Metastatic Breast Cancer Presenting as a Subconjunctival Mass

Breast cancer is the most common primary source of orbital metastasis. Metastasis occurs through hematogenous spread and predominantly involves the choroid. We present a case of a metastatic subconjunctival mass associated with primary breast cancer. To our knowledge, this is the first reported case of its kind. A 41-year-old woman presented with complaints of conjunctival injection and a foreign body sensation in the left eye. She had a history of breast cancer and had been treated 2 years previously with modified radical mastectomy followed by adjuvant radiotherapy and chemotherapy. Slit-lamp examination showed a cystic mass under the temporal bulbar conjunctiva, associated with dilated overlying conjunctival vessels. An excisional biopsy revealed a poorly differentiated adenocarcinoma. Positron emission tomography examination for systemic malignancy revealed multiple systemic metastasis. Metastatic disease should be considered in the differential diagnosis of subconjunctival lesions, and ophthalmic manifestations can play an important role in the detection of metastatic spread of a known primary breast cancer.