Nevoid basal cell carcinoma syndrome (Gorlin-Goltz syndrome) is caused by mutation in which tumour suppressor gene, and what is the associated intracranial calcification pattern?

• A PTCH1 gene (patched-1); lamellar (falx cerebri) calcification ✓
• B TP53 gene; periventricular calcification
• C RB1 gene; basal ganglia calcification
• D VHL gene; cerebellar calcification

Explanation

Gorlin-Goltz syndrome is caused by germline mutations in PTCH1 (patched homolog-1) on chromosome 9q22, a tumour suppressor in the Sonic Hedgehog signalling pathway. Key features: multiple BCCs before age 20, odontogenic keratocysts of the jaw, bifid ribs, macrocephaly, and calcification of the falx cerebri (lamellar/bridging calcification visible on skull X-ray/CT — nearly pathognomonic). Medulloblastoma (desmoplastic type) occurs in ~5%. Hedgehog pathway inhibitors (vismodegib) are used for advanced/locally aggressive disease.

Reference: Neena Khanna Illustrated Synopsis of Dermatology & STD, 6th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.