Implantation growth of an iris melanocytic lesion simulating a ciliary body melanoma

A 59-year-old woman had a sectorial pigmented iris tumor in her right eye and was found to have secondary glaucoma unresponsive to medical therapy. Gonioscopy revealed a satellite tumor in the inferior chamber angle, which we suspected to be a ciliary body melanoma. Subsequently, both lesions were removed completely by superior total and inferior partial iridocyclectomy. Histologic examination disclosed a spindle cell nevus with surface plaque associated with a borderline epithelioid cell nevus. This case is an example of unexpected clinical findings that may be encountered in any iris melanocytic lesion, benign or malignant, and the consequent problems of diagnosis and management.