Evaluation of the impact of breast-conserving surgery on cancer outcomes of multiple (multifocal or multicentric) ipsilateral breast cancer

Breast conservative therapy (BCT) includes conservative breast surgery (CBS) with adjuvant radiotherapy and is now considered a standard treatment for early-stage breast cancer to achieve survival with acceptable aesthetic outcomes. Management of multiple ipsilateral breast cancer (MIBC) is a challenge, since the choice of optimal surgical procedures is controversial. Recently, many breast surgeons have advocated CBS is technically feasible to safely excise MIBC in selected cases. This study aimed to evaluate the outcome of MIBC patients who received CBS with special attention on local control and recurrence. This retrospective study was carried out on 90 patients at Al Azhar University Hospital and Ain Shams University Hospitals between January 2021 and January 2023. The majority of patients 85 (94.4%) had two foci of disease while five (5.5%) patients had three foci. The distance between the lesions ranges between 0.5 and 6.5 cm. The most common type of CBS was wide local excision en bloc resection of all lesions with normal tissue in between was done in 85 (94.4%) patients and five (5.5%) patients had two separate incisions leaving normal tissue in between. Clear margins were reported in 79 (87.7%) patients. 15 (5.5%) patients had different pathological lesion types (heterogeneous). One patient had a recurrence and another had distant metastases. With good patient selection, there is no difference between CBS and mastectomy in the management of MIBC. CBS is oncological safe provided that an adequate excision with clear margins followed by whole-breast radiation therapy and adjuvant systemic therapy.