Podcast
Questions and Answers
What is the most commonly observed clinical feature in patients with dyskeratosis congenita?
What is the most commonly observed clinical feature in patients with dyskeratosis congenita?
Which age group typically exhibits signs of nail dystrophy in dyskeratosis congenita?
Which age group typically exhibits signs of nail dystrophy in dyskeratosis congenita?
What inheritance pattern is most commonly associated with dyskeratosis congenita?
What inheritance pattern is most commonly associated with dyskeratosis congenita?
Which of the following is NOT a typical mucocutaneous finding in dyskeratosis congenita?
Which of the following is NOT a typical mucocutaneous finding in dyskeratosis congenita?
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Which of these cancers is associated with an increased risk in patients with dyskeratosis congenita?
Which of these cancers is associated with an increased risk in patients with dyskeratosis congenita?
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Which gene is most commonly implicated in telomere maintenance associated with dyskeratosis congenita?
Which gene is most commonly implicated in telomere maintenance associated with dyskeratosis congenita?
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What is the typical prevalence rate of dyskeratosis congenita?
What is the typical prevalence rate of dyskeratosis congenita?
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Which of the following symptoms is caused by bone marrow failure in dyskeratosis congenita?
Which of the following symptoms is caused by bone marrow failure in dyskeratosis congenita?
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What is the primary consequence of telomere shortening due to the lack of dyskerin?
What is the primary consequence of telomere shortening due to the lack of dyskerin?
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Which gene is most commonly associated with telomere elongation?
Which gene is most commonly associated with telomere elongation?
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Which protein complex is coded by TINF2 and ACD for telomere protection?
Which protein complex is coded by TINF2 and ACD for telomere protection?
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What essential criterion must be demonstrated to confirm a clinical diagnosis related to telomere shortening?
What essential criterion must be demonstrated to confirm a clinical diagnosis related to telomere shortening?
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Which gene is involved in the control of mRNA stability at the telomeres?
Which gene is involved in the control of mRNA stability at the telomeres?
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What percentage of patients may experience bone marrow failure by the age of 40 years?
What percentage of patients may experience bone marrow failure by the age of 40 years?
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Which component is primarily involved in recruiting telomerase to the telomere?
Which component is primarily involved in recruiting telomerase to the telomere?
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Which of the following describes a cutaneous finding associated with telomere-related conditions?
Which of the following describes a cutaneous finding associated with telomere-related conditions?
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What is the primary genetic cause of Bloom syndrome?
What is the primary genetic cause of Bloom syndrome?
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Which of the following clinical features is most commonly associated with Bloom syndrome?
Which of the following clinical features is most commonly associated with Bloom syndrome?
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What type of cancer are individuals with Bloom syndrome at the greatest risk of developing?
What type of cancer are individuals with Bloom syndrome at the greatest risk of developing?
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Which immunological condition is most likely to be present in individuals with Bloom syndrome?
Which immunological condition is most likely to be present in individuals with Bloom syndrome?
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How significantly are individuals with Bloom syndrome at risk of developing cancers compared to the general population?
How significantly are individuals with Bloom syndrome at risk of developing cancers compared to the general population?
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Which characteristic feature is least likely to be associated with Bloom syndrome?
Which characteristic feature is least likely to be associated with Bloom syndrome?
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Which epidemiological fact is true about Bloom syndrome?
Which epidemiological fact is true about Bloom syndrome?
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What is a common reproductive issue faced by men with Bloom syndrome?
What is a common reproductive issue faced by men with Bloom syndrome?
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What is the primary result of loss of BLM function in Bloom syndrome?
What is the primary result of loss of BLM function in Bloom syndrome?
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Which population has the highest estimated prevalence of Bloom syndrome?
Which population has the highest estimated prevalence of Bloom syndrome?
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What is an essential diagnostic criterion for confirming a diagnosis of Bloom syndrome?
What is an essential diagnostic criterion for confirming a diagnosis of Bloom syndrome?
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What is the main cause of death in individuals with Bloom syndrome?
