First evidence of genotype-phenotype correlations in Gorlin syndrome

Medulloblastoma and other neoplasms in patients with heterozygous germline SUFU variants: A scoping review

In 2002, heterozygous suppressor of fused variants (SUFU+/-) in the germline were described to have a tumor suppressor role in the development of pediatric medulloblastoma (MB). Other neoplasms associated with pathologic germline SUFU+/- variants have also been described among patients with basal cell nevus syndrome (BCNS; BCNS is also known as Gorlin syndrome, nevoid basal cell carcinoma [BCC] syndrome or Gorlin-Goltz syndrome; OMIM 109400), an autosomal-dominant cancer predisposition syndrome. The phenotype of patients with germline SUFU+/- variants is very poorly characterized due to a paucity of large studies with long-term follow-up. As such, there is a clinical need to better characterize the spectrum of neoplasms among patients with germline SUFU+/- variants so that clinicians can provide accurate counseling and optimize tumor surveillance strategies. The objective of this study is to perform a scoping review to map the evidence on the rate of medulloblastoma and to describe the spectrum of other neoplasms among patients with germline SUFU+/- variants. A review of all published literature in PubMed (MEDLINE), EMBASE, Cochrane, and Web of Science were searched from the beginning of each respective database until October 9, 2021. Studies of pediatric and adult patients with a confirmed germline SUFU+/- variant who were evaluated for the presence of any neoplasm (benign or malignant) were included. There were 176 patients (N = 30 studies) identified with a confirmed germline SUFU+/- variant who met inclusion criteria. Data were extracted from two cohort studies, two case-control studies, 18 case series, and eight case reports. The median age at diagnosis of a germline SUFU+/- variant was 4.5 years where 44.4% identified as female and 13.4% of variants were de novo. There were 34 different neoplasms (benign and malignant) documented among patients with confirmed germline SUFU+/- variants, and the most common were medulloblastoma (N = 59 patients), BCC (N = 21 patients), and meningioma (N = 19 patients). The median age at medulloblastoma diagnosis was 1.42 years (range 0.083-3; interquartile range 1.2). When data were available for these three most frequent neoplasms (N = 95 patients), 31 patients (32.6%) had neither MB, BCC nor meningioma; 51 patients (53.7%) had one of medulloblastoma or BCC or meningioma; eight patients (8.4%) had two of medulloblastoma or BCC or meningioma, and five patients (5.3%) had medulloblastoma and BCC and meningioma. This is the first study to synthesize the data on the frequency and spectrum of neoplasms specifically among patients with a confirmed germline SUFU+/- variant. This scoping review is a necessary step forward in optimizing evidence-based tumor surveillance strategies for medulloblastoma and estimating the risk of other neoplasms that could impact patient outcomes.

European consensus-based interdisciplinary guideline for diagnosis and treatment of basal cell carcinoma-update 2023

Basal cell carcinoma (BCC) is the most common malignant tumour in white populations. Multidisciplinary experts from European Association of Dermato-Oncology (EADO), European Dermatology Forum, European Society for Radiotherapy and Oncology (ESTRO), Union Européenne des Médecins Spécialistes, and the European Academy of Dermatology and Venereology developed updated recommendations on diagnosis and treatment of BCC. BCCs were categorised into 'easy-to-treat' (common) and 'difficult-to-treat' according to the new EADO clinical classification. Diagnosis is based on clinico-dermatoscopic features, although histopathological confirmation is mandatory in equivocal lesions. The first-line treatment of BCC is complete surgery. Micrographically controlled surgery shall be offered in high-risk and recurrent BCC, and BCC located on critical anatomical sites. Topical therapies and destructive approaches can be considered in patients with low-risk superficial BCC. Photodynamic therapy is an effective treatment for superficial and low-risk nodular BCCs. Management of 'difficult-to-treat' BCCs should be discussed by a multidisciplinary tumour board. Hedgehog inhibitors (HHIs), vismodegib or sonidegib, should be offered to patients with locally advanced and metastatic BCC. Immunotherapy with anti-PD1 antibodies (cemiplimab) is a second-line treatment in patients with a progression of disease, contraindication, or intolerance to HHI therapy. Radiotherapy represents a valid alternative in patients who are not candidates for or decline surgery, especially elderly patients. Electrochemotherapy may be offered when surgery or radiotherapy is contraindicated. In Gorlin patients, regular skin examinations are required to diagnose and treat BCCs at an early stage. Long-term follow-up is recommended in patients with high-risk BCC, multiple BCCs, and Gorlin syndrome.

Advances in the systemic therapy for recurrent meningiomas and the challenges ahead

INTRODUCTION

Meningiomas represent the most common primary neoplasms of the central nervous system (CNS). 20% present with atypical (WHO grade II) or malignant (grade III) meningiomas, which show aggressive biologic behavior and high recurrence. Although surgical resection and radiation therapy are the primary treatment options for these tumors, there is a subgroup of patients who do not respond well to or are poor candidates for these approaches, leading to the exploration of systemic therapies as an alternative.

AREAS COVERED

The literature on different therapeutic groups of systemic drugs for recurrent meningiomas is reviewed, with a focus on the different molecular targets. Past and current ongoing clinical trials are also discussed.

EXPERT OPINION

To date, there is no recognized treatment that has demonstrated a substantial increase in progression-free or overall survival rates. Nonetheless, therapies targeting anti-VEGF have exhibited more encouraging results in general. The examination of genomic and epigenomic traits of meningiomas, along with the integration of molecular markers into the latest WHO tumor grading system, has provided valuable insights. This has opened avenues for exploring numerous intracellular and extracellular pathways, as well as mutations, that have been targeted in ongoing clinical trials.

