Clinicopathological features of gastric metastasis from breast cancer in three cases.

The common sites for metastases from breast cancer are lymph nodes, bone, lung, liver, and brain. Gastrointestinal (GI) metastasis is rarely found or diagnosed in patients with breast cancer. This report presents three cases of gastric metastasis from breast cancer. Case 1 was a 42-year-old female diagnosed with gastric metastasis after mastectomy with axillary lymph node dissection for invasive lobular carcinoma of the left breast. Case 2 was a 54-year-old female who was diagnosed to have invasive lobular carcinoma of the left breast with systemic bone and gastric metastasis. Case 3 was a 54-year-old female who was diagnosed to have bilateral invasive ductal carcinoma of the breast with simultaneous bone and gastric metastasis. The immunohistochemical statuses for estrogen receptor, progesterone receptor, mammaglobin, and gross cystic disease fluid protein-15 (GCDFP-15) between the primary and gastric metastatic lesions were all well matched. All three cases were treated with systemic chemotherapy, hormone therapy or both, without surgical intervention for gastric lesions. Two patients with disseminated disease died 27 and 58 months after diagnosis of gastric metastasis, while one patient without organ metastasis is still alive at 56 months after diagnosis. It is important to make a correct diagnosis by distinguishing gastric metastasis from breast cancer in order to select the optimal initial treatment for systemic disease of breast cancer.