What is the main cause of death in individuals with Bloom syndrome?
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What is the recommended measure to minimize health risks for children with Bloom syndrome?
What is the recommended measure to minimize health risks for children with Bloom syndrome?
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Which feature is NOT typically observed in Bloom syndrome?
Which feature is NOT typically observed in Bloom syndrome?
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What location on the chromosome is the BLM gene found?
What location on the chromosome is the BLM gene found?
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Which of the following is a method for diagnosing Bloom syndrome?
Which of the following is a method for diagnosing Bloom syndrome?
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What role does ATM protein primarily play in the cell?
What role does ATM protein primarily play in the cell?
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Which of the following is NOT a characteristic feature of ataxia telangiectasia (AT)?
Which of the following is NOT a characteristic feature of ataxia telangiectasia (AT)?
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What percentage of head and neck squamous cell carcinoma (HNSCC) cases have been associated with hypermethylation of the ATM promoter?
What percentage of head and neck squamous cell carcinoma (HNSCC) cases have been associated with hypermethylation of the ATM promoter?
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Which protein complex is important for the optimal activation of ATM at DNA double-stranded breaks?
Which protein complex is important for the optimal activation of ATM at DNA double-stranded breaks?
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Which statement accurately describes the pathogenesis of ATM mutations?
Which statement accurately describes the pathogenesis of ATM mutations?
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What is the estimated lifetime risk of malignancy in patients with ataxia telangiectasia?
What is the estimated lifetime risk of malignancy in patients with ataxia telangiectasia?
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Which of the following is considered an essential diagnostic criterion for ataxia telangiectasia?
Which of the following is considered an essential diagnostic criterion for ataxia telangiectasia?
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What additional roles does ATM protein serve in cellular functions aside from DNA repair?
What additional roles does ATM protein serve in cellular functions aside from DNA repair?
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What is the inheritance pattern of Ataxia–telangiectasia?
What is the inheritance pattern of Ataxia–telangiectasia?
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Which symptoms are commonly associated with Ataxia–telangiectasia?
Which symptoms are commonly associated with Ataxia–telangiectasia?
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Where is the ATM gene located in the human genome?
Where is the ATM gene located in the human genome?
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Which of the following tumors is least likely to develop in patients with Ataxia–telangiectasia?
Which of the following tumors is least likely to develop in patients with Ataxia–telangiectasia?
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What is the typical incidence rate of Ataxia–telangiectasia?
What is the typical incidence rate of Ataxia–telangiectasia?
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Which feature is often absent in patients with variant Ataxia–telangiectasia?
Which feature is often absent in patients with variant Ataxia–telangiectasia?
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What type of immune deficiency is commonly seen in individuals with Ataxia–telangiectasia?
What type of immune deficiency is commonly seen in individuals with Ataxia–telangiectasia?
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Which anatomical region commonly experiences lymphoid neoplasms in patients with Ataxia–telangiectasia?
Which anatomical region commonly experiences lymphoid neoplasms in patients with Ataxia–telangiectasia?
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Which imaging method is used for cluster 2 tumours?
Which imaging method is used for cluster 2 tumours?
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What genetic alteration is primarily linked to familial paragangliomas?
What genetic alteration is primarily linked to familial paragangliomas?
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What morphological feature can suggest a genetic predisposition in paragangliomas?
What morphological feature can suggest a genetic predisposition in paragangliomas?
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Which immunohistochemical marker is commonly identified in paraganglioma cells?
Which immunohistochemical marker is commonly identified in paraganglioma cells?
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What is typically characterized by a loss of expression of fumarate hydratase in familial paragangliomas?
What is typically characterized by a loss of expression of fumarate hydratase in familial paragangliomas?
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What is a criterion that has a high predictive value for identifying SDHB, SDHC, or SDHD mutations?
What is a criterion that has a high predictive value for identifying SDHB, SDHC, or SDHD mutations?
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What is the estimated five-year overall survival rate for patients with metastatic paraganglioma?
