Role of congenital hypertrophy of the retinal pigment epithelium in the predictive diagnosis of familial adenomatous polyposis

Abstract

A study was carried out to evaluate congenital hypertrophy of the retinal pigment epithelium (CHRPE) as a disease marker in a defined population with familial adenomatous polyposis (FAP). Indirect ophthalmoscopy was performed on 75 individuals from 25 known families with FAP, of whom 32 were known to be affected and 43 were at a 50 per cent prior risk of developing the disease. A further ten individuals from five families with hereditary non-polyposis colorectal cancer (HNPCC) were also tested. CHRPE was seen in 28 of the 32 affected individuals, 27 of whom met the criteria for a positive examination. Three individuals at risk of FAP also had positive examinations. Five individuals from the families with HNPCC also had CHRPE, although none met the criteria for a positive examination. Of four types of CHRPE analysed, one (small pigmented dots) was found to be more frequent in older family members (P = 0.012), suggesting that this type of lesion may proliferate with age. Compliance with ophthalmic screening was 97 per cent in families with FAP. Using a combined set of diagnostic criteria, CHRPE identified affected individuals with a specificity of at least 94 per cent and a sensitivity of 84 per cent. Results argue for a combined screening programme for FAP of DNA analysis, indirect ophthalmoscopy and bowel examination.

Congenital hypertrophy of the retinal pigment epithelium (CHRPE) in familial colorectal cancer

“…But in some patients with FAP, CHRPE occurs as multiple bilateral lesions. The reported incidence of CHRPE in FAP kindreds ranges from 66 to 92% [6,[10][11][12][13].…”

Gardner's syndrome: Genetic testing and colonoscopy are indicated in adolescents and young adults with cranial osteomas: A case report

“…The diagnostic criteria with the highest specificity/sensitivity for CHRPE include the detection of four small pigmented lesions, or two lesions of which one is large (> 25% of disc surface), using bilateral lens fundoscopic examination [35] . The presence of multiple bilateral lesions appears to be a highly specific marker for FAP (95%-100% specificity) [36] . This makes ophthalmological examination an attractive noninvasive and early diagnostic test for at-risk family members, aside from genetic testing.…”

Congenital hypertrophy of the retinal pigment epithelium and mandibular osteomata as markers in familial colorectal cancer

“…Seven patients with familial colorectal neoplasia had multiple areas of CHRPE compared with one with sporadic disease (P = 0.02) and one control subject (P = Berk et al, 1988;Chapman et al, 1989;Burn et al. 1991;Giardiello et al, 1991;Morton et al, 1992). Not infrequently, normal individuals have one or two areas of CHRPE (Chapman et al, 1989;Burn et al, 1991), and therefore it is thought to be the presence of multiple areas which is of significance.…”

“…The gene for FAP has been localised to 5q21 (Bodmer et al, 1987), and a variety of polymorphic DNA markers are available (Nakamura et al, 1988;Meera Khan et al, 1988;Dunlop et al, 1990Dunlop et al, , 1991 family syndrome. Morton et al (1992) found CHRPE in five of ten individuals who were members of five hereditary nonpolyposis colorectal cancer families, however none of these individuals met the authors' criteria for a positive test. Sondergaard et al (1985) identified multiple mandibular osteomata in 8 of 31 (26%) individuals with familial colorectal cancer, however these individuals were all members of two large families.…”