Basaloid follicular hamartomas in pediatric Basal Cell Nevus Syndrome: A diagnostic challenge.
Ontology highlight
ABSTRACT:
SUBMITTER: Besagni F
PROVIDER: S-EPMC8362058 | biostudies-literature |
REPOSITORIES: biostudies-literature
Similar Datasets
Project description:Basaloid follicular hamartomas (BFH) are benign small basaloid skin tumors that can present as solitary or multiple lesions. Congenital BFH lesions arranged in a segmental distribution have been described, suggesting they derive from a somatic post-zygotic mutational event. Previously, BFH were described in Happle-Tinschert syndrome, which results from a post-zygotic SMO variant and is characterized by segmental BFH with variable involvement of the teeth, skeleton, and central nervous system. Here, we describe two patients with isolated segmental BFH and no systemic involvement. Paired whole exome sequencing of BFH and normal tissue revealed a pathogenic SMO c.1234 C>T, p.L412F variant restricted to BFH tissue. We characterized the proliferation index and expression of Hedgehog and Wnt/beta-catenin pathway related proteins in segmental BFH compared to sporadic basal cell carcinomas (BCCs) and found that segmental BFH had a lower proliferation index. Although segmental BFH expressed a similar level of Gli-1 compared to BCCs, levels of LEF-1 and SOX-9 expression in BFH were weaker for both and patchier for LEF-1. Our results show that a somatic SMO activating variant causes segmental BFH. Since these patients are prone to developing BCCs, differences in SOX9, LEF1, and Ki-67 expression can help distinguish between these two basaloid lesions.
| S-EPMC9669121 | biostudies-literature
Project description:IntroductionNevoid basal cell carcinoma syndrome is a rare autosomal dominant disorder characterized by numerous basal cell carcinomas, odontogenic keratocysts of the jaws and developmental defects. The disorder results from mutations in the PTCH1 gene.Case presentationA 15-year-old boy presented to our dental clinic with multiple jaw cysts. The patient had broad confluent eyebrows, a broad base of the nose, frontal bossing and palmoplantar pits. Examination of the jaw cysts revealed many keratinizing cysts without granular cell layers a finding that raised the suspicion of nevoid basal cell carcinoma. Radiological examinations showed calcification of the falx cerebri, spina bifida, bifid thoracic ribs and frontal bossing. Histopathological examination showed basaloid proliferation in the upper dermis with follicular differentiation surrounded by a loose mucinous stroma and retraction artifacts. These features make it difficult to differentiate between nevoid basal cell carcinoma and basaloid follicular hamartoma, especially the presence of these findings on a non-hairy area. BCL-2 staining was positive in the periphery of the basaloid proliferation, which is typical of basaloid follicular hamartoma, and not in a diffuse pattern, which is typical of nevoid basal cell carcinoma. The proband's siblings and parents were healthy with no family history of this condition in the extended family. Since histology was equivocal and palmoplantar pits are seen in both basaloid follicular hamartoma and nevoid basal cell carcinoma, molecular genetic investigation was necessary to differentiate between the two potential diagnoses. After sequencing the entire PTCH1 gene, we detected a single nucleotide deletion (c.1291delC) in codon 431 of the PTCH protein, which resulted in a premature stop translation at residue 431. This de novo mutation was not detected in both parents and in 100 normal volunteers of matching ethnicity.ConclusionScreening the PTCH1 gene for mutations helped to differentiate between basaloid follicular hamartoma and nevoid basal cell carcinoma and confirmed the diagnosis.
| S-EPMC2642855 | biostudies-literature
Project description: Not available
| S-EPMC5560190 | biostudies-literature
Project description:Basal cell nevus syndrome (BCNS) is an autosomal dominant skin disorder characterized by multiple basal cell nevi. Patients with BCNS tend to develop basal cell carcinoma (BCC) and frequently show skeletal abnormalities. Most cases of BCNS are caused by mutations in patched 1 (PTCH1). PTCH1 encodes a transmembrane receptor protein for the secreted molecule sonic hedgehog, which plays a key role in the development of animals ranging from insects to mammals. We analyzed two Japanese BCNS patients from two independent families. Both of our patients had multiple jaw keratocysts. In one patient, these were the key to noticing his BCNS, as he had no skin tumors. The early detection of PTCH1 mutations would enable BCNS patients to be carefully followed up for the occurrence of BCC. The diagnosis of BCC at the early stage leads to prompt surgical treatments, resulting in a good prognosis. The present cases suggest that keratocysts of the jaw might be an important clue for diagnosing BCNS.
