Malignant melanoma of the choroid presenting as orbital cellulitis: report of two cases with a review of the literature.

Orbital cellulitis can be the initial presentation of malignant melanoma of the choroid when such tumors undergo necrosis or extrascleral extension. We report two unusual cases of malignant melanoma of the choroid presenting with gradual dimness of vision for only two months. Histopathology revealed malignant melanoma of the choroid with extensive necrotic hemorrhages within the tumor. There was extensive infiltration of the sclera with acute inflammatory cells. No evidence of intra- or extrascleral extension by the tumor was seen. Metastatic work-up revealed no evidence of secondary deposits. An unusual presentation of malignant melanoma of the choroid is reported, together with the pathogenic mechanisms and a review of the literature.