Prognostic value of the disodium phosphate 32P uptake test in uveal melanoma: a long-term study.

OBJECTIVE To evaluate whether nuclear activity as measured by the disodium phosphate 32P (32P) uptake test for uveal melanoma is of prognostic value and corresponds to known prognostic factors. METHODS A retrospective analysis of 121 patients with choroidal and/or ciliary body melanoma, tested with the 32P uptake test before enucleation between January 1, 1973, and December 31, 1976, at the Leiden University Medical Center. We obtained the 25-year follow-up information of this group of patients and compared the 32P test results and histopathological variables with the long-term survival rates. RESULTS The cumulative 5-, 10-, and 20-year survival for melanoma-related death was 81.4%, 73.3%, and 63.9%, respectively. The results of the 32P uptake test were not significantly correlated with survival (P =.35). Of all prognostic factors under study, tumor diameter, cell type, and mitotic count were identified as the most important prognostic markers for uveal melanoma in this group. CONCLUSIONS The 32P isotope uptake test has no prognostic value for uveal melanoma. Moreover, the results of this study indicate that it is unlikely that cell activity as determined by 32P uptake involves mitotic activity of the tumor.