Which genetic syndrome is characterized by multiple basal cell carcinomas arising in childhood and increased risk of medulloblastoma?

Explanation

## Nevoid Basal Cell Carcinoma Syndrome (Gorlin Syndrome) **Key Point:** Gorlin syndrome (NBCCS) is an autosomal dominant disorder caused by mutations in the PTCH1 gene (patched homolog 1), a tumor suppressor in the hedgehog signaling pathway. It presents with multiple BCCs in childhood and increased risk of medulloblastoma. ### Clinical Features of Gorlin Syndrome | Feature | Details | |---------|----------| | **BCCs** | Hundreds to thousands; onset in childhood/adolescence | | **Medulloblastoma** | 5–10% lifetime risk; most common malignancy in NBCCS | | **Odontogenic keratocysts** | Jaw cysts (60–80% of patients); pathognomonic | | **Skeletal abnormalities** | Bifid ribs, vertebral anomalies, frontal bossing | | **Palmar/plantar pits** | Punctate depressions; early diagnostic sign | | **Other malignancies** | Ovarian fibromas, cardiac fibromas, gastric carcinoma | **High-Yield:** The diagnosis of Gorlin syndrome should be suspected in any patient with: - Multiple BCCs before age 30 - A family history of BCCs or medulloblastoma - Odontogenic keratocysts - Palmar/plantar pits **Mnemonic:** **PTCH1** — Patched 1 gene mutation drives Gorlin syndrome. **GORLIN** — **G**enetic (autosomal dominant), **O**dontogenic keratocysts, **R**ibs (bifid), **L**ips (pits in palms/soles), **I**ncreased BCCs, **N**eoplasms (medulloblastoma). **Clinical Pearl:** Patients with Gorlin syndrome require: - Whole-body skin surveillance every 3–6 months - Annual imaging (MRI brain) for medulloblastoma screening until age 5–8 - Genetic counseling and family screening - Preventive measures: sunscreen, topical retinoids, photodynamic therapy for BCCs