Update on Ovarian Sex Cord-Stromal Tumors

This article focuses on the recent advances in ovarian sex cord-stromal tumors, predominantly in the setting of their molecular underpinnings. The integration of genetic information with morphologic and immunohistochemical findings in this rare subset of tumors is of clinical significance from refining the diagnostic and prognostic stratifications to genetic counseling.

Congenital medulloblastoma in two brothers with SUFU-mutated Gorlin-Goltz syndrome: Case reports and literature review

Background

Congenital medulloblastoma is very rare, and many cases involve germline mutations that can lead to inherited syndromes. Here, we first report two brothers with congenital medulloblastoma who were diagnosed with Gorlin-Goltz syndrome caused by SUFU mutation.

Clinical presentation

Medulloblastoma was detected in two brothers at 2 and 3 months of age, with very similar imaging features. Genetic testing revealed that both children and their mother carried SUFU gene germline mutations, and both brothers were diagnosed with Gorlin-Goltz syndrome.

Conclusion

Gorlin-Goltz syndrome-associated congenital medulloblastoma with SUFU germline mutation is very rare. Pathological types mostly involve desmoplastic/nodular or extensive nodularity; chemotherapy is the main treatment, and studies revealing prognostic data are scarce.

Molecular mechanism of extracutaneous tumours in patients with basal cell nevus syndrome

Basal cell nevus syndrome (BCNS) is a rare genetic disorder accompanied by a broad variety of tumours, of which basal cell carcinomas and odontogenic keratocysts are the most common. BCNS is caused by a germline or postzygotic mutation in either PTCH1 or SUFU As BCNS is a rare disease, it is difficult to establish whether less frequently occurring tumours are actually part of the syndrome. In this study, the molecular mechanism behind four extracutaneous tumours in patients with BCNS was elucidated. A leiomyoma of the testis and meningioma were confirmed to be associated with BCNS in two patients by presence of a second mutation or loss of heterozygosity in PTCH1 In a meningioma of a patient with a mosaic postzygotic PTCH1 mutation an association could not be conclusively confirmed. SUFU was probably not involved in the development of a thyroid carcinoma in a patient with a germline SUFU mutation. Hence, we have proven that meningioma and leiomyoma of the testis are rare extracutaneous tumours that are part of BCNS.

Multidisciplinary approach to Gorlin-Goltz syndrome: from diagnosis to surgical treatment of jawbones

Background

Gorlin syndrome, also known as Gorlin-Goltz syndrome (GGS) or basal cell nevus syndrome (BCNS) or nevoid basal cell carcinoma syndrome (NBCCS), is an autosomal dominant familial cancer syndrome. It is characterized by the presence of numerous basal cell carcinomas (BCCs), along with skeletal, ophthalmic, and neurological abnormalities. It is essential to anticipate the diagnosis by identifying the pathology through the available diagnostic tests, clinical signs, and radiological manifestations, setting up an adequate treatment plan.

Main body

In the first part, we searched recent databases including MEDLINE (PubMed), Embase, and the Cochrane Library by analyzing the etiopathogenesis of the disease, identifying the genetic alterations underlying them. Subsequently, we defined what are, to date, the major and minor clinical diagnostic criteria, the possible genetic tests to be performed, and the pathologies with which to perform differential diagnosis. The radiological investigations were reviewed based on the most recent literature, and in the second part, we performed a review regarding the existing jawbone protocols, treating simple enucleation, enucleation with bone curettage in association or not with topical use of cytotoxic chemicals, and “en bloc” resection followed by possible bone reconstruction, marsupialization, decompression, and cryotherapy.

Conclusion

To promote the most efficient and accurate management of GGS, this article summarizes the clinical features of the disease, pathogenesis, diagnostic criteria, differential diagnosis, and surgical protocols. To arrive at an early diagnosis of the syndrome, it would be advisable to perform radiographic and clinical examinations from the young age of the patient. The management of the patient with GGS requires a multidisciplinary approach ensuring an adequate quality of life and effective treatment of symptoms.

Leiomyomatosis in an Infant With a SUFU Splice Site Variant: Case Report

Heterozygous loss-of-function variants in the suppressor of fused protein gene (SUFU) can result in Gorlin syndrome, which is characterized by an increased frequency of basal cell carcinoma, medulloblastoma, odontogenic keratocysts, as well as other tumors. We describe a case of a 5-month-old female who presented with multiple intra-abdominal leiomyomata and was found to have a likely pathogenic splice site variant in the SUFU gene. This is the first reported case of leiomyomatosis secondary to a pathogenic SUFU variant in an infant and may represent an early, atypical presentation of Gorlin syndrome.

Cancer risk and tumour spectrum in 172 patients with a germline SUFU pathogenic variation: a collaborative study of the SIOPE Host Genome Working Group

BACKGROUND

Little is known about risks associated with germline SUFU pathogenic variants (PVs) known as a cancer predisposition syndrome.

METHODS

To study tumour risks, we have analysed data of a large cohort of 45 unpublished patients with a germline SUFU PV completed with 127 previously published patients. To reduce the ascertainment bias due to index patient selection, the risk of tumours was evaluated in relatives with SUFU PV (89 patients) using the Nelson-Aalen estimator.

