Breast Cancer Orbital Metastases: Clinical and Histopathological Characteristics, Imaging Features, and Disease-Related Survival in a Multicentric Retrospective Case Series

<b>Background</b>: This study aims to analyze the clinical, radiological, and histopathological features, as well as the long-term follow-up, of patients with breast carcinoma orbital metastases. <b>Methods</b>: The study was a multicentric retrospective observational case series. The medical records of 32 female patients affected by breast carcinoma orbital metastases referred to three tertiary referral centers from January 2016 to December 2023 were reviewed. The demographic characteristics of the population, clinical ophthalmological presentation, histological features, orbital metastasis latency, disease-related survival (DRS), and mortality rate were analyzed. <b>Results</b>: The median age of the patients was 62.50 years (interquartile range (IQR): 74.50-57.50). The prevalent histotype of the orbital metastases of breast cancer was lobular carcinoma (75.00% of cases). The median orbital metastasis latency time was 39.50 months (IQR: 134.00-10.25). The median disease-related survival (DRS) during the observational period was 35 months, and the 24-month survival rate was 70.73%. The overall mortality rate in our population was 50%. <b>Conclusions</b>: The most frequent histotype of breast cancer orbital metastasis is lobular carcinoma. The primary tumor precedes the onset of orbital metastasis in most cases and usually presents as a mass occupying space and infiltrating the orbit. Orbital metastases are a sign of an advanced stage of the disease, which has a high mortality rate and a low DRS.