Management of Ectopic Breast Tissue

Abstract

In their article, Ectopic Breast Cancer: Case Report and Review of the Literature [1], the authors provide an overview of the incidence of ectopic breast tissue and current opinions on its management. They report on a case of ectopic breast tissue that harbored a malignancy, for which they performed a resection and subsequent reconstruction with a good outcome. Based on this case and their review of the literature, they recommend excision of all aberrant breast tissue. The Kajava classification of ectopic breast tissue as delineated in Ghosn et al. [2] is purely descriptive but may provide a starting ground for clinical management guidelines. The distinction between ectopic, supernumerary, and aberrant breast tissue can be simplified into clinically applicable categories. Because the authors conclude that this may have a bearing, from an oncologic standpoint, on patient management, it is important to clarify the definitions. Ectopic breast tissue includes all breast tissue not confined to the chest breast mounds. Supernumerary breast tissue is ectopic breast tissue not confined to the chest wall mounds but present along the mammary ridge (class 2 and 3 in the Kajava classification). Aberrant breast tissue is ectopic breast tissue not confined to the mammary ridge (class 4 in the Kajava classification). Recently, certain investigators have even suggested that the presence of supernumerary breast tissue is ubiquitous, which is demonstrable in patients with acquired immunodeficiency syndrome (AIDS) who undergo hypertrophy of these tissues [3]. In the reported case, supernumerary axillary breast tissue was incidentally found to contain a malignant tumor. However, in the ‘‘differential diagnosis’’ section of the discussion, this axillary tissue was denoted as aberrant. This incongruence underscores the importance of clarifying definitions before proposing interventional recommendations as the authors have in their article. Francone et al. [1] have concluded that all aberrant breast tissue should be prophylactically excised. The rationale they invoke is the hypothetical higher risk of malignant transformation, the potential late presentation, the psychological benefit of excision, and a more limited resection as a prophylactic procedure. However, likely due to the rarity of this condition, the handful of publications referenced to justify prophylactic excision are mostly case reports with reviews of the literature [2, 4–6], which commonly cite each other. In my opinion, the paucity of data on this matter does not allow for such definitive conclusions. Resection of all aberrant breast tissue, as the authors suggest, should be weighed against the potential risks of surgery, particularly given the lack of high-level evidence. Prophylactic excision of ectopic breast tissue prompts a comparison with prophylactic mastectomy, a highly investigated yet continuously controversial topic [7, 8]. Whether prophylactic mastectomy, except in very high-risk patients, justifies the surgical morbidity or not has not been clarified to date. Clearly, prophylactic mastectomy is more extensive surgery, and the overall risk-benefit balance may have factors of greater magnitude than those in the ectopic breast tissue scenario. Francone et al. [1] emphasize that in addition to the theoretical oncologic advantage, early, limited resection has J. Bank (&) University of Chicago Medical Center, 5841 South Maryland Avenue, Chicago, IL 60637, USA e-mail: jonathan.bank@uchospitals.edu