RESULTS

Overall, 117/172 (68%) SUFU PV carriers developed at least one tumour: medulloblastoma (MB) (86 patients), basal cell carcinoma (BCC) (25 patients), meningioma (20 patients) and gonadal tumours (11 patients). Thirty-three of them (28%) had multiple tumours. Median age at diagnosis of MB, gonadal tumour, first BCC and first meningioma were 1.5, 14, 40 and 44 years, respectively. Follow-up data were available for 160 patients (137 remained alive and 23 died). The cumulative incidence of tumours in relatives was 14.4% (95% CI 6.8 to 21.4), 18.2% (95% CI 9.7 to 25.9) and 44.1% (95% CI 29.7 to 55.5) at the age of 5, 20 and 50 years, respectively. The cumulative risk of an MB, gonadal tumour, BCC and meningioma at age 50 years was: 13.3% (95% CI 6 to 20.1), 4.6% (95% CI 0 to 9.7), 28.5% (95% CI 13.4 to 40.9) and 5.2% (95% CI 0 to 12), respectively. Sixty-four different PVs were reported across the entire SUFU gene and inherited in 73% of cases in which inheritance could be evaluated.

CONCLUSION

Germline SUFU PV carriers have a life-long increased risk of tumours with a spectrum dominated by MB before the age of 5, gonadal tumours during adolescence and BCC and meningioma in adulthood, justifying fine-tuned surveillance programmes.

Update on Ovarian Sex Cord-Stromal Tumors

This article focuses on the recent advances in ovarian sex cord-stromal tumors, predominantly in the setting of their molecular underpinnings. The integration of genetic information with morphologic and immunohistochemical findings in this rare subset of tumors is of clinical significance from refining the diagnostic and prognostic stratifications to genetic counseling.

Gorlin Syndrome: Assessing Genotype-Phenotype Correlations and Analysis of Early Clinical Characteristics as Risk Factors for Disease Severity

PURPOSE

Gorlin syndrome (GS) is a rare genetic disorder characterized by lifetime risk of basal cell carcinomas (BCCs), skeletal anomalies (SAs), and other extracutaneous neoplasms. There is great variation in disease severity, and a genotype-phenotype correlation has not been well established. Here, we investigate whether patients' clinical characteristics predict disease severity to inform clinical decision making.

METHODS

Data of 248 patients with GS were collected between 2014 and 2021 from three institutions. Multivariable regression analyses were performed to investigate whether clinical characteristics predicted disease burden. Genotype-phenotype correlations were investigated in 40 patients.

RESULTS

Patients with SAs had a mean increase of 120 lifetime BCCs (95% CI, 27.1 to 213) relative to patients without SAs. Those with ≥ 2 SAs had 2.45 increased odds (95% CI, 1.01 to 5.91) of advanced or metastatic BCCs. Moreover, the presence of multiple SAs was associated with 5.00 increased odds of having a keratocystic odontogenic tumor (95% CI, 2.22 to 11.3) and 2.79 increased odds of an ovarian fibroma (95% CI, 1.05 to 7.40). Genotype-phenotype analyses showed that missense/in-frame mutations were more likely to be hereditary compared with severe deleterious mutation types (100% v 27%; P = .004). In addition, heat map visualization illustrated that those with more deleterious variants, like large deletions, trended toward increased burden of SAs and BCCs per year.

CONCLUSION

GS patients with SAs may be at greater risk for developing more numerous and severe BCCs and other neoplastic growths including keratocystic odontogenic tumors and ovarian fibromas. Current clinical guidelines suggest yearly follow-up in individuals with GS. Since SAs are usually recognized at the time of diagnosis, our results suggest that more vigilant lifetime multidisciplinary surveillance should be considered for these patients starting in childhood.

Hereditary gynecologic tumors and precision cancer medicine

Gynecologic cancers are more often caused by genetic factors than other cancers. Genetic testing has become a promising avenue for the prevention, prognosis, and treatment of cancers. This review describes molecular features of gynecologic tumors linked to hereditary syndromes, gives an overview of the current state of clinical management, and clarifies the role of gynecology in the treatment of hereditary tumors. Typical hereditary gynecologic tumors include hereditary breast and ovarian cancer, Lynch syndrome, Peutz-Jeghers syndrome, and Cowden syndrome. Multigene panel testing, which analyzes a preselected subset of genes for genetic variants, has recently become the first-choice test because it can provide more accurate risk assessment than a single test. Furthermore, comprehensive genomic cancer profiling enables personalized cancer treatment and aids in germline findings.

Bilateral ovarian fibromas in a 15-year-old primary amenorrhea patient: a case report

A 15-year-old female with primary amenorrhea, obesity, and insulin resistance, was admitted for further examination due to large pelvic masses found during a transabdominal ultrasound, which was performed while assessing the amenorrhea. The magnetic resonance imaging showed bilateral, multifocal fibrosing tumors, originating from both ovaries. A laparotomy was performed, during which the right ovary masses were enucleated and the left adnexectomy was performed. A histological examination of the tissue material revealed bilateral ovarian fibromas with calcification and ossification. The genetic examination confirmed the diagnosis of Gorlin syndrome. The patient recovered well, and on the first follow-up 1 month after surgery, already experienced her first spontaneous menstrual bleeding.

Nevoid basal cell carcinoma syndrome: a case report and literature review

BACKGROUND

Nevoid basal cell carcinoma syndrome (NBCCS) is a rare genetic disorder associated with basal cell carcinomas (BCC), skeletal anomalies, and jaw cysts, and a number of ocular abnormalities. We describe a case of a 12-year-old boy diagnosed with NBCCS found to have several ophthalmic manifestations including a myelinated retinal nerve fiber. We conducted a literature review targeting the ocular and systemic manifestations of NBCCS, with a focus on the ophthalmic findings that have not been well characterized.

