Abstract
Background: Post-mastectomy radiotherapy reduces loco-regional recurrence in women with operable breast cancer and improves survival. Conventional fractionated radiotherapy has been limited by patient’s compliance, travelling, unplanned interruption and others. Hypofractionated schedule would be more appealing and convenient. The present study was carried out to compare overall survival, disease free survival, loco regional control, and treatment toxicities, in patients treated with conventional fractionated radiotherapy and hypofractionated schedules. Methods: Forty-seven patients with breast cancer (stage T2-4, any N), underwent surgery and received adjuvant systemic treatment and radiotherapy. These patients randomly divided into two groups; conventional fractionated radiotherapy group (N: 22), and hypofractionated radiotherapy group (N: 25). Data of radiation toxicities, and disease relapse in both groups were compared using Chi-square test. Results: The median follow-up was 34 months (range: 13 – 53 months). Four-year overall survival rates were 100% for conventional radiotherapy group and 96% for hypofractionated radiotherapy group, with no significant difference (P value= 0.37). The 4 year disease free survival rate were 81% and 92% for conventional radiotherapy group and hypofractionation radiotherapy group, respectively (p-value= 0.47) and hazard ratio= 0.52 (0.09-2.13). Toxicities were comparable between the both groups. Conclusions: these data showed that hypofractionation 42 Gy radiotherapy in 16 fractions was safe and comparable to conventional fractionation in terms of overall survival, loco-regional tumor control and toxicities. These results need to be tested in large-scale multicenter randomized control trials.

