Orbital metastases from breast cancer: A single institution case series

Introduction: Among orbital tumors, metastatic lesions show a prevalence of 1-13%; on the other hand, breast cancer is the most common malignancy causing orbital metastases. The aim of our study is to present our experience dealing with orbital metastases caused by breast cancer, to assess characteristics and clinico-pathological data of patients suffering from this rare occurrence and to find indexes related with their prognosis and survival. Methods: Records of patients diagnosed with orbital metastases from breast cancer at the Department of Ophthalmology, Humanitas Clinical and Research Centre of Milano over a 27-year period (1992-2018) were retrieved and analyzed. Overall, 28 patients presented this rare occurrence during the study period. Results: Patients’ age at breast cancer diagnosis was 56.29±14.63 years. Mean time interval between breast cancer diagnosis and orbital metastasis occurrence was 5±4.17 years. All lesions were estrogen receptor-positive; 79% of patients harbored progesterone receptor-positive lesions. MIB-1 was < 20 in 8 cases, between 20 and 50 in 10 and > 50 in the remaining 10 patients. Interestingly, the majority of deceased patients presented orbital lesions with MIB-1 index >50% (P=0.0265) and had concomitant lung metastases (P=0.0452). Conclusion: The occurrence of orbital metastasis represents an important and challenging finding. Patients’ clinical picture can include proptosis, diplopia, exophthalmos/enophthalmos and/or blurry vision, which should raise suspicion of a possible orbital metastatic lesion, particularly in patients with history of breast cancer. Significant symptomatic improvement can be achieved through surgery and other adjuvant treatments, such as radiation therapy and chemotherapy.