Impact of Surgically and Radiologically Detected Incidental Internal Mammary Lymph Node Enlargement in Breast Cancer Patients Undergoing Free-Flap Breast Reconstruction

Abstract

Abstract Background The internal mammary lymph node (IMLN) basin is considered the second most important regional nodal basin in breast cancer. IMLNs are often not detected radiologically and left untreated, with symptomatic recurrence being 0.1%. Challenges in accessibility have been an obstacle in achieving a comprehensive treatment plan, especially with undetermined and radiologically enlarged IMLN. Free autologous tissue breast reconstruction is considered the gold standard, and the familiarity of microvascular surgeons in using the internal mammary vessels (IMVs) puts them in a unique position to shed more light on the natural pathological process of IMLN metastases. Materials and Methods A retrospective data analysis study was conducted evaluating 270 patients who underwent 307 free flaps for breast reconstruction using the IMV in the period between 2009 and 2017. Patient's demographics and clinicopathological data including IMLN harvest, radiological, operative details, adjuvant therapy, postoperative morbidity, and follow-up outcome data were analyzed. Results Eighty-nine enlarged IMLNs were surgically retrieved from 30.7% (83/270) of the patients (73 delayed, 10 immediate breast reconstructions) with an age range of 29 to 77 years (mean: 45). Eighty six were incidentally encountered during surgery, whereas in three, the enlarged IMLN was preoperatively, radiologically determined and biopsied during computed tomography (CT) scan staging and was retrieved subsequently during surgery. IMLN metastases were confirmed in 8.4% (7/83) of the patients in whom IMLNs were retrieved with subsequent modification of the proposed adjuvant therapy. The follow-up period ranged from 3 to 84 months (mean: 42) for the involved IMLN patients. Two patients (28% [2/7]) showed signs of disease progression with mortality. Conclusion Microvascular surgeons in a multidisciplinary setting would provide a valuable role in improving outcomes of patients with IMLN metastases through better diagnosis and staging of incidentally enlarged metastatic IMLN and provision of an effective approach for locoregional disease control.