ABSTRACT
Clinical findings ● Multiple basal cell carcinomas appearing as smooth, flesh-colored to red-brown papules distributed mainly on the face, neck, back and chest (90%) (Figures 24.1-24.4)
Figure 24.1 ● Palmar and plantar pits 2-3 mm in diameter in 65-80% of patients (Figure 24.5) ● Facial milia and epidermal cysts on the limbs and trunk (-50%) (Figure 24.6) ● Occasionally acrochordons (Figure 24.7)
Extracutaneous manifestations ● Odontogenic cysts of the jaw in about 80% of patients: multiple, often symptomatic,
causing marked tooth displacement ● Calcification of falx cerebri in about 85% of patients ● Musculoskeletal abnormalities: enlarged occipitofrontal circumference (80%), frontal bossing (65%), fused or bifid ribs (50%), spina bifida occulta of cervical or thoracic
(15-45%), cleft palate (5%), polydactyly (4%)
Figure 24.2
Figure 24.3
Figure 24.4
Figure 24.5 ● Eye anomalies in 10-25% of patients: cataract, strabismus, colobomas of iris, choroid
or optic nerve, hypertelorism ● Hypogonadism in 5-10% of male patients
Figure 24.6
Figure 24.7 ● Kidney anomalies (5%): horseshoe kidney, unilateral renal agenesis ● Occasionally, mental retardation and seizures due to cerebellar medulloblastoma in 3-
5% that may be the first manifestation of the disease
● Cardiac fibroma (3%) ● Mesenteric cysts ● Fetal rhabdomyoma, fibrosarcoma, leiomyomas
Course and prognosis
● Basal cell carcinomas may increase in number and become aggressive after puberty ● Odontogenic cysts occur frequently before basal cell carcinomas and may easily recur
after removal ● Musculoskeletal abnormalities may be congenital and medulloblastoma may occasionally be the first manifestation
Laboratory investigations
● Histopathologic findings: typical aspect of basal cell carcinoma or rarely of infundibulocystic basal cell carcinoma
● Skeletal radiography ● Total body magnetic resonance imaging
Genetics and pathogenesis
● Autosomal dominant inheritance ● The responsible gene, the PTCH gene, is mapped to chromosome 9q22.3-q31 ● The PTCH gene is a tumor suppressor gene and patients with mutations in this gene have a predisposition not only for multiple basal cell carcinomas but also for other tumors and skeletal abnormalities
Differential diagnosis
● Bazex syndrome ● Other cancer-related genodermatoses
Follow-up and therapy
● Close surveillance is mandatory, with periodic radiography and nuclear magnetic resonance examinations
● It is necessary to avoid sun exposure and radiotherapy ● Basal cell carcinomas: topical 5-fluorouracil or imiquimod cream, surgical excision,
electrodesiccation, CO2 laser, photodynamic therapy, oral retinoids
Boutet N, Bignon YJ, Drouin-Garraud V, et al. Spectrum of PTCH1 mutations in French patients with Gorlin syndrome. J Invest Dermatol 2003; 121:478-81
Chiritesen E, Maloney ME. Acrochordons as a presenting sign of nevoid basal cell carcinoma syndrome. J Am Acad Dermatol 2001; 44:789-94
Cohen MM Jr. Craniofacial anomalies: clinical and molecular perspectives. Ann Acad Med Singapore 2003; 32:244-51
Gorlin RJ. Nevoid basal cell carcinoma syndrome. Dermatol Clin 1995; 13:113-25 Olivieri C, Maraschio P, Caselli D, et al. Intersitial deletion of chromosome 9, int del(9)
(9q22.31.2), including the genes causing multiple basal cell nevus syndrome and Robinow/ brachydactyly 1 syndrome. Eur J Pediatr 2003; 162:100-3
MUIR-TORRE SYNDROME
Synonym ● Torre syndrome
Age of onset ● Fourth or fifth decade of life
Clinical findings
Skin lesions ● Sebaceous gland tumors (hyperplasias, adenomas, carcinomas) presenting as yellow
papules or nodules located mainly on the face (Figures 24.8-24.10) ● Keratoacanthomas (one or more) spontaneously involuting as associated cutaneous finding (23%)
Extracutaneous features ● Colorectal cancers (53%) ● Colon polyps ● Genitourinary neoplasms (25%) ● Breast and lung tumors ● Hematologic malignancies
Course and prognosis
Visceral malignancies, usually of low grade, may precede the appearance of sebaceous tumors in 60%.
