Disección axilar dirigida tras tratamiento sistémico primario en cáncer de mama N1. Validación de la técnica y experiencia a los 4 años

Objectives

To assess the omission of systematic axillary lymphadenectomy (ALND) in patients with N1 breast cancer with axillary pathological response (APR) after primary systemic treatment (PST). Description and experience of the Technique: Target Axillary Dissection TAD. Identify which subtypes are associated with higher APR.

Patients and methods

A descriptive, retrospective study of 90 patients with cT1-T3/N1/M0 stage breast carcinoma who received TSP at the Valencian Institute of Oncology (IVO), between January 2020 and December 2023; 63 received chemotherapy and/or anti-HER2 therapy and 27 received hormonal therapy. Biopsy and labeling of the suspicious lymph node (maximum 3) were performed. In the surgery, a harpoon was placed in the axillary lymph node and the sentinel lymph node (BSGC) technique was also performed with technetium-99m and methylene blue.

Results

APR was achieved in 46/90 cases (51.2%), in 30/46 (65.2%) pCR, and in 16/46 ITC (isolated tumor cells) or micrometastases remained. Macrometastases were observed in 44/90 (48.8%) and therefore ALND or axillary Rt was performed. There have been no axillary or distant relapses. Detection of the marked node: 100%. RPA occurred in: Luminal A, 26%; Luminal B, 42%; HER2-positive, 86% and Triple Negative, 66%.

Conclusions

In the IVO, ADT is a feasible technique. More than 50% of the cohort had an APR avoiding ALND. The HER2-positive and triple negative subtypes have the highest response rate. It is an oncologically safe procedure; NOT less than ALND.