DEFINITIVE CHEMORADIOTHERAPY AND SURVIVAL OF PATIENTS WITH ANAL CARCINOMA: A POPULATIONAL COHORT STUDY

Background: Anal cancer carcinoma (AC) is an uncommon illness with scarce evidence from low and middle-income nations. We performed a cohort study in a cancer database to evaluate the treatment outcomes of AC treated by chemoradiotherapy (CRT). Methods: Patients with AC staged I-III diagnosed from 1999 to 2020 and treated by CRT were identified from The Fundação Oncocentro de São Paulo database. Tumor category (T), Nodal category (N), age, gender, education level, practice setting, time to radiotherapy, histology, and treatment local data were extracted. The Cox proportional hazard model used the hazard ratio and 95% CI to evaluate the overall survival (OS) and cancer-specific survival (CSS) rates and the relationship with tumor and patient factors. Results: With a median follow-up of 72 months, 1462 patients were evaluated. The five and 10-year OS rates were 61% and 46%, respectively. In addition, the five and 10-year CSS rates were 67% and 60%. T category, N category, gender, practice setting, and educational level were associated with OS and CSS in the univariate analysis, p<0.05. In the multivariate analysis, T1/2 category (p=0.001), N0 category (p=0.0001), female (p=0.0001), and private service (p=0.001) were independently associated with OS. For CSS, T1/2 category, N0 category, female, and private service remained significant, p<0.05. Conclusion: CRT produced satisfactory five and 10-year OS and CSS rates in this cohort analysis with 1462 AC patients. However, tumor and patient factors influenced the outcomes. We hope these data could help to improve the outcomes of AC patients submitted to CRT.