MATERIALS AND METHODS

We conducted a literature search from 1960 to 2021 utilizing specific keywords and criteria and excluded non-clinical articles. A total of 46 articles were ultimately used for the literature review.

RESULTS

In NBCCS, BCCs typically present before the age of 30 and gradually become numerous. Certain ocular features, less common in the general population, are much more common with NBCCS. Depending on the study, prevalence of these features in patients with NBCCS ranges from 26-80% for hypertelorism and 7-36% for myelinated retinal nerve fiber layer. Prevalence of nystagmus in patients with NBCCS was found to be approximately 6%. Systemic findings such as bilamellar calcification of the falx cerebri, palmar pits, and odontogenic keratocysts (OKCs) are also prevalent.

CONCLUSION

NBCCS may affect numerous organ systems, and thus requires a multidisciplinary team to manage. BCCs and jaw cysts are commonly occurring clinical features that have various surgical excisional options. The ocular anomalies of NBCCS are individually rare, and certain anomalies may present in the amblyogenic period of development and contribute to visual impairment.

Proposed criteria for nevoid basal cell carcinoma syndrome in children assessed using statistical optimization

Nevoid basal cell carcinoma syndrome (NBCCS) is a tumor predisposition condition, the cardinal features of which emerge in adolescence or adulthood. Using statistical optimization, this study proposes NBCCS criteria with improved sensitivity in children less than 18 years of age. Earlier detection may lead to improved surveillance and prevention of sequelae. A survey eliciting medical history was completed by, or on behalf of, individuals with NBCCS. Based on these findings, criteria for suspicion of NBCCS in children were suggested using information from a Bernoulli naïve Bayes classifier relying on the human phenotype ontology. The sensitivity and specificity of the existing and proposed diagnostic criteria were also assessed. Participants (n = 48) reported their first signs of NBCCS appeared at a median age of 8 months, but by our retrospective analysis, they did not fulfill the current diagnostic criteria until a median age of 7 years. This study delineates the early-onset features of NBCCS and proposes criteria that should prompt consideration of NBCCS. Additionally, we demonstrate a method for quantitatively assessing the utility of diagnostic criteria for genetic disorders.

Basal cell nevus syndrome: an update on clinical findings

Basal cell nevus syndrome, also known as Gorlin-Goltz syndrome, is a rare autosomal dominant disorder caused by mutations in the hedgehog signaling pathway, mainly in PTCH1. This pathway is involved in embryogenesis and tumorigenesis, and the loss of function of PTCH1 protein produces an aberrant increase in the hedgehog signaling pathway activity. Basal cell nevus syndrome is characterized by tumor predisposition, particularly with the development of multiple basal cell carcinomas at an early age, along with odontogenic keratocysts, palmoplantar pits, skeletal abnormalities, and an increased risk of medulloblastoma. Diagnosis is clinical, with gene mutation analysis confirming the suspicion. The striking phenotypic variability of the syndrome may lead to a delayed diagnosis, making it an uncommon but important entity to recognize. A high index of suspicion and an early diagnosis is crucial for prevention, surveillance, and the prompt establishment of multidisciplinary medical care.

A guideline for the clinical management of basal cell nevus syndrome (Gorlin-Goltz syndrome)

The overall objective of this guideline is to provide up-to-date, evidence-based recommendations for the diagnosis and surveillance of all symptoms of children and adults with either basal cell nevus syndrome (BCNS), a clinical suspicion of BCNS, or a parent with BCNS. In the last two groups the guidelines should be followed until the diagnosis of BCNS can be rejected with certainty. The guideline aims to: - Update and expand on the previous guidelines by an appraisal of all relevant literature from January 2011 up to January 2021 - Address important, practical, clinical questions relating to the primary guideline objective - Provide guideline recommendations - Discuss potential developments and future directions.

Review of the Molecular Genetics of Basal Cell Carcinoma; Inherited Susceptibility, Somatic Mutations, and Targeted Therapeutics

Simple Summary

Basal cell carcinoma is the most common human cancer worldwide. The molecular basis of BCC involves an interplay of inherited genetic susceptibility and somatic mutations, commonly induced by exposure to UV radiation. In this review, we outline the currently known germline and somatic mutations implicated in the pathogenesis of BCC with particular attention paid toward affected molecular pathways. We also discuss polymorphisms and associated phenotypic traits in addition to active areas of BCC research. We finally provide a brief overview of existing non-surgical treatments and emerging targeted therapeutics for BCC such as Hedgehog pathway inhibitors, immune modulators, and histone deacetylase inhibitors.

Abstract

Basal cell carcinoma (BCC) is a significant public health concern, with more than 3 million cases occurring each year in the United States, and with an increasing incidence. The molecular basis of BCC is complex, involving an interplay of inherited genetic susceptibility, including single nucleotide polymorphisms and genetic syndromes, and sporadic somatic mutations, often induced by carcinogenic exposure to UV radiation. This review outlines the currently known germline and somatic mutations implicated in the pathogenesis of BCC, including the key molecular pathways affected by these mutations, which drive oncogenesis. With advances in next generation sequencing and our understanding of the molecular genetics of BCC, established and emerging targeted therapeutics are offering new avenues for the non-surgical treatment of BCC. These agents, including Hedgehog pathway inhibitors, immune modulators, and histone deacetylase inhibitors, will also be discussed.

