The significance of the 32-P uptake test in the diagnosis of posterior uveal melanomas.

One hundred consecutive histologically confirmed malignant melanomas of the posterior uvea; on which the 32-P test was performed prior to enucleation, were classified according to cell type. The 32-P uptake results of the pure spindle cell melanomas were compared with the results in the mixed and epithelioid cell tumors. There appears to be no relationship between 32-P uptake and cell type using the Callender classification. The 32-P uptake results in the 100 melanomas were then compared with the results in teh 30 benign lesions which are known to simulate melanoma occasionally. There was a significant difference in 32-P uptake between the benign and malignant lesions, and no false-positive results were encountered. The importance of the 32-P test as a diagnostic adjunct for malignant intraocular tumors is emphasized.