Small bowel obstruction as the primary presentation of undiagnosed metastatic lobular breast carcinoma.

Breast carcinoma continues to be the most common neoplasm in women, with a lifetime risk affecting approximately 1 in 8. Factors affecting prognosis include the size and grade of the primary lesion, regional axillary lymphadenopathy, the presence of hormonal receptors, and distant metastatic disease. Although metastatic breast disease usually affects the lungs, bones, and brain, abdominal association is not as common. Interestingly, lobular carcinoma, a subtype that only accounts for a minor portion of breast cancers, usually has luminal gastro-intestinal involvement. We describe a 57-year old Caucasian female with recurrent episodes of abdominal pain and concurrent intermittent obstructive symptomatology with overflow diarrhea over a one-year period. Conventional endoscopic and imaging workup was unrevealing. Capsule endoscopy was used, but this caused a complete bowel obstruction necessitating surgery, and subsequent resection of a strictured segment. Pathological examination yielded metastatic adenocarcinoma, consistent with origin in breast, lobular type. Immunohistochemistry confirmed the origin. Luminal gastro-intestinal involvement is a rare, yet recognized, site of breast adenocarcinoma metastasis; it is even more uncommon with an undiagnosed primary. It may mimic other gastro-intestinal disease, and as such, it would be prudent to maintain a modest index of suspicion given the high prevalence of breast neoplasia.