Control of resection margins after neoadjuvant systemic therapy in breast-conserving surgery in breast cancer patients

BACKGROUND: Surgical treatment of breast cancer plays a major role in the combined and complex treatment of patients. The purity of the examined edges of the resected breast tissue is the main indicator of the reliability of the breast-conserving surgery and one of the main factors in the development of local recurrence. Neoadjuvant (preoperative) systemic therapy allows evaluating the effectiveness of therapy in vivo and reducing the size of the initial formation, both in locally advanced and resectable forms of breast cancer. The main advantage of this treatment is the ability for surgeons to perform breast-conserving surgery to improve patients quality of life and aesthetic outcomes without compromising disease-free and overall survival. AIM: To study the clinical and pathological characteristics and analyze of the breast-conserving surgery in patients with breast cancer after neoadjuvant chemotherapy. MATERIALS AND METHODS: 156 performed breast-conserving surgery after neoadjuvant chemotherapy were analyzed. Breast-conserving resection implied radical removal of the residual tumor node within healthy breast tissues with the achievement of negative resection margins. If pathologists detected stained invasive cells/cancer in situ in a formalin-fixed preparation, a second surgical intervention was performed. RESULTS: Of the 156 studied anatomical preparations after breast-conserving surgery, a positive margin was found in 4 (2.56%) cases. In 4 patients, positive margin was represented by ductal carcinoma in situ. According to the results of trephine biopsy, no intraductal component was found before neoadjuvant chemotherapy. The greatest length of the ductal carcinoma in situ section is 2.2 mm. In 3 cases, the distance to the stained resection margin of the micropreparation was 1 mm. As a result of repeated pathomorphological examination of pre-cut margins after surgical intervention, cancer in situ was not found. CONCLUSIONS: The ongoing neoadjuvant systemic therapy for breast cancer with a partial or complete response of the tumor increases the percentage of breast-conserving surgery performed in patients who initially belong to the group of radical mastectomy, but who want to save breast tissue.