Breast Cancer with Internal Mammary Node Metastases: A Case Presented in a Tumor Board Session and Decision Making

Background: There are several therapeutic options available for breast cancer treatment, now incorporating innovative targeted molecular therapies. Metastatic breast cancer is usually treated with chemotherapy and/or hormonotherapy. Surgery has not been shown to improve survival. Adjuvant radiotherapy (RT) has been proven to be effective in the treatment of locally advanced breast cancer, reducing locoregional recurrence. The optimal treatment of internal mammary lymph nodes (IMN) metastases remains controversial. Case presentation: A 48-year-old woman was diagnosed with invasive breast cancer with ipsilateral metastases to axillary lymph nodes and a contralateral IMN metastasis. This case was presented twice during the tumor board sessions of the Surgical Oncology Service at the Centre hospitalier de l'Université de Montréal (CHUM), Montréal, Canada. Question: Does the internal mammary chain (IMC) dissection could be used as a treatment approach in breast cancer with IMC metastasis? Conclusion: Internal mammary chain dissection should be discussed in tumor board sessions on a case-by-case basis. There are no strong guidelines on the management of IMN metastasis in breast cancer, but there is growing evidence that these women should be treated with curative intent.