior score and survival probability could be accomplished by our nomogram with a c-index of 0.7179. Conclusion . Relatively low rates of chemoradiation and relatively conservative therapy regimens are associated with a poorer prognosis in elderly anal cancer. At the same time, surgery has a potential role in improving the prognosis of elderly anal cancer patients.