Basaloid follicular hamartomas in pediatric Basal Cell Nevus Syndrome: A diagnostic challenge

Abstract

Basal Cell Nevus Syndrome (BCNS) is an autosomal dominant inherited disease caused by PTCH1 (9q22.3‐q31) germline mutations. Skin manifestations are mainly characterized by hyperkeratosis of the palms and soles, palmoplantar pits and a strong predisposition to develop multiple basal cell carcinomas (BCCs). Recently, it has been hypothesized that basaloid follicular hamartomas (BFH) could be included in BCNS skin features. We present three pediatric cases of GS with BCCs and BFHs. Clinical, dermoscopic and immunohistochemical tools are reported.

When to suspect a supressor of fused homolog (SUFU)‐associated basal cell nevus syndrome

“…Basal cell nevus syndrome (BCNS), also known as Gorlin syndrome (GS), is a tumor predisposing disorder with an autosomal dominant inheritance 1,2 . It is caused by mutations in the hedgehog pathway, being PTCH1 the most commonly affected gene.…”

Basal cell carcinomas acquire secondary mutations to overcome dormancy and progress from microscopic to macroscopic disease

“…In addition, TP53 mutations are present in ~40% of Gorlin BCCs, similar to sporadic tumors ( Chiang et al, 2018 ). Finally, Gorlin BCCs can manifest a variety of histologic subtypes ( Rehefeldt-Erne et al, 2016 ), and Gorlin patients can also develop basaloid follicular hamartoma (BFH), a benign hair follicle tumor ( Besagni et al, 2021 ; Chikeka et al, 2021 ; Ponti et al, 2018 ; Requena and Sangueza, 2017 ). While the connection between BFH and BCC remains unclear, some have speculated that these neoplasms are variations of the same disease ( Ponti et al, 2018 ).…”

Patient and caregiver perspectives on delayed childhood Gorlin syndrome diagnoses

“…The detailed relationship between presenting signs and diagnostic delays cannot be ascertained from this anonymous survey as it is not corroborated by medical records. Some presenting signs that could influence earlier diagnosis are not captured in this survey; for example, the distinction between basaloid follicular hamartomas and BCC is not made 9 and would be challenging for patients to reliably report. In addition, histopathologic features of tumors that may increase suspicion of GS (i.e., infundibuloblastic differentiation) 10 are unknown.…”