NBCCS is caused by pathogenic variants in PTCH1 or SUFU. PTCH1 encodes a transmembrane receptor and tumor suppressor in the Hedgehog signaling pathway; loss-of-function variants in PTCH1 result in constitutive activation of Hedgehog signaling, driving uncontrolled proliferation in sensitive tissues. SUFU encodes Suppressor of Fused, another negative regulator of Hedgehog signaling. Both genes follow an autosomal dominant inheritance pattern, consistent with a two-hit tumor suppressor model for tumor development. Genotype-phenotype correlations have been identified for PTCH1: individuals with PTCH1 missense variants are diagnosed later and are less likely to develop ten or more BCCs or jaw keratocysts compared with those harboring other PTCH1 variant types. The distinct SUFU-related phenotype, with higher medulloblastoma risk and lower BCC burden, illustrates the differential downstream consequences of the two genes.

No published consensus diagnostic criteria exist for NBCCS. Proposed criteria classify findings as major or minor. Major criteria include lamellar or sheet-like calcification of the falx, BCCs especially before age 30, jaw keratocysts, a first-degree relative with NBCCS, and bifid or fused ribs. Additional findings include macrocephaly, characteristic facial features, skeletal anomalies, ophthalmologic manifestations, and brain tumors. NBCCS is confirmed by molecular genetic testing identifying a pathogenic variant in PTCH1 or SUFU. Clinical evaluation at diagnosis includes baseline head circumference measurement, ophthalmologic evaluation, and assessment for jaw keratocysts and skeletal anomalies. Evidence of rapid increase in head circumference centiles warrants investigation to exclude hydrocephalus. Brain imaging can detect falx calcification, medulloblastoma, or other intracranial anomalies.

No approved systemic pharmacologic treatments are listed in the packet for NBCCS. Management is multidisciplinary and surveillance-based. BCCs are managed by regular dermatologic monitoring with surgical excision as the standard approach. Jaw keratocysts are managed by enucleation or other surgical interventions. Ophthalmologic evaluation addresses strabismus, cataracts, and orbital cysts. Investigational approaches to BCC treatment include topical aminolevulinic acid combined with photodynamic therapy, topical 5-fluorouracil (effective for superficial multicentric BCCs without follicular involvement), and topical imiquimod. Orphan drug-designated investigational agents include itraconazole and patidegib (a topical Hedgehog pathway inhibitor). The three orphan-designated agents — itraconazole, patidegib, and tin ethyl etiopurpurin — remain investigational and are not approved treatments.

Prognosis in NBCCS is variable and depends on the burden of BCCs, occurrence of medulloblastoma, and severity of jaw keratocyst disease. In SUFU-related NBCCS, medulloblastoma risk in childhood is a significant concern, warranting dedicated surveillance. BCC burden in PTCH1-related disease can be substantial, particularly in individuals with missense variants, though long-term BCC management is feasible with regular surveillance and excision. Jaw keratocyst recurrence after treatment is recognized. The variable expressivity of the syndrome means some individuals with familial NBCCS may have relatively mild phenotypes. Early molecular diagnosis allows targeted surveillance in at-risk family members, facilitating detection of complications before they become clinically advanced.

Five active or recruiting clinical trials are listed for NBCCS. Research is ongoing into Hedgehog pathway inhibition as a targeted strategy for BCCs; patidegib, a topical smoothened inhibitor, is under investigation to reduce BCC formation. Topical treatment modalities including 5-fluorouracil and photodynamic therapy with aminolevulinic acid continue to be evaluated. Genotype-phenotype studies are refining the differential impact of PTCH1 variant types and SUFU variants on clinical outcomes. Epidemiologic studies suggest the true prevalence of NBCCS is likely underestimated due to underdiagnosis of mildly affected individuals, and ongoing registry efforts aim to better characterize the full phenotypic spectrum across both PTCH1 and SUFU variant classes.