Abstract
A 71-year-old woman had been treated with breast-conserving surgery (Bq+Ax) for the left breast 13 years previously. An enlarged lymph node was noted in her right axilla. A core needle biopsy of the lymph node revealed metastasis of the adenocarcinoma, resulting in the suspicion of breast cancer. A magnetic resonance imaging scan revealed a tumor near the surgical scar in the left breast. The tumor was diagnosed as invasive ductal carcinoma by an ultrasound-guided vacuum-assisted biopsy. Lymphoscintigraphy showed lymphatic flow from the left breast to the right axilla and left parasternal area. According to this finding, the patient was diagnosed with contralateral axillary lymph node metastasis. Left total mastectomy, right axillary lymph node dissection, and left parasternal lymph node biopsy were performed. No metastasis was found in any of the remaining right axillary lymph nodes ; except for an enlarged node and a left parasternal lymph node. The patient received adjuvant therapy (HCN+wPTX) and has remained free of disease for 18 months. A change was observed in the lymphatic flow from the left breast. The aberrant lymphatic flow was thus deemed to have caused the contralateral axillary lymph node metastasis. These irregular occurrences were identified based on the findings of a sentinel lymph node biopsy.
