Detailed Ophthalmic and Pathological Features of Choroidal Metastasis From Breast Cancer: A Case Series of Five Patients

Breast cancer causes choroidal metastases on rare occasions. This study presented the eye manifestations of choroidal metastases from breast cancer and their response to treatments in detail as well as their pathological correlation in five patients. The patients' age at the diagnosis of breast cancer ranged from 24 to 69 years (median: 37 years). The time from the diagnosis of breast cancer to the detection of metastases was concurrent in one patient, two years later in three patients, and six years later in the other patient. The time from the detection of systemic metastases to the detection of choroidal metastases was the same in one patient, while it ranged from one to seven years later in four patients. Choroidal metastases were in the unilateral eye of four patients, whereas they were in both eyes of one patient. Choroidal metastases manifested as one or a few nodular or flat choroidal lesions with serous retinal detachment. As for the treatment of choroidal metastases, enucleation of the right eye was chosen based on the patient's wish as well as the family's wish in the earliest patient when cancer notification was not the norm in Japan. In the other four patients, whole-eye radiation was performed to reduce the choroidal metastatic lesions. As regards the prognosis, which was available in four patients, three patients died within one year from the diagnosis of choroidal metastases, while one patient died one year and eight months later. Regarding the pathology of breast cancer, which was available in four patients, immunostaining of the preserved enucleated eye in the earliest patient revealed that breast cancer cells in the choroidal metastatic lesion were positive for estrogen receptor and negative for progesterone receptor and human epidermal growth factor receptor 2 (HER2). Invasive ductal carcinoma in two patients was positive for estrogen receptor and negative for HER2, while invasive ductal carcinoma in the other patient was triple-negative for estrogen receptor, progesterone receptor, and HER2 with a high Ki-67 index. In conclusion, the prognosis for life was poor in patients with breast cancer who developed choroidal metastases. Choroidal metastatic lesions showed a response to whole-eye radiation to improve the quality of vision at the end of life. Vision-related symptoms should be monitored in the course of chemotherapy for systemic metastases.