A case of breast meningeal carcinomatosis caused by trastuzumab treatment as adjuvant chemotherapy

A 52-year-old woman underwent modified radical mastectomy and axillary lymph node resection for right breast cancer (stage II B). Afterwards FEC therapy (5-FU 500 mg/m², epirubicin 75 mg/m², cyclophosphamide 500 mg/m²) X4, docetaxel therapy (60 mg/m ²) X 4 and radiation of the illness side collarbone, upper and lower lymph nodes were enforced for adjuvant therapy after the operation. Furthermore, administration of aromatase inhibitor (anastrozole) and trastuzumab was started due to the postoperative pathological diagnosis of hormone receptor-positive and HER2 (score 3+). This became an urgent hospital admission because of the sudden escape power from impaired consciousness due to the articulation disorders and limb weakness when trastuzumab was administered nine times. It was diagnosed by MRI examination and the cerebrospinal fluid cytology as meningeal carcinomatosis of breast cancer, and she died on the 31st recurrence of disease. A serious relapse may be caused in a case of fast-progressing breast cancer like this while being administered trastuzumab as an adjuvant treatment.