PTCH2 is not a strong candidate gene for gorlin syndrome predisposition

A number of case/family reports have proposed PTCH2 as a putative Gorlin Syndrome (GS) gene, but evidence to support this is lacking. We assessed our cohort of 21 PTCH1/SUFU negative GS families for PTCH2 variants and assessed current evidence from reported cases/families and population data. In our PTCH1/SUFU variant negative GS cohort (25% of total), no pathogenic or likely pathogenic PTCH2 variants were identified. In addition, none of the previously published PTCH2 variants in GS families/cases could be considered pathogenic or likely pathogenic using current guidelines. The absence of clear pathogenic variants in GS families and the high frequency of Loss-of-function (LoF) variants in the general population, including the presence of homozygous LoF variants without a clinical phenotype, mean that it is untenable that PTCH2 is a GS gene. PTCH2 should not be included in panels for genetic diagnosis of GS.

Microdeletion of 9q22.3: A patient with minimal deletion size associated with a severe phenotype

Basal cell nevus syndrome (also known as Gorlin Syndrome; MIM109400) is an autosomal dominant disorder characterized by recurrent pathological features such as basal cell carcinomas and odontogenic keratocysts as well as skeletal abnormalities. Most affected individuals have point mutations or small insertions or deletions within the PTCH1 gene on human chromosome 9, but there are some cases with more extensive deletion of the region, usually including the neighboring FANCC and/or ERCC6L2 genes. We report a 16‐year‐old patient with a deletion of approximately 400,000 bases which removes only PTCH1 and some non‐coding RNA genes but leaves FANCC and ERCC6L2 intact. In spite of the small amount of DNA for which he is haploid, his phenotype is more extreme than many individuals with longer deletions in the region. This includes early presentation with a large number of basal cell nevi and other skin lesions, multiple jaw keratocysts, and macrosomia. We found that the deletion was in the paternal chromosome, in common with other macrosomia cases. Using public databases, we have examined possible interactions between sequences within and outside the deletion and speculate that a regulatory relationship exists with flanking genes, which is unbalanced by the deletion, resulting in abnormal activation or repression of the target genes and hence the severity of the phenotype.

Current recommendations for cancer surveillance in Gorlin syndrome: a report from the SIOPE host genome working group (SIOPE HGWG)

Gorlin syndrome (MIM 109,400), a cancer predisposition syndrome related to a constitutional pathogenic variation (PV) of a gene in the Sonic Hedgehog pathway (PTCH1 or SUFU), is associated with a broad spectrum of benign and malignant tumors. Basal cell carcinomas (BCC), odontogenic keratocysts and medulloblastomas are the main tumor types encountered, but meningiomas, ovarian or cardiac fibromas and sarcomas have also been described. The clinical features and tumor risks are different depending on the causative gene. Due to the rarity of this condition, there is little data on phenotype-genotype correlations. This report summarizes genotype-based recommendations for screening patients with PTCH1 and SUFU-related Gorlin syndrome, discussed during a workshop of the Host Genome Working Group of the European branch of the International Society of Pediatric Oncology (SIOPE HGWG) held in January 2020. In order to allow early detection of BCC, dermatologic examination should start at age 10 in PTCH1, and at age 20 in SUFU PV carriers. Odontogenic keratocyst screening, based on odontologic examination, should begin at age 2 with annual orthopantogram beginning around age 8 for PTCH1 PV carriers only. For medulloblastomas, repeated brain MRI from birth to 5 years should be proposed for SUFU PV carriers only. Brain MRI for meningiomas and pelvic ultrasound for ovarian fibromas should be offered to both PTCH1 and SUFU PV carriers. Follow-up of patients treated with radiotherapy should be prolonged and thorough because of the risk of secondary malignancies. Prospective evaluation of evidence of the effectiveness of these surveillance recommendations is required.

Meningioma: A Review of Epidemiology, Pathology, Diagnosis, Treatment, and Future Directions

Meningiomas are the most common intracranial tumor, making up more than a third of all primary central nervous system (CNS) tumors. They are mostly benign tumors that can be observed or preferentially treated with gross total resection that provides good outcomes. Meningiomas with complicated histology or in compromising locations has proved to be a challenge in treating and predicting prognostic outcomes. Advances in genomics and molecular characteristics of meningiomas have uncovered potential use for more accurate grading and prediction of prognosis and recurrence. With the study and detection of genomic aberrancies, specific biologic targets are now being trialed for possible management of meningiomas that are not responsive to standard surgery and radiotherapy treatment. This review summarizes current epidemiology, etiology, molecular characteristics, diagnosis, treatments, and current treatment trials.

Diagnostic Approach to Macrocephaly in Children

Macrocephaly affects up to 5% of the pediatric population and is defined as an abnormally large head with an occipitofrontal circumference (OFC) >2 standard deviations (SD) above the mean for a given age and sex. Taking into account that about 2-3% of the healthy population has an OFC between 2 and 3 SD, macrocephaly is considered as "clinically relevant" when OFC is above 3 SD. This implies the urgent need for a diagnostic workflow to use in the clinical setting to dissect the several causes of increased OFC, from the benign form of familial macrocephaly and the Benign enlargement of subarachnoid spaces (BESS) to many pathological conditions, including genetic disorders. Moreover, macrocephaly should be differentiated by megalencephaly (MEG), which refers exclusively to brain overgrowth, exceeding twice the SD (3SD-"clinically relevant" megalencephaly). While macrocephaly can be isolated and benign or may be the first indication of an underlying congenital, genetic, or acquired disorder, megalencephaly is most likely due to a genetic cause. Apart from the head size evaluation, a detailed family and personal history, neuroimaging, and a careful clinical evaluation are crucial to reach the correct diagnosis. In this review, we seek to underline the clinical aspects of macrocephaly and megalencephaly, emphasizing the main differential diagnosis with a major focus on common genetic disorders. We thus provide a clinico-radiological algorithm to guide pediatricians in the assessment of children with macrocephaly.

