Intraocular Metastases Secondary to Breast Carcinoma Correlates With Upregulation of Estrogen and Progesterone Receptor Expression in the Primary Tumor.

PURPOSE To compare estrogen (ER), progesterone (PR), and human epidermal growth factor-2 (HER2) receptor expression in the primary tumor of patients affected by choroidal metastases from breast carcinoma (BC) versus those with extraocular metastases. METHODS Eighteen consecutive patients affected by choroidal metastases from BC were included. We defined ER, PR, and HER2 positivity of the primary tumor following standard guidelines. Breast carcinoma molecular subtypes were also identified (luminal A, luminal B, HER2-enriched, and triple negative). Forty consecutive patients affected by metastatic BC without choroidal involvement were included as a control group. RESULTS The study group and the control group were similar for age, sex, race, histopathologic classification of the primary tumor (ductal, lobular, others), and American Joint Committee on Cancer Tumor-Node-Metastasis stage at the time of primary tumor diagnosis (P > 0.05). Patients affected by choroidal metastases from BC showed a significantly higher expression of ER (P = 0.009) and PR (P = 0.018) receptors in the primary tumor compared with nonchoroidal metastatic BC. Across all patients, the luminal B molecular subtype was related to the presence of choroidal involvement (P = 0.003). Considering luminal tumors only, the luminal B subclassification was also related to the presence of choroidal involvement (P = 0.009). CONCLUSIONS Choroidal metastases from BC are associated with ER and PR expression in the primary tumor and the luminal B molecular subtype.