METASTATIC BREAST CARCINOMA TO THE VITREOUS

In Brief Purpose: To evaluate the clinical and pathologic findings in two patients with prior breast carcinoma who underwent diagnostic vitrectomy for vitreous opacities and preretinal membrane. Methods: The clinical histories and ophthalmic findings in two patients were reviewed. Vitrectomy specimens from the patients were processed by cytospin and standard tissue techniques, stained with hematoxylin and eosin, and examined immunohistochemically for cytokeratins. The original breast carcinoma specimens were reviewed. Results: The vitreous in both patients contained malignant cells with cytologic features consistent with metastatic carcinoma. Immunohistochemical stains were positive for cytokeratins in the cells. The cytologic findings in the vitreous cells resembled the primary breast carcinoma. Conclusions: Breast carcinoma may metastasize to the vitreous, most likely via the retina. The clinical manifestations include vitreous cell and preretinal membrane. The most common site of intraocular metastasis is the uveal tract. Rarely, carcinoma may metastasize to the retina/vitreous. Few cases are confined to the retina/vitreous, as the tendency is to also metastasize to other ocular structures. The authors recently evaluated two patients with metastatic breast carcinoma to the vitreous without evidence of metastasis to other ocular structures.