Nevoid Basal Cell Carcinoma (Gorlin-Goltz) Syndrome

Aka basal cell nevus syndrome

Epidemiology and Etiology:

· Autosomal dominant

· Most tumours develop before age 20 usually

· PTCH gene (9q22.3)

· Germline mutation of one allele

· Same gene is mutated in sporadic BCC

· Encodes receptor for SHH (sonic hedgehog gene) product

· Determines polarity during development

· In absence of SHH, PTCH normally binds with SMO (smoothened, another transmembrane protein) and inactivates it

· Binding of SHH to PTCH disinhibits SMO which then upregulates hedgehog target genes via GLI1 transcription factor

Common sites:

· Skin

· Multiple basal cell carcinomas

· CNS

· Medulloblastoma

· Intracranial calcification

· Ovary

· Fibroma

· Oral cavity

· Odontogenic keratocyst

· Cleft lip and palate

· Palms and soles

· Pits

· Bones

· Abnormal segmentation of vertebra

· Rib abnormalities (bifid, fused, missing, splayed)

Gross features:

·

Histologic features:

·

Immunophenotype:

Marker:

Sensitivity:

Specificity:

Molecular features:

·

Other features:

· Generalized overgrowth

References:

· Kumar V, Fausto N, Abbas A. Robbins & Cotran Pathologic Basis of Disease, Seventh Edition. 7th ed. Saunders; 2004.