Background. Breast carcinoma is the most common malignancy in women. Gastrointestinal metastasis is rarely found or diagnosed in patients with breast cancer. Methods. Clinicopathological features, treatment options, and prognosis were evaluated retrospectively for 22 patients with gastrointestinal metastases of breast carcinoma in Chinese women. Results. Presenting symptoms were non-specific: anorexia (21/22), epigastric pain (10/22), and vomiting (8/22), and 2 patients (2/22) presented with nonfatal hemorrhage. The first sites of metastases were skeleton (9/22), stomach (7/22), colorectal (7/22), lung (3/22), peritoneal (3/22), and liver (1/22). ER, PR, GATA binding protein 3 (GATA3), gross cystic disease fluid protein-15 (GCDFP-15), and keratin 7 can effectively confirm the diagnosis, especially in the case of keratin 20 negativity. Histology showed mainly ductal breast carcinoma (n = 11) was the predominant source of gastrointestinal metastases in this study, and lobular breast cancer (n = 9) accounted for a considerable proportion. The disease control rate to systemic therapy was 81% (17 of 21 treated patients), and the objective response rate was 10% (2 of 21 treated patients). Median overall survival was 71.5 months (range, 22-226 months), median survival for distant metastases was 23.5 months (range, 2-119 months) and the median survival for the time of gastrointestinal metastases diagnosis was 6 months (range, 2-73 months). Conclusions. Performing the endoscopy with biopsy was crucial for patients with any subtle gastrointestinal symptoms and a history of breast cancer. It is important to distinguish primary gastrointestinal carcinoma from breast metastatic carcinoma in order to select the optimal initial treatment and avoid unnecessary surgery.
Keywords: breast carcinoma; gastrointestinal metastasis; lobular carcinoma; treatment.