A Case of Metastatic Breast Cancer Presented with Obstructive Jaundice Despite Pathological Complete Response after Neoadjuvant Chemotherapy that Mimicked Pancreatic Cancer

Abstract

We report a rare case of obstructive jaundice due to solitary para-aortic lymph node metastasis after breast cancer surgery. The patient was a 45-year-old woman. She was diagnosed with left breast cancer cT1N1M0 cStage IIA triple negative type and was treated with neoadjuvant chemotherapy. She underwent left breast partial mastectomy and axillary lymph node dissection, and achieved a pathologic complete response (pCR). Fourteen months after the surgery, the patient presented to our hospital with fatigue. Blood biochemistry tests showed elevated levels of hepatobiliary enzymes, and a CT scan of the abdomen showed soft shadows from the hilar region to the para-aortic region, which led us to suspect pancreatic cancer. However, endoscopic ultrasonography revealed no obvious tumor in the pancreas, which was thought to be enlarged para-aortic lymph nodes. Endoscopic ultrasonography-guided fine-needle aspiration biopsy of the same site revealed that the primary site was difficult to identify because the results were consistent with both mammary and pancreatic sites. However, we considered it to be a primary mammary gland tumor based on comprehensive consideration of the patient's medical history, imaging studies, and histopathological examinations. Weekly paclitaxel + bevacizmab (wPTX + Bev) therapy was effective, and she is currently maintaining a complete clinical response (cCR).