Meningiomas from a developmental perspective: exploring the crossroads between meningeal embryology and tumorigenesis

Meningiomas are tumors arising from the meninges and represent the most frequent central nervous system tumors in adults. Recent large-scale genetic studies and preclinical meningioma mouse modelling led to a better comprehension of meningioma development and suggested evidences of close relationships between meningeal embryology and tumorigenesis. In this non-systematic review, we summarize the current knowledge on meningeal embryology and developmental biology, and illustrate how meningioma tumorigenesis is deeply related to meningeal embryology, concerning the potential cell of origin, the role of reactivation of embryonic stem cells, the influence of the embryonic tissue of origin, and the parallelism between topography-dependant molecular pathways involved in normal meninges and in meningioma development. Our study emphasizes why future studies on meningeal embryology are mandatory to affine our comprehension of mechanisms underlying meningioma initiation and development.

Gorlin Syndrome: Recent Advances in Genetic Testing and Molecular and Cellular Biological Research

Gorlin syndrome is a skeletal disorder caused by a gain of function mutation in Hedgehog (Hh) signaling. The Hh family comprises of many signaling mediators, which, through complex mechanisms, play several important roles in various stages of development. The Hh information pathway is essential for bone tissue development. It is also the major driver gene in the development of basal cell carcinoma and medulloblastoma. In this review, we first present the recent advances in Gorlin syndrome research, in particular, the signaling mediators of the Hh pathway and their functions at the genetic level. Then, we discuss the phenotypes of mutant mice and Hh signaling-related molecules in humans revealed by studies using induced pluripotent stem cells.

Biallelic PTCH1 Inactivation Is a Dominant Genomic Change in Sporadic Keratocystic Odontogenic Tumors

Keratocystic odontogenic tumors (KCOTs) are locally aggressive odontogenic neoplasms with recurrence rates of up to 60%. Approximately 5% of KCOTs are associated with nevoid basal cell carcinoma (Gorlin) syndrome and 90% of these show genomic inactivation of the PTCH1 gene encoding Patched 1. Sporadic KCOTs reportedly have PTCH1 mutations in 30% of cases, but previous genomic analyses have been limited by low tumor DNA yield. The aim of this study was to identify recurrent genomic aberrations in sporadic KCOTs using a next-generation sequencing panel with complete exonic coverage of sonic hedgehog (SHH) pathway members PTCH1, SMO, SUFU, GLI1, and GLI2. Included were 44 sporadic KCOTs from 23 female and 21 male patients with a median age of 50 years (range, 10 to 82 y) and located in the mandible (N=33) or maxilla (N=11). Sequencing identified PTCH1 inactivating mutations in 41/44 (93%) cases, with biallelic inactivation in 35 (80%) cases; 9q copy neutral loss of heterozygosity targeting the PTCH1 locus was identified in 15 (34%) cases. No genomic aberrations were identified in other sequenced SHH pathway members. In summary, we demonstrate PTCH1 inactivating mutations in 93% of sporadic KCOTs, indicating that SHH pathway alterations are a near-universal event in these benign but locally aggressive neoplasms. The high frequency of complete PTCH1 loss of function may provide a rational target for SHH pathway inhibitors to be explored in future studies.

Genodermatoses with malignant potential

The hereditary nature of some forms of cancer was recognized long ago. Over time, recognition of associated findings led to the delineation of numerous hereditary cancer syndromes. Many of these syndromes also have cutaneous manifestations, the recognition of which can lead to their early identification. Recognition of these syndromes allows vigilant surveillance and preemptive treatment, which can dramatically impact the risks of morbidity and mortality for affected patients. The rise of rapid and accurate genetic testing now allows the early identification of asymptomatic at risk family members so that monitoring can be initiated as early as possible. The dermatologist plays a critical role in early identification of these syndromes and, in many cases, their treatment. This review summarizes many known hereditary cancer syndromes with cutaneous findings, their etiology, identification, evaluation, and management. Importantly, this is an ever evolving topic and new findings and syndromes will continue to be recognized. The dermatologist must be always alert to ensure they are detected.

Unexpected phenotype in a frameshift mutation of PTCH1

BACKGROUND

Gorlin syndrome, also known as basal cell nevus syndrome (BCNS), is a rare autosomal dominant genetic condition, characterized by the presence of multiple basal cell carcinomas at a young age, odontogenic keratocysts, skeletal anomalies, macrocephaly, and dysmorphisms. BCNS is mainly caused by mutations in PTCH1, an onco-suppressor gene that maps at 9q22.3 region. A disease related to BCNS is the 9q22.3 microdeletion syndrome. This condition has an overlapping clinical phenotype with the BCNS, but it can present in addition: metopic craniosynostosis, overgrowth, obstructive hydrocephalus, developmental delay, intellectual disability, and seizures. This syndrome is caused by the deletion of a genomic region containing the PTCH1 and the FANCC.

METHODS AND RESULTS

We report the case of an 11-year-old girl that came to our attention for overgrowth, dysmorphic features of the face, and craniosynostosis, but with a normal intellectual and motor development. At first we performed an array-comparative genomic hybridization (aCGH) analysis. The analysis showed no copy number changes. Then, we performed the analysis of the PTCH1 by next-generation sequencing. This analysis showed a heterozygous frameshift mutation.

CONCLUSION

This is the first case with a PTCH1 point mutation with a 9q22.3 microdeletion syndrome phenotype. This finding may strengthen the importance of the role of the PTCH1, especially regarding the metopic craniosynostosis.

