INTRODUCTION:
One of the goals of neoadjuvant therapy is to make the tumor volume-to-breast ratio suitable for breast-conserving surgery (BCS) by reducing the tumor size in patients with large tumors (1). Randomized controlled trials have shown that neoadjuvant therapy increases the rates of BCS and presented suggestions for performing BCS after neoadjuvant chemotherapy (NAC) in patients who are not suitable candidates for BCS at the time of presentation (2,3). The concepts of marking both the primary tumor and the metastatic axillary lymph node in the pre-NAC period, and targeted primary tumor and axillary surgery in the post-NAC period have been developed (4). Concepts regarding surgical margins in patients, who underwent breast surgery after NAC, have become clearer over time, and concerns on this issue have decreased (5,6). There is a consensus that with appropriate surgical intervention, local control can be achieved without mastectomy after NAC (7,8). The main point is to obtain adequate surgical margins with the accurate localization of the tumor.
It is known that BCS was not planned in a group of patients before NAC, therefore tumor marking was not performed, but BCS was thought after NAC (unplanned BCS). It is not possible to perform BCS due to tumor localization problems particularly in patients achieving good clinical response. In some cases, pre-NAC tumor marking cannot be performed due to technical issues. The literature review has shown that there are studies presenting the results obtained from unplanned BCS after NAC. Conventional BCS techniques were used in these studies. Furthermore, they are relatively old studies, and therefore, neoadjuvant therapy criteria for patients included in these studies are unclear (9,10). Oncoplastic surgery (OPS) is known to ensure larger tissue excision compared to the conventional BCS and provides the opportunity to obtain wider surgical margins (11). It can be advantageous in unplanned BCS. This study focused on the results obtained with planned and unplanned level II OPS techniques applied to patients after NAC.