Uveal nevus

Uveal nevus is a flat or minimally elevated, variably pigmented tumor that may occur in the iris (305, 306) or in the choroid (307–309). Although it is most likely to be congenital it is usually asymptomatic and not usually recognized until later in life. Although most uveal nevi are stationary and

nonprogressive, malignant transformation into melanoma can occur in rare instances.78,79

Factors that predict risk of transformation into melanoma are listed in Table 32.

An important variant of iris nevus is the presence of bilateral multiple slightly elevated melanocytic lesions of the iris, known as Lisch nodules. These lesions become clinically

apparent at about age 5 years and are often the first sign of von Recklinghausen’s neurofibromatosis.

Uveal melanoma

Although uveal melanoma is generally a disease of adulthood, it is occasionally diagnosed in children.80 It is a variably pigmented elevated mass that shows slow progression (310). If it is not treated early, it has a tendency to metastasize to liver, lung, and other distant sites. Most advanced tumors are treated by enucleation. Radiotherapy or local tumor resection can be employed for less advanced tumors.

307

307–309 Choroidal freckles and nevi.

307:Flat macular choroidal freckle;

308:slightly thickened suspicious choroidal nevus in macular region;309: very suspicious choroidal nevus versus small melanoma with orange pigment and subretinal fluid.

310 Choroidal melanoma with shallow subretinal fluid and documented growth in a 16-year-old boy.

308

309

310

Congenital hypertrophy of retinal pigment epithelium

Congenital hypertrophy of the retinal pigment epithelium (CHRPE) is a well-circumscribed, flat, pigmented lesion that can occur anywhere in the fundus.81 It often shows depigmented lacunae within the lesion and a surrounding pale halo. It can occur as a solitary lesion or it can be multiple as part of a congenital grouped pigmentation lesion (311, 312). Similar but distinct multifocal pigmented lesions may be a marker for familial adenomatous polyposis and Gardner’s syndrome, in which patients have a high likelihood of developing colonic cancer.

Leukemia

Childhood leukemias can occasionally exhibit tumor infiltration in the retina, optic disc, and uveal tract. Infiltration is characterized by a swollen optic disc and thickening of the retina and choroid, often with hemorrhage and secondary retinal detachment. Intraocular leukemic infiltrates are generally responsive to irradiation and chemotherapy, but they generally portend a poor systemic prognosis.