Internal mammary node management in breast cancer. A review

Abstract

Background. Internal mammary nodes visualized during sentinel node biopsy for breast cancer, remain an unresolved management issue. Further, both internal mammary node (IMN) radiotherapy and biopsy have attendant risks and hence should be used with caution. The purpose of this review is to highlight the available data and evidence. Methods and Results. A PubMed database from 1960 to 2012 using key words: internal mammary nodes, breast cancer radiotherapy planning, adjuvant radiotherapy, sentinel node biopsy in breast cancer and selected publications on the significance of internal mammary nodes in breast cancer treatment, published data and approaches used. We found 14513 relevant papers and we selected 30 that clearly investigated the management of internal mammary nodes during sentinel node search. We focused on the incidence of IMN metastasis (6 papers), risk factors associated with IMN drainage (9 reports), management of IMN and the impact on disease free and overall patient survival (15 papers). Conclusions. The evidence for breast cancer axillary nodes management is good but the data for other draining nodes such as internal mammary nodes are far less conclusive and further research is needed.

Dosimetric Comparison of Volumetric Modulated Arc Therapy, Static Field Intensity Modulated Radiation Therapy, and 3D Conformal Planning for the Treatment of a Right-Sided Reconstructed Chest Wall and Regional Nodal Case

“…However due to treatment related morbidity issues and the lack of data that shed light on the impact of radiating the IMNs in isolation, the controversy on inclusion of the IMNs as part of the regional nodal irradiation still continues. It is therefore recommended to make the judicious choice of irradiating the IMNs in patients that require it provided one is able to administer treatment to this region while sparing normal surrounding tissues [1]. Hence, techniques other than conventional treatment planning may be needed to be explored for inclusion of IMNs in regional nodal radiation.…”

“…Radiation therapy of the internal mammary nodes (IMN) for the treatment of breast cancer is a controversial topic [1]. The MA20 trial from the National Cancer Institute of Canada has provided preliminary results suggesting that regional nodal irradiation reduces distant metastases as well as regional recurrence rates [2].…”

Prognostic Influence of Internal Mammary Node Drainage in Patients with Early-stage Breast Cancer

“…Imaging studies are generally useless due to the fact that these lymph nodes would have to double or triple their size in order to be visualized on computed tomography (CT), or magnetic resonance imaging, except for positron-emission tomography, which can potentially display even non-enlarged lymph nodes. Interestingly, even considering the fact that this problem has been investigated for over 40 years, and many articles have been published, no clear conclusion has been made so far, and conflicting results continue to be reported (10). The clinical practice differs significantly from one center to another, ranging from avoiding any procedure for this group of lymph nodes, regardless of whether these are visualized during the SLNB, to surgical biopsy or radiotherapy of IMNs in all patients.…”

Prognostic value of the lymph node ratio for lymph-node-positive breast cancer- is it just a denominator problem?

“…In other words, could the survival and loco-regional control benefit of radiation be simply due to under-staging and, does the recent Oxford meta-analysis really mean that every patient with 1–3 nodes positive require post-mastectomy radiation (Zhou et al 2013 ). Further, there is ongoing debate, not only about the use of radiation, but also the areas to be treated particularly with respect to the internal mammary chain (Vrana et al 2013 ).…”