| S-EPMC8236691 | biostudies-literature
Project description:BackgroundDysregulated hedgehog signaling is the pivotal molecular abnormality underlying basal-cell carcinomas. Vismodegib is a new orally administered hedgehog-pathway inhibitor that produces objective responses in locally advanced and metastatic basal-cell carcinomas.MethodsWe tested the anti-basal-cell carcinoma efficacy of vismodegib in a randomized, double-blind, placebo-controlled trial in patients with the basal-cell nevus syndrome at three clinical centers from September 2009 through January 2011. The primary end point was reduction in the incidence of new basal-cell carcinomas that were eligible for surgical resection (surgically eligible) with vismodegib versus placebo after 3 months; secondary end points included reduction in the size of existing basal-cell carcinomas.ResultsIn 41 patients followed for a mean of 8 months (range, 1 to 15) after enrollment, the per-patient rate of new surgically eligible basal-cell carcinomas was lower with vismodegib than with placebo (2 vs. 29 cases per group per year, P<0.001), as was the size (percent change from baseline in the sum of the longest diameter) of existing clinically significant basal-cell carcinomas (-65% vs. -11%, P=0.003). In some patients, all basal-cell carcinomas clinically regressed. No tumors progressed during treatment with vismodegib. Patients receiving vismodegib routinely had grade 1 or 2 adverse events of loss of taste, muscle cramps, hair loss, and weight loss. Overall, 54% of patients (14 of 26) receiving vismodegib discontinued drug treatment owing to adverse events. At 1 month, vismodegib use had reduced the hedgehog target-gene expression by basal-cell carcinoma by 90% (P<0.001) and diminished tumor-cell proliferation, but apoptosis was not affected. No residual basal-cell carcinoma was detectable in 83% of biopsy samples taken from sites of clinically regressed basal-cell carcinomas.ConclusionsVismodegib reduces the basal-cell carcinoma tumor burden and blocks growth of new basal-cell carcinomas in patients with the basal-cell nevus syndrome. The adverse events associated with treatment led to discontinuation in over half of treated patients. (Funded by Genentech and others; ClinicalTrials.gov number, NCT00957229.).
| S-EPMC4362529 | biostudies-literature
Project description:ObjectivesTo evaluate vitamin D status in patients with basal cell nevus syndrome (BCNS) who practice photoprotection because of their genetic predisposition to skin cancer and to determine risk factors for deficiency.DesignRetrospective cohort study.SettingAcademic medical centers.PatientsForty-one ambulatory patients with BCNS who participated in a 2-year chemoprevention clinical trial. Population-based controls (n = 360) were selected and matched by age, sex, Fitzpatrick skin type, and season/geography.Main outcome measuresLevels of 25-hydroxyvitamin D (25[OH]D) and vitamin D deficiency (defined as a 25[OH]D level of ≤20 ng/mL).ResultsTwenty-three patients with BCNS (56%) were vitamin D deficient. Patients with BCNS had mean 25(OH)D levels below those of the general population (-3 ng/mL; P = .02) and were 3 times more likely to be vitamin D deficient (56% vs 18%; P < .001). Levels of 25(OH)D were lower in patients who were overweight (-3.0 ng/mL; P = .04) and who had blood collected in the winter compared with the summer (-7.1 ng/mL; P < .001).ConclusionPatients with BCNS may be at increased risk for vitamin D deficiency, depending on their adherence to photoprotection practices.
