GPPO2: PEDICULATED LATERAL THORACIC FLAP AS VOLUME REPLACEMENT IN BREAST CONSERVATIVE SURGERY

INTRODUCTION Breast cancer is the most common neoplasm and the leading cause of cancer death in women. Breast conserving surgery (BCS) is one of the two options for the surgical treatment of this disease. Breast reconstruction with local flaps is a tool for tissue replacement in BCS, where the defect is variable and depends on the anatomy and tumor situation. The lateral thoracic flap is based on a perforating intercostal vascular pedicle, it offers the option of tissue substitution when the defect is greater than 20% of the volume of the mammary gland. OBJECTIVE Describe the results of a volume substitution technique in BCS with a local pedicled flap because in our environment there is no bibliography about this type of procedure. MATERIAL AND METHODS Descriptive, observational, retrospective, cross-sectional study of cases obtained from the data base of the OncoMama clinic of the Hospital Regional de Alta Especialidad Materno Infantil de Nuevo León, we included patients diagnosed with breast cancer, operated on with BCS and pedicle flap. We briefly describe the surgical technique used in the lateral thoracic flap: -Pattern design. The pattern area in a 1:1 ratio of the resection area and the donor area. -Incision on the drawing of the pattern. Dissection and resection of the tumor with the usual technique with free margins. -Sentinel lymph node dissection or axillary lymphadenectomy: According to international guidelines on breast cancer treatment. -Dissection of the flap with visual localization and preservation of the lateral intercostal vascular pedicle. -Mobilization towards breast defect and fixation with absorbable suture. -Placement of drainage towards donor area and armpit. Primary closure of donor area. The variables to be described were age, BMI, tumor location, surgical time, histological type, clinical stage, post-surgical complications, resection margins, total resected volume, and cosmetic result. RESULTS 25 patients operated on in the period January 2020-June 2022 were included. The most common location is the upper outer quadrant. The smallest tumor size was 18 mm and the largest was 90 mm. The smallest resected volume was 6x6x4 cm and the largest 10x8.5x6 cm. There were no complications that required invasive intervention. The most common histology was non-specific type invasive carcinoma. The tumor margin in all cases was negative and the aesthetic result was satisfactory. DISCUSSION The treatment of breast cancer has evolved, achieving survival rates greater than 20 years, therefore, in addition to offering satisfactory oncological results, the objective of a better quality of life is added, including the aesthetic issue. The first local thoracolateral dermal-fat flap was described by Holmstrom and Lossing, however it was performed after mastectomy in a second surgical time. Munhoz AM et al, who described the thoracolateral flap in breast reconstruction. In our environment there is no bibliography about this type of procedure, so we describe the experience with this technique at the Hospital Regional Materno Infantil de Nuevo León with brief details of our surgical technique used. The shortcomings of this study are that it is retrospective, the number of cases is low, and the longest long-term follow-up is for 7 cases for 12 to 15 months. However, the short-term results are similar to the rest of the procedures in BCS, so we consider that this technique does not compromise survival or long-term oncological results. CONCLUSION We present this breast replacement reconstruction technique as an alternative in the range of options for BCS with oncological and cosmetic results comparable to other techniques, with the advantage of offering satisfactory substitution for extensive resections of the breast volume.