Cutaneous Melanoma Metastatic to the Orbit

PURPOSE: To describe the clinical features, management, and outcomes of 15 patients with cutaneous melanoma metastatic to the orbit. The authors review emerging treatments for metastatic melanoma and their ocular implications. METHODS: Retrospective chart review of 15 patients with orbital metastasis from cutaneous melanoma. RESULTS: At presentation of the orbital metastasis, systemic metastatic cutaneous melanoma was present in 13 (87%) patients. The mean interval from diagnosis of cutaneous melanoma to orbital metastasis was 40 months (median, 37 months; range, 0-117 months). The most common presenting signs were dysmotility (63%), proptosis (56%), and blepharoptosis (19%). Four patients (25%) presented with pain. Metastasis involved extraocular muscle in 6 orbits (35%), intraconal space in 4 (24%), extraconal space in 7 (41%), and lacrimal sac in 1 (6%). The tumor was unifocal in all cases, unilateral in 13 patients (87%), and bilateral in 2 (13%). The mean tumor basal dimension was 20 × 20 mm and mean thickness was 16 mm. Treatments included complete surgical excision in 1 patient (6%), external beam radiotherapy (EBRT) in 7 (47%), systemic chemotherapy in 8 (53%), and immunotherapy in 5 (33%). Orbital tumor control was achieved in 2 orbits (18%) following focal therapy alone (excision or EBRT), 4 (36%) following systemic therapy alone (chemotherapy or immunotherapy), and 3 (27%) following combination focal plus systemic therapy. Three patients required exenteration. Survival rates at 1 year/2 years were 100%/0% following focal therapy, 50%/25% following systemic therapy, and 100%/66% following combination therapy. CONCLUSIONS: Cutaneous melanoma metastatic to the orbit tends to involve muscle (35%) or intraconal soft tissue (24%) as a painless (75%), circumscribed (87%) mass. Treatment with systemic chemotherapy and/or immunotherapy resulted in orbital tumor control in 80% of cases. Overall survival was 25.1 months.