Hypofractionated Radiotherapy Versus Conventional Radiotherapy in Post-operative Breast Cancer: A Comparative Study on Acute Toxicity and Doses to Organs at Risk in Bangladesh

Background Breast cancer is considered a systemic disease, demanding multimodalities of treatment like surgery, radiation therapy, chemotherapy, hormone therapy, etc. Adjuvant radiotherapy significantly improves locoregional control. This study was aimed at comparing the acute toxicities and doses to organs at risk of hypofractionated radiotherapy versus conventional radiotherapy in post-operative breast cancer in Bangladesh. Methods This comparative study was conducted from April 2023 to March 2024 on 70 patients with post-operative breast cancer for whom radiotherapy was indicated. Patients were divided evenly between the two arms. Patients in arm A received hypofractionated radiotherapy (40 Gy in 15 daily fractions, 2.67 Gy per fraction), while those in arm B got conventional radiotherapy (50 Gy in 25 daily fractions, 2 Gy per fraction). Each patient was evaluated before, during, and after the completion of the treatment. Results Radiation-induced dermatitis (p = 0.01) and fatigue (p = 0.03) were significantly less in the hypofractionated arm in comparison with the conventional radiotherapy arm. Other toxicities like radiation-induced pneumonitis, esophagitis, and lymphedema were similar in both arms. Doses in the organs at risk were almost similar in both arms except for the mean dose to the ipsilateral lung (p = 0.02) and thyroid gland (p = 0.01), which were statistically significant. Conclusion Hypofractionated radiotherapy causes less acute toxicities like radiation-induced dermatitis and fatigue with similar doses in organs at risk in comparison to conventional radiotherapy in post-operative breast cancer.