Ocular manifestations in Gorlin-Goltz syndrome

Background

Gorlin-Goltz syndrome, also known as nevoid basal cell carcinoma syndrome, is a rare genetic disorder that is transmitted in an autosomal dominant manner with complete penetrance and variable expressivity. It is caused in 85% of the cases with a known etiology by pathogenic variants in the PTCH1 gene, and is characterized by a wide range of developmental abnormalities and a predisposition to multiple neoplasms. The manifestations are multiple and systemic and consist of basal cell carcinomas in various regions, odontogenic keratocistic tumors and skeletal anomalies, to name the most frequent. Despite the scarce medical literature on the topic, ocular involvement in this syndrome is frequent and at the level of various ocular structures. Our study focuses on the visual apparatus and its annexes in subjects with this syndrome, in order to better understand how this syndrome affects the ocular system, and to evaluate with greater accuracy and precision the nature of these manifestations in this group of patients.

Results

Our study confirms the presence of the commonly cited ocular findings in the general literature regarding the syndrome [hypertelorism (45.5%), congenital cataract (18%), nystagmus (9%), colobomas (9%)] and highlights strabismus (63% of the patients), epiretinal membranes (36%) and myelinated optic nerve fiber layers (36%) as the most frequent ophthalmological findings in this group of patients.

Conclusions

The presence of characteristic and frequent ocular signs in the Gorlin- Goltz syndrome could help with the diagnostic process in subjects suspected of having the syndrome who do not yet have a diagnosis. The ophthalmologist has a role as part of a multidisciplinary team in managing these patients. The ophthalmological follow-up that these patients require, can allow, if necessary, a timely therapy that could improve the visual prognosis of such patients.

Familial Syndromes Involving Meningiomas Provide Mechanistic Insight Into Sporadic Disease

Currently, there is an incomplete understanding of the molecular pathogenesis of meningiomas, the most common primary brain tumor. Several familial syndromes are characterized by increased meningioma risk, and the genetics of these syndromes provides mechanistic insight into sporadic disease. The best defined of these syndromes is neurofibromatosis type 2, which is caused by a mutation in the NF2 gene and has a meningioma incidence of approximately 50%. This finding led to the subsequent discovery that NF2 loss-of-function occurs in up to 60% of sporadic tumors. Other important familial diseases with increased meningioma risk include nevoid basal cell carcinoma syndrome, multiple endocrine neoplasia 1 (MEN1), Cowden syndrome, Werner syndrome, BAP1 tumor predisposition syndrome, Rubinstein-Taybi syndrome, and familial meningiomatosis caused by germline mutations in the SMARCB1 and SMARCE1 genes. For each of these syndromes, the diagnostic criteria, incidence in the population, and frequency of meningioma are presented to review the relevant clinical information for these conditions. The genetic mutations, molecular pathway derangements, and relationship to sporadic disease for each syndrome are described in detail to identify targets for further investigation. Familial syndromes characterized by meningiomas often affect genes and pathways that are also implicated in a subset of sporadic cases, suggesting key molecular targets for therapeutic intervention. Further studies are needed to resolve the functional relevance of specific genes whose significance in sporadic disease remains to be elucidated.

Hedgehog pathway inhibition as a therapeutic target in acute myeloid leukemia

Introduction: The Hedgehog (HH) pathway constitutes a collection of signaling molecules which critically influence embryogenesis. In adults, however, the HH pathway remains integral to the proliferation, maintenance, and apoptosis of adult stem cells including hematopoietic stem cells. Areas covered: We discuss the current understanding of the HH pathway as it relates to normal hematopoiesis, the pathology of acute myeloid leukemia (AML), the rationale for and data from combination therapies including HH pathway inhibitors, and ultimately the prospects that might offer promise in targeting this pathway in AML. Expert opinion: Efforts to target the HH pathway have been focused on impeding this disposition and restoring chemosensitivity to conventional myeloid neoplasm therapies. The year 2018 saw the first approval of a HH pathway inhibitor (glasdegib) for AML, though for an older population and in combination with an uncommonly-used therapy. Several other clinical trials with agents targeting modulators of HH signaling in AML and MDS are underway. Further study and understanding of the interplay between the numerous aspects of HH signaling and how it relates to the augmented survival of AML will provide a more reliable substrate for therapeutic strategies in patients with this poor-risk disease.

Novel SUFU Frameshift Variant Leading to Meningioma in Three Generations in a Family with Gorlin Syndrome

Gorlin syndrome is mainly caused by pathogenic germline variants in the tumour suppressor genes PTCH1 and SUFU, both regulatory genes in the hedgehog pathway. However, the phenotypes of patients with PTCH1 and SUFU pathogenic variants seem to differ. We present a family with a frameshift variant in the SUFU gene c.954del, p.Asn319Thrfs∗42 leading to meningiomas and multiple basal cell-carcinomas.

