Treatment options of breast cancer patients after breast-conserving surgery with positive margins R1

Introduction: in organ-preserving operations for breast cancer, the risk of recurrence is associated with many factors, including positive resection margins. The article presents data from the literature, which considers the risk of relapse depending on the positive, close and negative edges of resection. The purpose of this study was to increase the effectiveness of treatment of breast cancer patients after organ-preserving operations with positive resection edges. Materials and methods: the study included 1219 patients with breast cancer who underwent organ-preserving and oncoplastic resections of the breast. Urgent cytological and histological intraoperative examination of the resection edges is analyzed in detail, and the marking of the resection edges is presented. The clinical and morphological characteristics of patients with breast cancer at R0 and Rl are presented. Results: positive edge of Rl resection was diagnosed in 53 cases, which was 4,3±2,8%, in oncoplastic resections in 4,1±1,1%, in classical breast resections in 4,6±0,7% (p>0,05). In the group of patients with Rl, multicentricity of the tumor was diagnosed in 11,1±5,3%, and monocentric tumor was detected in 4,1 ±0,5%. Further tactics in the case of Rl detection were as follows: in 21 cases, radiation therapy was performed on the breast, in 32 cases, re - operation: resection of the edges - in 14 patients, radical mastectomy - in 9 patients, subcutaneous mastectomy with simultaneous reconstruction with autologous flaps or endoprostheses - in 9 patients. In the group of patients with re-operation, 43,7% of the planned study showed no signs of malignancy, 56,3% showed a residual tumor, while 31.3% were diagnosed with cancer in situ. So in the case of resection of the edges in 5 cases, a residual tumor was diagnosed in the resected edges, which was 35,7%, and in the case of mastectomy, a residual tumor was detected in 68,4%. Re-operation in R1 after oncoplastic resections was performed in 71,4%, and in classical resections in 56,4%, which correlates with the literature data. Conclusion: in two groups of patients after organ-preserving operations with positive resection margins, no local recurrence was detected during the follow-up period from 1 to 60 months, and distant metastases, namely, lesions of the bones of the skeleton, were diagnosed in 2 patients. Thus, with a positive edge of resection after organ-preserving surgery, both surgical treatment and radiation therapy can be performed. Although the presence of a tumor in the colored edges of resection is clearly associated with a high frequency of local relapses, but the relapse is also influenced by the biological characteristics of the tumor and the body. Individual characteristics are the basis of tumor biology, and the extent of their influence on long-term results is not reduced due to the wide surgical margins of resection. © 2020 Izdatel'stvo Meditsina. All rights reserved.