Single-incision for breast-conserving surgery through round block technique

Aims and objectives: The purpose of this study was to assess the feasibility of using the single-incision round block technique in breast-conserving surgery with sentinel lymph node (SLN) retrieval for breast cancer without compromising oncological safety. Materials and methods: A retrospective observational case-control study was conducted from January 2017 to October 2021. The study population consisted of two groups. In both groups, breast-conserving surgery was carried out through the round-block technique. In group A, SLN retrieval was performed using the round-block incision (study group), while in group B, SLN retrieval was conducted through a second skin incision in the axilla (control group). The study was approved by the local ethics committee Zurich (BASEC-Nr. 2020-02857), and written informed consent was obtained from all participants. Results: Overall, 134 patients met the inclusion criteria, of whom 86 women underwent breast-conserving surgery and SLN retrieval using the single-incision approach (group A), and 48 women underwent conventional surgery, using two independent incisions for tumour resection and SLN retrieval (group B). The overall success rate in group A regarding SLN retrieval was 97.7%, whereas most tumours were located in the upper outer (47.7%) and upper inner quadrant (27.9%). Although the technique was equally successful in the other quadrants, the share of tumours in the lower outer, and the lower inner quadrant, and the retroareolar region was smaller, representing 17.4%, 3.5% and 3.5%, respectively. The median number of dissected lymph nodes was two, with a positivity rate of 24.4%. The occurrence of axillary neuralgia and axillary skin retraction was significantly higher in group B along with tendentially more axillary seroma formation. There were no significant differences regarding reintervention rates, in terms of complications, resection margins, locoregional recurrences, or deaths with a mean follow-up of 11 months. Conclusio