MicroRNAs profiling in fibroblasts derived from patients with Gorlin syndrome

Gorlin syndrome (GS) is a hereditary disorder with tumorigenicity, caused by constitutive hyperactivity of hedgehog signaling. Smoothened (SMO) antagonists have been effectively used in the clinical treatment of hedgehog signaling-related cancer. However, these treatments have led to problematic side effects, including severe adverse reactions and drug resistance from additional somatic mutations. We profiled microRNAs in GS fibroblasts to explore a novel therapeutic target for controlling hyper-activated hedgehog signaling. To identify GS-related microRNAs, we analyzed dermal fibroblasts from five patients with GS and three normal controls. We used microarray comparative genomic hybridization to screen 632 human microRNAs in GS fibroblasts. We identified 16 down- and 19 upregulated microRNAs with over twofold change in expression. We validated the increased expression of four microRNAs, confirming hsa-miR-196a-5p downregulation and hsa-miR-4485 upregulation using real-time PCR. Moreover, hsa-miR-196a-5p is complementary to sites in the 3' UTR of MAP3K1, which exhibits upregulated expression at mRNA and protein levels in GS fibroblasts. In addition, hedgehog signal induction with exogenous components decreased miR-196a-5p expression and increased map3k1 expression in a mouse mesenchymal cell line. Given that MAP3K1 has been reported to activate hedgehog signaling, hsa-miR-196a-5p may contribute to the positive feedback loop in this pathway.

Mutations in SUFU and PTCH1 genes may cause different cutaneous cancer predisposition syndromes: similar, but not the same

Many cancer predisposition syndromes are preceded or accompanied by a range of typical skin signs. Gorlin syndrome is a rare multisystem inherited disorder which can predispose to basal cell carcinomas (BCCs), childhood medulloblastomas in addition to various developmental abnormalities; the majority of cases are due to mutations in the PTCH1 gene. Approximately 5% of cases have been attributed to a mutation in the SUFU gene. Certain phenotypic features have been identified as being more prevalent in individuals with a SUFU mutation such as childhood medulloblastoma, infundibulocystic BCCs and trichoepitheliomas. Recently hamartomatous skin lesions have also been noted in families with childhood medulloblastoma, a "Gorlin like" phenotype and a SUFU mutation. Here we describe a family previously diagnosed with Gorlin syndrome with a novel SUFU splice site deleterious genetic variant, who have several dermatological features including palmar sclerotic fibromas which has not been described in relation to a SUFU mutation before. We highlight the features more prominent in individuals with a SUFU mutation. It is important to note that emerging therapies for treatment of BCCs in patients with a PTCH1 mutation may not be effective in those with a SUFU mutation.

Whole-exome sequencing of nevoid basal cell carcinoma syndrome families and review of Human Gene Mutation Database PTCH1 mutation data

Background

Nevoid basal cell carcinoma syndrome (NBCCS) is an autosomal dominant disorder with variable expression and nearly complete penetrance. PTCH1 is the major susceptibility locus and has no known hot spots or genotype–phenotype relationships.

Methods

We evaluated 18 NBCCS National Cancer Institute (NCI) families plus PTCH1 data on 333 NBCCS disease‐causing mutations (DM) reported in the Human Gene Mutation Database (HGMD). National Cancer Institute families underwent comprehensive genomic evaluation, and clinical data were extracted from NCI and HGMD cases. Genotype–phenotype relationships were analyzed using Fisher's exact tests focusing on mutation type and PTCH1 domains.

Results

PTCH1 pathogenic mutations were identified in 16 of 18 NCI families, including three previously mutation‐negative families. PTCH1 mutations were spread across the gene with no hot spot. After adjustment for multiple tests, a statistically significant genotype–phenotype association was observed for developmental delay and gross deletion–insertions (p = 9.0 × 10⁻⁶), and suggestive associations between falx cerebri calcification and all transmembrane domains (p = 0.002) and severe outcomes and gross deletion–insertions (p = 4.0 × 10⁻⁴).

Conclusion

Overall, 89% of our NCI families had a pathogenic PTCH1 mutation. The identification of PTCH1 mutations in previously mutation‐negative families underscores the importance of repeated testing when new technologies become available. Additional clinical information linked to mutation databases would enhance follow‐up and future studies of genotype–phenotype relationships.

Cardiac Fibroma with Ventricular Tachycardia: An Unusual Clinical Presentation of Nevoid Basal Cell Carcinoma Syndrome

Pediatric cardiac tumors are rare and often benign with an incidence of approximately 0.03-0.32% and can be associated with genetic conditions. For example, approximately 3% of individuals with nevoid basal cell carcinoma syndrome (NBCCS), also known as Gorlin syndrome, have a cardiac fibroma. NBCCS is also characterized by lamellar or early calcification of the falx, jaw keratocysts, palmar and/or plantar pits, and a predisposition for basal cell carcinomas. Given the management implications of NBCCS, including appropriate cancer screenings and precautions, prompt identification of affected individuals is critical. We report a case of a 6-year-old female presenting with ventricular tachycardia secondary to cardiac fibroma. After diagnosis of recurrent jaw keratocysts, she was clinically and molecularly diagnosed with NBCCS. Identification of a cardiac fibroma should prompt careful assessment of past medical and family history with consideration of a diagnosis of NBCCS.

A Novel PTCH1 Frameshift Mutation Leading to Nevoid Basal Cell Carcinoma Syndrome

Nevoid basal cell carcinoma syndrome (NBCCS), also known as Gorlin syndrome, is a rare multisystemic autosomal dominant disorder typically presenting with cutaneous basal cell carcinomas, multiple keratocysts, and skeletal anomalies. NBCCS is caused by heterozygous mutations in the PTCH1 gene in chromosome 9q22, in the PTCH2 gene in 1p34, or the SUFU gene in 10q24.32. Here, we report on an 18-month-old boy presenting with medulloblastoma, frontal bossing, and multiple skeletal anomalies and his father who has basal cell carcinomas, palmar pits, macrocephaly, bifid ribs, calcification of falx cerebri, and a history of surgery for odontogenic keratocyst. These clinical findings were compatible with the diagnosis of NBCCS, and a novel mutation, c.1249delC; p.Gln417Lysfs*15, was found in PTCH1 causing a premature stop codon.