Opportunistic Biopsy of Internal Mammary Lymph Nodes During Immediate Breast Reconstruction After Mastectomy for Breast Malignancies.

Abstract

This study was designed to explore the clinicopathological factors associated with internal mammary lymph node (IMN) metastasis in radiologically IMN-negative breast malignancies and to discuss the clinical value of opportunistic biopsy during immediate breast reconstruction using free flaps, where the internal mammary vessels are the recipient. We retrospectively reviewed patients who received curative total mastectomy for breast malignancy followed by immediate reconstruction using transverse rectus abdominis myocutaneous (TRAM) free flap. Suspicious lymph nodes encountered during dissection of the third intercostal space for the recipient vessels were biopsied. Clinicopathological variables and the clinical impact associated with IMN metastasis were analyzed. Among 269 patients who underwent immediate reconstruction using a TRAM free flap, suspicious lymph nodes were identified and biopsied in 54 (20.1%) patients, and IMN metastasis was confirmed in 12 (22.2%) of these (4.5% of all reconstructions). Five patients were positive despite negative axillary lymph nodes and 11 underwent therapeutic plan modifications. Multivariate analysis revealed that IMN metastasis was independently associated with medial tumor location, invasive tumor >2 cm, and positive human epidermal growth factor receptor-2 status (P < 0.05). Aggressive IMN evaluation and biopsy in a subset of patients during immediate breast reconstruction using a TRAM free flap provided an additional opportunity for accurate breast cancer staging and appropriate adjuvant treatment, while minimizing unnecessary complications.