Assessment of the value of congenital hypertrophy of the retinal pigment epithelium as an ocular marker for familial adenomatous polyposis coli.

The presence of bilateral, multiple patches of congenital hypertrophy of the retinal pigment epithelium (CHRPE) is cited as an early phenotypic marker of the familial adenomatous polyposis coli (FAPC) gene. However, the degree of concordance between CHRPE and the presence of familial adenomatous polyposis (FAP) has not been adequately assessed in individual families. We studied the eyes of 28 members of a single kindred spanning three generations with FAPC; 14 were affected and 14 unaffected but 'at risk'. Six affected and 8 unaffected at risk individuals possessed a total of 34 retinal lesions, 17 in each group. Two affected individuals and 1 at risk individual had the classical pattern of CHRPE associated with FAPC. The sensitivity of CHRPE as an ocular marker for FAPC in this kindred was 14.2%. Our findings have implications for the use of CHRPE for the presymptomatic screening of family members at risk of FAPC. Therefore, ocular examination should not replace colonoscopic screening in an individual at risk of FAPC.