69P Adjuvant Postmastectomy Hypofractionated Radiotherapy in Egyptian Cancer Patients, a 2 Years Follow-up

Abstract

AimThe use of conventional fractionation has been the standard practice for adjuvant postmastectomy radiotherapy in Egypt. Results of START A and START B Trials motivated us to investigate the use of 40 Gy in 15 fractions in adjuvant post-mastectomy radiotherapy and to document acute and 2-year late toxicity. Materials and methods235 women who underwent modified radical mastectomy for treatment of invasive breast cancer were randomized either to receive 50 Gy, in 25 fractions (122 patients, group A) or 40 Gy, in 15 fractions (113 patients, group B). ResultsThe patients’ and disease characteristics were comparable in both groups. Acute Skin toxicity occurred in 9 patients (7.37%) in group A (7 with grade 2 and 2 with grade 3), and in 7 cases (6.2%) in group B, 6 cases had grade 2 toxicity and 1 case had grade 3. None of the patients in both groups had grade 4 toxicities. Late skin toxicity occurred in 1 patient (0.8%) in group A and was of grade 2. Radiation pneumonitis occurred in 7 cases (5.73 %) in group A, and in 5 cases (4.42%) in group B and all were grade 1-2. One case in group A developed grade 3 left ventricular systolic dysfunction. Lymphedema occurred in 3 cases (2.45 %) in group A, 2 cases were of grade 1-2 and 1 patient had grade 3. While in group B, lymphedema occurred in 2 cases (1.76 %), 1 case had grade 3 lymphedema and 1 patient had grade 1-2. Acute and late toxicities were comparable in both groups. Relapse occurred in 43 cases (18.29 %), 24 cases (19.6%) in group A, among them, 2 cases had local recurrence, and 1 case had local and systemic relapse, the rest had systemic relapse. Relapse occurred in 19 patients (16.8%) in group B, 7 cases had systemic relapse, and 1 had local and systemic relapse. One case in group A (0.8%) developed contralateral breast cancer and One died because of breast cancer recurrence. There was no statistically significant difference among the two groups regarding local control or disease free and overall survival. The treatment interruptions, cost of treatment and work-load were lower in group B. ConclusionsHypofractionated postmastectomy radiotherapy offers local control and adverse effects comparable to the conventional fractionation with the advantage of reducing work load and cost of treatment. DisclosureAll authors have declared no conflicts of interest.