What is the estimated five-year overall survival rate for patients with metastatic paraganglioma?
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Which main characteristic feature differentiates SDH-associated paragangliomas from sporadic ones?
Which main characteristic feature differentiates SDH-associated paragangliomas from sporadic ones?
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What is a desirable diagnostic criterion for familial paragangliomas?
What is a desirable diagnostic criterion for familial paragangliomas?
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What is a characteristic localization for sympathetic-derived paragangliomas?
What is a characteristic localization for sympathetic-derived paragangliomas?
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Which clinical feature is primarily associated with catecholamine excess from sympathetic paragangliomas?
Which clinical feature is primarily associated with catecholamine excess from sympathetic paragangliomas?
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Which cluster of tumours tends to be clinically silent and is often non-secretory?
Which cluster of tumours tends to be clinically silent and is often non-secretory?
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What type of imaging is useful for visualizing cluster 1 tumours due to SSTR expression?
What type of imaging is useful for visualizing cluster 1 tumours due to SSTR expression?
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Which of the following best describes the secretion profile of parasympathetic paragangliomas?
Which of the following best describes the secretion profile of parasympathetic paragangliomas?
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What is the consequence of the catecholamine profile in familial paragangliomas?
What is the consequence of the catecholamine profile in familial paragangliomas?
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Which region are parasympathetic-derived paragangliomas most likely to arise from?
Which region are parasympathetic-derived paragangliomas most likely to arise from?
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What type of paraganglioma typically leads to the symptoms of sweating and anxiety?
What type of paraganglioma typically leads to the symptoms of sweating and anxiety?
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What is a clinical characteristic of spiradenomas and cylindromas in Brooke–Spiegler syndrome?
What is a clinical characteristic of spiradenomas and cylindromas in Brooke–Spiegler syndrome?
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In Brooke–Spiegler syndrome, where are salivary gland tumors primarily located?
In Brooke–Spiegler syndrome, where are salivary gland tumors primarily located?
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Which of the following terms is NOT considered acceptable terminology related to Brooke–Spiegler syndrome?
Which of the following terms is NOT considered acceptable terminology related to Brooke–Spiegler syndrome?
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What is the primary genetic inheritance pattern of Brooke–Spiegler syndrome?
What is the primary genetic inheritance pattern of Brooke–Spiegler syndrome?
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What defines the phenotypic variant of Brooke–Spiegler syndrome known as multiple familial trichoepithelioma?
What defines the phenotypic variant of Brooke–Spiegler syndrome known as multiple familial trichoepithelioma?
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How does the number of cutaneous tumors associated with Brooke–Spiegler syndrome typically change over time?
How does the number of cutaneous tumors associated with Brooke–Spiegler syndrome typically change over time?
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What is the usual size range for nodules formed by spiradenomas, cylindromas, and spiradenocylindromas?
What is the usual size range for nodules formed by spiradenomas, cylindromas, and spiradenocylindromas?
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Which feature is a potential indicator of malignant transformation in Brooke–Spiegler syndrome tumors?
Which feature is a potential indicator of malignant transformation in Brooke–Spiegler syndrome tumors?
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What is the common feature of benign cutaneous and salivary gland tumors observed macroscopically?
What is the common feature of benign cutaneous and salivary gland tumors observed macroscopically?
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Which type of mutation is most commonly reported in the CYLD gene?
Which type of mutation is most commonly reported in the CYLD gene?
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In which age group is salivary gland involvement typically observed in at-risk patients?
In which age group is salivary gland involvement typically observed in at-risk patients?
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What histopathological feature differentiates membranous-type basal cell adenomas (BCAs) from pleomorphic adenomas?
What histopathological feature differentiates membranous-type basal cell adenomas (BCAs) from pleomorphic adenomas?
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Which of the following statements is true regarding the facial nerve and parotid neoplasms?
Which of the following statements is true regarding the facial nerve and parotid neoplasms?
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What type of inheritance is observed for the pathogenic variant in the CYLD gene associated with BSS?
