Management of choroidal malignant melanoma at Iowa.

Approximately 50% of patients undergoing enucleation for choroidal melanoma will eventually die of metastases. The majority of tumor related deaths will occur within 5 years of enucleation, but late metastases may occur 20-30 years after enucleation. Long-term follow-up of patients refusing treatment has shown a 100% mortality. Although recent reports have attempted to link the performance of enucleation with the development of metastases, examination of available data suggests that metastases occur preoperatively, but are subclinical at the time of enucleation. The most important variable determining prognosis in these cases is the size of the tumor at the time of diagnosis and treatment. Patients who undergo enucleation before the tumor exceeds 7 X 7 X 2 mm have an extremely favorable prognosis. Patients whose maximum tumor diameter exceeds 12 mm have an extremely poor prognosis. Metastases and extrascleral extension have both been reported to occur in tumors which failed to demonstrate growth while being followed. For these reasons we recommend immediate enucleation be carried out in all patients whose tumors exceed 7 X 7 X 2 mm and in whom the diagnosis can be confirmed by indirect ophthalmoscopy, ultrasound, fluorescein angiography, and other tests. Follow-up of non-enucleation methods of treatment of choroidal melanomas is too short to draw meaningful conclusions. The consistent finding of persistence of some tumor mass and the histopathologic presence of viable tumor cells following these treatment modalities leaves us very concerned about the long-term results in these patients. Late metastases continue to occur decades following diagnosis of a choroidal melanoma, especially if it is small. The ophthalmologist must remain aware that the results of his decision concerning treatment of a melanoma may not become apparent for many years.