Is Sentinel Node Biopsy of the Internal Mammary Lymph Nodes Relevant in the Management of Breast Cancer?

Abstract

The aim of this study was to review the outcomes of a series of breast cancer patients who underwent sentinel node biopsy inclusive of lymphoscintigraphy, and to assess the incidence of internal mammary node (IMN) metastatic positivity at exploration and whether these findings influenced treatment. Between April 2001 and December 2012, 581 breast cancer patients at Princess Alexandra Hospital underwent preoperative lymphoscintigraphy in the course of the performance of sentinel node biopsy. Analysis was performed of those patients who demonstrated radio-isotope uptake to the IMN chain, and who had sentinel node biopsy of the IMN's and were found to have metastatic involvement. Assessment was made to determine whether the finding of IMN metastases changed the adjuvant systemic management of these patients, and to review complication rates. 95 of 581 (16.4%) patients with preoperative breast lymphoscintigraphy had lymphatic mapping to the IMN chain. 51 (54%) of these patients had IMN chain surgically explored and IMN nodes were found in 35 of these patients (success rate of 69%). Of these, three patients (3/35 = 8.6%) had metastatic involvement of the IMN sentinel node group. All three IMN positive patients received adjuvant breast radiotherapy, chemotherapy, and hormonal therapy. In four patients (7.8%) IMN surgical exploration was complicated by pneumothorax. Only a small proportion of breast cancer patients were found to have metastasic involvement of the IMN chain and which did not significantly change their adjuvant therapy management. These findings suggest that the benefits of exploration of the IMN chain in breast cancer patients are limited and may be outweighed by the risk of complications.

Internal mammary node positivity and autologous mastectomy reconstruction: Implications for breast cancer treatment and aesthetic outcome

“…Despite pneumothorax as a well-described complication of these biopsies previously, we have had no episodes of pneumothorax or lymphatic leak associated with these biopsies performed concurrently with the free DIEP fl ap reconstruction [13].…”

“…The status of these nodes provides additional prognostic information to potentially guide systemic therapy and/or radiotherapy [9][10][11][12]. Routine evaluation of the internal mammary lymph nodes remains cumbersome due to the relative diffi culty in accessing these nodes surgically and the limitations of preoperative imaging for detection of microscopic internal mammary lymph node involvement [13]. The histologic status of the internal mammary lymph nodes carries the same prognostic signifi cance as the status of the axillary lymph nodes and is based on the number of pathologically abnormal nodes [i.e., pN1 (1-3 positive axillary or internal mammary lymph nodes) and pN2 (4-9 positive axillary or internal mammary lymph nodes)].…”

“…Sentinel lymph node biopsy of the internal mammary node was described in Australia where the incidence of breast cancer is higher (94.5 per 100,000) than in the United States (85.9 per 100,00) [13]. Internal mammary sentinel node biopsy has not been adopted in the United States or worldwide.…”

The poor prognosis of lower-inner quadrant breast cancer in patients who received neoadjuvant chemotherapy

“…Nevertheless, the definition of nodal pCR is evaluated based on the pathological state of the ALNs but ignores the pathological state of the IMNs. Accordingly, considerable studies have explored magnetic resonance imaging (MRI), positron emission tomography-computed tomography (PET-CT), sentinel node biopsy, and other methods for their ability to make a better diagnosis of IMN, with few tools currently available to assist clinicians (15)(16)(17). The benefits of the exploration of diagnostic methods based on the IMN chain in breast carcinoma patients are limited and are likely to be refused by patients due to the risks associated with the complications (17).…”

Internal mammary lymph node metastasis in breast cancer patients based on anatomical imaging and functional imaging

“…Early clinical trials have shown that the internal mammary lymph node (IMLN) status is an important prognostic factor for breast cancer, and knowledge of the IMLN status is essential to guide the treatment strategy [1][2][3][4]. However, recently clinical trials have indicated that IMLN metastasis does not independently predict overall survival (OS) and progression-free survival (PFS) for patients who receive personalized treatment (e.g., chemotherapy, endocrine treatment, targeted treatment, and radiotherapy) [5][6][7][8][9]. Thus, accurate staging plays a significant role in guiding effective, multidisciplinary, and personalized treatment for newly diagnosed breast cancer patients.…”