What type of inheritance is observed for the pathogenic variant in the CYLD gene associated with BSS?
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Which characteristic appearance is associated with cylindroma on histopathology?
Which characteristic appearance is associated with cylindroma on histopathology?
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What is true regarding the clone of tumor cells in membranous-type BCA?
What is true regarding the clone of tumor cells in membranous-type BCA?
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Which combination of tumors indicates a higher suspicion for BSS?
Which combination of tumors indicates a higher suspicion for BSS?
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Which factor is NOT a consideration in the inheritance pattern of the CYLD gene mutations?
Which factor is NOT a consideration in the inheritance pattern of the CYLD gene mutations?
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Which of the following is a significant consideration for the prognosis of salivary gland membranous-type BCA?
Which of the following is a significant consideration for the prognosis of salivary gland membranous-type BCA?
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What type of tumorous growth pattern is primarily associated with cylindrical neoplasms?
What type of tumorous growth pattern is primarily associated with cylindrical neoplasms?
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What symptom is prevalent in patients with multiple familial trichoepitheliomas (MFT)?
What symptom is prevalent in patients with multiple familial trichoepitheliomas (MFT)?
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Which immunohistochemical markers are present in the cell nests of membranous-type BCAs?
Which immunohistochemical markers are present in the cell nests of membranous-type BCAs?
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Study Notes
Clinical Features
- Characterized by a triad: oral leukoplakia (80%), nail dystrophy (90%), and reticulate hyperpigmentation/poikiloderma (80-90%).
- Oral leukoplakia most often appears on the tongue.
- Nail dystrophy presents as longitudinal ridging, typically observed between ages 5-13.
- Reticular hyperpigmentation shows a fine, lace-like pattern, commonly on the face, upper trunk, and upper arms.
- Additional mucocutaneous findings include adermatoglyphia (absence of fingerprints), palmoplantar hyperkeratosis, early greying, hair loss (scalp or eyelashes), and epiphora (watering eyes).
- Bone marrow failure occurs in 90% of cases by the second decade of life.
- Increased risk of squamous cell carcinoma of head and neck, upper aerodigestive tract cancers (esophageal carcinoma, gastric adenocarcinoma), and hematological malignancies like myelodysplasia and Hodgkin lymphoma.
Epidemiology
- Prevalence is approximately 1 in 1 million.
Etiology
- Caused by pathogenic sequence variants in genes involved in telomere biology.
- Most common inheritance pattern is X-linked recessive (DKC1).
- Other inheritance patterns include autosomal dominant (TERC, TINF2), autosomal recessive (NOP10, NHP2, WRAP53, CTC1), and both autosomal dominant or recessive (TERT).
- De novo mutations can occur with TINF2.
Pathogenesis
- Telomeres, non-coding sequences at chromosome ends, are maintained by telomerase, which prevents telomere shortening during cell division.
- Primary gene affected is DKC1, encoding dyskerin essential for telomere maintenance.
- Without dyskerin, telomeres shorten, leading to cellular apoptosis, senescence, and DNA replication issues.
- Telomere-related genes include DKC1, TERC, TERT, NOP10, NHP2 (telomerase complex), TINF2, ACD (shelterin complex), and CTC1 (CST complex).
Histopathology
- Nonspecific cutaneous findings: epidermal atrophy, dermal telangiectasia, and pigment incontinence.
Diagnostic Molecular Pathology
- Diagnosis confirmed by telomere length testing, showing lengths below the first percentile in peripheral blood leukocytes.
- Gene sequencing can help confirm diagnosis.
Essential and Desirable Diagnostic Criteria
- Essential criteria: telomere shortening in peripheral blood; clinical findings in skin, nails, or mouth.
- Desirable criteria: mutations in affected genes, including DKC1, TERC, TERT, among others.
Prognosis and Prediction
- Prognosis depends on genetic and environmental factors.
- Mild cases may have few clinical features; severe cases may lead to bone marrow failure by age 20.
- By age 40, 40% of patients may experience bone marrow failure.
