Abstract
The patient was a 61-year-old woman. She had undergone modified radical mastectomy with axillary lymph node dissection for left breast cancer in 1993, when the histopathological diagnosis was invasive lobular carcinoma, n=8/12, estrogen receptor (ER) (+), and progesterone receptor (PR) (+). Postoperative radiation therapy at a dose of 50Gy was given to the patient (the left supraclavucular area, left axilla, and parasternal area). Postoperative chemotherapy with tamoxifen citrate (20mg/day) and fluorouracil (200mg/day) was conducted for 3 years, and then the patient had been free from recurrence for postoperative 10 years. She became to have lower abdominal pain in August 2003, and her clinical course was followed. However, the symptom became worse, and lower gastrointestinal endoscopy conducted in July 2004 disclosed redness and stenosis encircling the lumen of rectum. A biopsy of the narrowing lesion suggested poorly differentiated adenocarcinoma. It was a diffuse lesion forming no tumor which was non-typical as rectal cancer so that metastasis of breast cancer was suspected as well. Immunostaining resulted in ER (+) and PR (+) which were identical with those of the primary lesion. From these findings rectal metastasis of breast cancer was diagnosed. Oral exemestane (25mg/day) was started which gave a relief of the abdominal symptom 2 months after its initiation. She has been followed in the clinic at present when 22 months have elapsed after the drug regimen.
