title: Occult carcinoma of the breast masquerading as primary adenocarcinoma of the small intestine. A case report.
abstract: A fifty-year-old woman with abdominal pain, diarrhea, and weight loss ultimately required exploratory laparotomy. The entire small intestine was extensively infiltrated by poorly differentiated adenocarcinoma; mesenteric lymph nodes and surrounding omentum were involved, but no extragastrointestinal tumor was found. A presumptive diagnosis of unresectable primary carcinoma of the small bowel was made. Chemotherapy was initiated with 5-fluorouracil 300 mg/m2/day by continuous intravenous infusion. Nine months later a left breast mass with multiple ipsilateral axillary and supraclavicular lymph nodes developed; biopsy revealed a poorly differentiated adenocarcinoma morphologically identical to the tumor involving her small bowel. In spite of breast irradiation and systemic hormonal therapy, the patient deteriorated rapidly and died from progressive metastatic disease.
authors.affiliation: Department of Medicine, Medical College of Wisconsin, Milwaukee.
authors.forename: R M
authors.initials: RM
authors.lastname: Hansen
authors.forename: J D
authors.initials: JD
authors.lastname: Lewis
authors.forename: N A
authors.initials: NA
authors.lastname: Janjan
authors.forename: R A
authors.initials: RA
authors.lastname: Komorowski
mesh_terms: D001943:Breast Neoplasms / Q000473:pathology*; D002285:Carcinoma, Intraductal, Noninfiltrating / Q000473:pathology / Q000556:secondary*; D005260:Female; D006801:Humans; D007414:Intestinal Neoplasms / Q000473:pathology / Q000556:secondary*; D007421:Intestine, Small; D008875:Middle Aged; D009382:Neoplasms, Unknown Primary / Q000473:pathology*