RESUMO
INTRODUCTION: Breast cancer metastasis to the gastrointestinal (GI) tract is rare and occurs more frequently in invasive lobular carcinoma. Patients may be asymptomatic or present with variable vague symptoms that may be mistakenly attributed to side effects of chemotherapy or other benign GI diseases. Treatment follows the principles of systemic disease and includes hormonal therapy, chemotherapy and signal transduction inhibitors, with surgical intervention indicated for complications such as obstruction, perforation and hemorrhage. PRESENTATION OF CASE: We present the case of a female patient with a history of invasive lobular breast carcinoma who had undergone mastectomy and axillary dissection, followed by chemoradiotherapy. Over the next nine years, she developed ovarian and bone metastases for which appropriate treatment was provided. A right iliac fossa mass was discovered during routine clinic review, though she remained asymptomatic. Computed tomography scan showed ileocecal intussusception. Histopathological examination of the right hemicolectomy specimen following emergency surgery confirmed metastatic invasive lobular carcinoma to the GI tract. DISCUSSION: GI tract metastasis may present 30 years after the primary breast cancer. Up to 20% of patients may be asymptomatic as shown by Montagna et al. When present, symptoms are commonly non-specific and vague. Histological diagnosis is challenging. GI metastasis typically appears as intramural infiltration of the bowel wall by small cells arranged in cords. CONCLUSION: It is important to maintain a suspicion for GI tract metastasis in breast cancer patients who present with abdominal mass or GI symptoms, as this aids in prompt institution of accurate and appropriate management.