Abstract

Dr. Aravindh Sivanandan Anand M. D.* and Dr. Rose Maria John M. D.

ABSTRACT

Background: Low alpha by beta value of breast cancer provides a radiobiological rationale for radiation treatment in breast cancer. Randomized control trials and meta-analyses has proved beyond doubt comparable efficacy and toxicity for hypo fractionation after breast conservation surgery. But the evidence is limited after post mastectomy. Objective: The objective of this retrospective study is to assess the control rate of disease and toxicity after hypofractionated radiation and compare with the conventional fractionation. Methods: It was a retrospective study of all consecutive patients who received either conventional 50 Gy/25 fraction (Arm A) or 42.5Gy/16fraction (Arm B) as adjuvant post mastectomy radiation to chest wall +/- drainage areas. The departmental patient database were used for the study purpose and prepared proforma used for entering the relevant patient and treatment details. Results: A total of 109 patients were enrolled for the study, with 23 patients in Arm A and 86 patients in Arm B. The median follow up period was 56 months. The local recurrence rate was 8.7% in arm A while it was 11.6% in Arm B (p= 1.000). Overall recurrence was 26.1% & 31.4. % respectively (P=0.623). The mean overall survival 59.3% and 53.9% (p =.098) respectively. 4 year O.S was 91.3% & 74.4% respectively (p=0.0838). 4 year DFS was 77.7% & 67.6% respectively (p=0.3512). Toxicities in both arms were comparable Conclusion: In breast cancer post mastectomy hypofractionated radiation treatment is a viable & scientifically proved option with reduced patient burden and comparable toxicity to conventional fractionation.