[Orbital and stomach metastasis from invasive lobular breast carcinoma]

Orbital or ocular metastatic tumors may originate from breast cancer. Few studies have been made regarding their histopathological classification. A 71-year-old female noted a tumor in the right orbital region. She had had bilateral breast cancer 2 years before and gastric cancer 5 months before. Histopathology had shown stage II invasive ductal cancer (scirrhus) in the right breast and stage III invasive lobular cancer in the left. Signet-ring cells were present in the breast and gastric cancers. Biopsy of the right lower eyelid showed poorly differentiated adenocarcinoma with signet-ring cells. Indian file pattern, which is specific for invasive lobular cancer, was also present, suggesting that the orbital tumor had metastatized from the left breast cancer. Genetic analysis of the gastric cancer using polymerase chain reaction showed a mutation at exon 8 of the p53 tumor suppressor gene, indicating the cancer to be metastatic. These results led to the conclusion that invasive lobular cancer of the left breast was the primary lesion for the gastric and orbital metastases. This case also illustrates that signet-ring cells, which are usually seen in gastric cancer, may be present in invasive lobular breast cancer and in orbital metastasis.