| S-EPMC3775573 | biostudies-literature
Project description:AimTo search for patched homologue 1 (PTCH1) mutations in four families with basal cell nevus syndrome (BCNS).MethodsMutation analysis of PTCH1 in unrelated Japanese families affected with BCNS was carried out by direct sequencing.ResultsSix novel PTCH1 mutations, 833G-->A in exon 6, 1415C-->A and 1451G-->T in exon 10, 2798delC in exon 17, 2918-2925dupAGTTCCCT in exon 18 and 3956C-->A in exon 23, were identified.ConclusionsAmong the six PTCH1 mutations, two frameshift mutations (2798delC and 2918-2925dupAGTTCCCT) and one nonsense mutation (833G-->A) are predicted to lead to premature termination of PTCH1 protein translation. Three simultaneous mutations, 1415C-->A (A472D) and 1451G-->T (G484V) in exon 10, and 3956G-->A (R1319H) in exon 23, were found on one allele in only affected members in one family and none of them were found among 90 unrelated healthy Japanese. The three mutations on one chromosome may have resulted from errors in the recombinational repair process and this is the first report on the PTCH1 mutations due to such a mechanism.
| S-EPMC1861741 | biostudies-literature
Project description:Basal cell nevus syndrome (BCNS) is an inherited disorder characterized mainly by the development of basal cell carcinomas (BCCs) at an early age. BCNS is caused by heterozygous small-nucleotide variants (SNVs) and copy-number variants (CNVs) in the Patched1 (PTCH1) gene. Genetic diagnosis may be complicated in mosaic BCNS patients, as accurate SNV and CNV analysis requires high-sensitivity methods due to possible low variant allele frequencies. We compared test outcomes for PTCH1 CNV detection using multiplex ligation-probe amplification (MLPA) and digital droplet PCR (ddPCR) with samples from a BCNS patient heterozygous for a PTCH1 CNV duplication and the patient's father, suspected to have a mosaic form of BCNS. ddPCR detected a significantly increased PTCH1 copy-number ratio in the index patient's blood, and the father's blood and tissues, indicating that the father was postzygotic mosaic and the index patient inherited the CNV from him. MLPA only detected the PTCH1 duplication in the index patient's blood and in hair and saliva from the mosaic father. Our data indicate that ddPCR more accurately detects CNVs, even in low-grade mosaic BCNS patients, which may be missed by MLPA. In general, quantitative ddPCR can be of added value in the genetic diagnosis of mosaic BCNS patients and in estimating the recurrence risk for offspring.
| S-EPMC10886644 | biostudies-literature
Project description:Basal cell nevus syndrome (BCNS) is a rare, multisystem, autosomal dominant disorder that is characterized by various phenotypes, including multiple basal cell carcinomas of the skin, odontogenic keratocysts of the jaws, and occasionally cleft lip and/or palate. In this report, we describe a 6-year-old Japanese girl with a novel heterozygous nonsense mutation in PTCH1 who exhibited rare craniofacial phenotypes, such as oligodontia and a short-tooth root.
| S-EPMC6445144 | biostudies-literature
Project description:ImportanceKeratocystic odontogenic tumors (KCOTs) of the jaw affect more than 65% of patients with basal cell nevus syndrome (BCNS). Surgery frequently causes facial disfigurement and is not always curative. Most BCNS-related and some sporadic KCOTs have malignant activation of the Hedgehog signaling pathway.ObservationsWe examined the effect of vismodegib (an oral Hedgehog pathway inhibitor) on KCOT size in patients with BCNS enrolled in a clinical trial testing vismodegib for basal cell carcinoma prevention (NCT00957229), using pretreatment and posttreatment magnetic resonance imaging. Four men and 2 women had pretreatment KCOTs (mean longest diameter, 2.0 cm; range, 0.7-3.3 cm), occurring primarily in the mandible. Patients were treated with vismodegib, 150 mg/d, for a mean (SD) of 18.0 (4.8) months (range, 11-24 months). Four patients experienced a size reduction and 2 had no change. Vismodegib reduced the mean longest diameter of KCOTs in all patients by 1.0 cm (95% CI, 0.03-1.94; P = .02) or 50% from baseline. We observed no enlargement of existing KCOTs or new KCOT development.Conclusions and relevanceVismodegib shrinks some KCOTs in patients with BCNS and may offer an alternative to surgical therapy. These effects were maintained for at least 9 months after drug cessation in 1 patient. Further studies assessing long-term efficacy and optimal maintenance regimens should be performed.
| S-EPMC4024084 | biostudies-literature