FAMILIAL UVEAL MELANOMA .3. IS THE OCCURRENCE OF FAMILIAL UVEAL MELANOMA COINCIDENTAL

Objective: To ascertain whether the familial occurrence of uveal melan oma was coincidental in kindreds in which 1 first-degree relative of t he proband had also been affected with primary uveal melanoma. Patient s: In a series of 4500 patients with primary uveal melanoma, 17 kindre ds were identified in which a first-degree relative of the proband had also been affected with primary uveal melanoma. Design: In the 17 fam ilies in which a first-degree relative of the proband had been affecte d, primary uveal melanoma was classified as familial. In the remaining 4483 families, primary uveal melanoma was classified as sporadic. The expected number of affected first-degree relatives of probands for a family was estimated, assuming an incidence rate of 6 cases per millio n population per year in each type of family. Results: The expected nu mber of affected first-degree relatives was calculated to be 0.81, wit h an SE of 0.08, compared with 17 observed affected first-degree relat ives (P<.001). Conclusion: Our study provides strong statistical evide nce that occurrence of familial uveal melanoma is not coincidental.