ESTRO meets Asia 2024 - Abstract Book

S86

Interdisciplinary – Breast

ESTRO meets Asia

346

Digital Poster

Current practice pattern of postmastectomy hypofractionated radiotherapy: A revolution in management

Nowshin Taslima Hossain 1 , Qazi Mushtaq Hussain 2 , Altaf Hossain Riad 3 , Aditi Paul Chowdhury 1 , Jannatul Ferdause 1 , Rubama Karim 1 1 Radiation Oncology, AMCGH, Dhaka, Bangladesh. 2 Radiation Oncology, Labaid Cancer Hospital And Super Speciality Center, Dhaka, Bangladesh. 3 Radiation Oncology, KMCH, Khulna, Bangladesh

Purpose/Objective:

Radiation fractionation schemes have been modified from conventional to hypofractionated schedules in management of breast cancer both in whole breast and chest wall irradiation. This study aimed to investigate the feasibility and consequences of hypofractionated irradiation in post-mastectomy chestwall and regional nodes in a tertiary cancer care hospital in Bangladesh.

Material/Methods:

This study was a retrospective review of a prospectively maintained database from Ahsania Mission Cancer & General Hospital of Bangladesh. From March 2017 to February 2024, 39 women aged ≥30 years with stages II or III (pT 1 , pT 2 , pT 3 , pT 4 and node positive) breast cancer who had treated with mastectomy, chemotherapy (8 cycles AC-T or 6 Cycles FAC schedule) followed by hypofractionated radiotherapy to chest wall and regional nodes (4256cGy in 16 fractions, 2.66Gy per fractions, one fraction per day , five fractions per week completed over 3 weeks) were selected. Primary endpoint was 10 years overall survival. Here we represent only the median disease free survival. Patients with bilateral breast cancer, recurrent disease and those who did not receive radiation were excluded. From March 2017 to February 2024, among 39 breast cancer patients, mostly diagnosed as premenopausal (61.5%) with a median age of 45 years (range 30 to 70 years). Notable risk factors were positive family history, OCP use and passive smoking . Most Common histological subtype was Infiltrating ductal carcinoma (92.2%). Mostly grade II (37.3%) and LVSI was detected in 27.5% cases. Luminal A that is ER +ve; PR +ve; HER2 -ve; Ki67 low (35.3%) and TNBC (24%) contributed more. Chemotherapy was received by all the patients. Only 15.7% patients received Neo-adjuvant chemotherapy. Sandard protocol was 4 cycles AC (Doxorubicin, Cyclophosphamide) followed by 4 cycles Taxane (60.8%). All patients underwent mastectomy with axillary lymph node dissection and received hypofractionated radiotherapy: 4256 cGy in 16 fractions. No patients experienced grade 3 or higher radiation toxicities. 7 out of 39 patients experienced recurrence (17.9%). Estimated median disease free survival was 40 months (95% CI, 23.12-58.86). Results:

Conclusion:

Considering the median disease free survival and low acute toxicities, moderate hypofractionated radiotherapy is now widely used in diverse patient population of breast cancer in Bangladesh. Continued research will go on to see the overall survival results.