Abstract
Purpose :
Intraocular and orbital metastases are rare and indicate hematagenous dissemination of a primary cancer. The orbit and the choroid are the most common sites for ocular involvement for disseminating malignancies. Immunohistochemistry (IHC) using a panel of antibodies is useful to determine the nature of the metastatic tumor even in patients with no known primary cancer. The objective of this study is to report twelve unusual metastases to the eye and the orbit diagnosed using IHC methods.
Methods :
Over a ten year period (2007-17), 30 metastatic tumors to the eye and orbit were retrieved from the MUHC-McGill University Ocular Pathology Laboratory. In total, 12 of these 30 cases were selected based on unusual presentation, complete clinical history and imaging, availability of both primary and metastatic tissue, as well as a comprehensive IHC profile. The immunomarkers included: CD4, CD20, CK-8/18, CK-7, HMB45, S-100, Melan-A, CD138, synaptophysin, chromogranin, vimentin, desmin, estrogen, progesterone, and BRST-1 and -2.
Results :
Of the 12 cases, nine were orbital and three were intraocular (choroidal). Six of the orbital cases were ductal carcinoma of the breast metastatic to the orbit. Five of these six were BRST-1 and -2 positive, while the other case was CK-7, estrogen, and progesterone positive. The primary tumor of this latter patient was BRST-1 and -2 positive. Three of these six presented as bilateral proptosis while the other three had unilateral orbital involvement. The remaining three orbital cases were diagnosed as a conjunctival malignant melanoma, cutaneous melanoma, and alveolar soft part sarcoma. The IHC profile of melanoma cases were HMB45 and Melan-A positive. The alveolar sarcoma was positive for vimentin and desmin. The three intraocular uveal tumors included a metastatic carcinoid, plasmacytoma (multiple myeloma), and T-cell lymphoma. Chromogranin and synaptophysin were positive for the metastatic carcinoid, CD-138 was positive in the plasmacytoma, and the T-cell lymphoma was positive for CD4.
Conclusions :
Even though metastasis to the eye or orbit is rare, an accurate diagnosis is crucial for patient treatment. IHC evaluation of the metastasis is the gold standard to establish a correct diagnosis. A panel of IHC markers is always required as metastatic tumors may have a different profile compared to the primary tumor.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.