Study of Skin Tumors in Tuberous Sclerosis

Patients with tuberous sclerosis develop benign cutaneous tumors that are typically multiple in number and location. These tumors include facial angiofibromas, forehead plaques, shagreen patches, periungual fibromas, and gingival fibromas. The tumors are permanent, slow growing, and often disfiguring. The purpose of this study is to elucidate the molecular basis for these tumors. Specifically, we plan to identify the genetically altered cells in these hamartomatous lesions, and to quantify factors (e.g. cytokines) produced by these cells which induce the growth of these tumors. To accomplish this, we plan to obtain samples of these cutaneous tumors, to test tumor DNA for loss of heterozygosity, and to measure RNA and protein expression levels.

• INCLUSION CRITERIA:

Patients will be those already diagnosed with TSC (definite, probable, or possible) based on clinical criteria and/or genetic testing, and ranging in age from 18 to 90 years old.

The clinical features of TSC considered of major significance are: facial angiofibromas or forehead plaque, nontraumatic periungual fibromas, three or more hypomelanotic macules, shagreen patch, multiple retinal nodular hamartomas, cortical tuber, subependymal nodule, subependymal giant cell astrocytoma, cardiac rhabdomyoma, lymphangioleiomyomatosis, and renal angiomyolipoma.

The minor features of TSC are: multiple randomly distributed pits in dental enamel, hamartomatous rectal polyps, bone cysts, cerebral white matter radial migration lines, gingival fibromas, nonrenal hamartoma, retinal achromic patch, confetti skin lesions, and multiple renal cysts (5). Definite TSC is diagnosed by the presence of two major features or one major feature plus two minor features. Probable TSC is diagnosed by the presence of one major feature and one minor feature. Possible TSC is diagnosed by the presence of either one major feature or two or more minor features. Patients will not be preselected for skin lesions, but about 80% of patients with TSC are expected to have skin lesions.

Exclusion criteria

Inability to give informed consent.

Tendency to keloid formation.

Allergy to anesthetics.

Bleeding abnormality.