A retrospective analysis of concurrent chemoradiation for squamous cell carcinoma of the anus in Johannesburg

Background: Anal cancer is a major cause of mortality and morbidity in low- and middle-income countries (LMICs). Aim: A retrospective analysis to understand presentation and outcomes of patients with anal cancer, who were treated with a curative intent. Setting: A radiation oncology unit in quaternary level hospital in South Africa. Methods: Medical records of patients with invasive squamous cell carcinoma (SCC) of the anal canal who were treated between 2014 and 2019 were reviewed with follow-up until June 2021. The 2D-radiotherapy planning and delivery techniques were used to a dose of 50 Gy, with a boost dose of 6 Gy – 10 Gy for patients with residual disease and concurrent chemotherapy. Results: Eighty-four patients were included in the analysis. Median age was 45 years (range: 25–73 years), 75% were female patients, 80% of the cohort was human immunodeficiency virus (HIV)-positive, and 17% with a CD4 count below 200 cells/mm 3 . Eighty-seven percent had locally advanced stage three disease. Concurrent 5-fluorouracil (5-FU) and mitomycin C-based chemotherapy was given in four patients, while 50% had 5-FU plus cisplatin and 16% had radiotherapy alone. Complete clinical response was observed in 54 out of 66 evaluable patients (81.8%) at 6 months post-chemoradiation. Overall survival at 2 years could not be determined because of a significant loss to follow-up rate. Conclusion: A high HIV-postive rate and an advanced disease stage were observed among cohorts with anal canal SCC treated with a definitive curative intent. Tumour response rates at 6 months were favourable although the 2-year overall survival could not be established. Contribution: This study contributes to the growing body of research on anal cancer outcomes in LMICs.