Bloom Syndrome Overview
- Rare autosomal recessive chromosomal breakage syndrome caused by mutations in the BLM gene.
- Characterized by a significantly increased risk of tumors, including oropharyngeal carcinoma.
Genetic Information
- MIM Number: 210900
- ICD-O Coding: Specific coding not defined.
- ICD-11 Coding: 4A01.31, classified under DNA repair defects other than combined T-cell or B-cell immunodeficiencies.
Clinical Features
- Prominent physical characteristics include small stature, reduced weight, and head size, along with a lack of subcutaneous fat.
- Skin rash commonly appears on the cheeks and nose after sun exposure during infancy.
- Distinctive facial features: long and narrow face, prominent nose and ears, and small lower jaw.
- Affected individuals generally maintain normal intellectual abilities.
- Fertility issues: men often face infertility (azoospermia and oligospermia), while women may be fertile but commonly experience early menopause.
- Immune system abnormalities lead to recurrent infections in infants and increase risks of chronic obstructive lung disease and type 2 diabetes.
- Cancer risk is significantly elevated (150–300 times higher than normal), with 66% of cases involving solid tumors and 33% leukemia/lymphoma.
Cancer Incidence
- Colorectal cancer is the most prevalent tumor (29 cases), followed by skin, breast, and oropharyngeal cancers (24 cases each).
Epidemiology
- First described in 1954 by David Bloom in New York City.
- Approximately 283 cases reported in the Bloom Syndrome Registry.
- Estimated prevalence in the Ashkenazi Jewish population is 1 in 48,000 births.
- A specific founder mutation (BLM(Ash)) is prevalent among 1 in 100 individuals of Ashkenazi Jewish descent, with additional mutations observed in Slavic and Hispanic populations.
Etiology
- Caused by mutations in the BLM gene located on chromosome 15q26.1, encoding a member of the RECQ family of DNA helicases.
Pathogenesis
- Loss of BLM function leads to errors during DNA replication, resulting in chromosomal rearrangements and increased genetic instability, contributing to cancer predisposition.
Diagnosis
- Confirmatory tests may include detecting biallelic pathogenic variants in the BLM gene and increased frequency of sister-chromatid exchanges in cytogenetic studies.
- Essential diagnostic criteria: presence of clinical features such as small size and distinctive facial traits, along with identification of BLM mutation.
Prognosis
- Main cause of mortality is cancer and related complications, typically occurring in the third decade of life.
- Prevention strategies include avoidance of sun exposure to the face and limiting ionizing radiation, alongside regular cancer screening and surveillance.
Ataxia–telangiectasia (AT)
- Autosomal recessive disorder caused by pathogenic variants in the ATM gene.
- Different diseases can affect multiple systems due to the condition.
Coding and Identification
- ICD-O code: MIM 208900 for Ataxia–telangiectasia (AT).
- ICD-11 code: 4A01.31 denotes DNA repair defects not linked to combined T-cell or B-cell immunodeficiencies.
Terminology and Subtypes
- Louis–Bar syndrome is not recommended terminology for AT.
- Variant ataxia–telangiectasia exists, characterized by milder symptoms.
Clinical Manifestations
- Symptoms include progressive cerebellar ataxia, cerebellar degeneration, and telangiectases in sun-exposed areas.
- Other symptoms: recurrent sinopulmonary infections, hypogonadism, insulin resistance, and malignancies.
- Malignancies often present as lymphoid neoplasms of B- and T-cell lineages with distinctions in head and neck involvement.
Epidemiology
- Incidence: Approximately 1 case per 40,000–100,000 births, with global prevalence.
Etiology
- Caused by homozygous pathogenic sequence variants in the ATM gene at chromosome region 11q22.3.
- Some cases involve mutations in MRE11 resulting in a variant AT-like disorder.
Pathogenesis
- ATM gene has 66 exons, mutations are scattered with no distinct hotspots.
- Most pathogenic variants lead to classic phenotypes, while some missense mutations cause milder forms (variant AT).
- ATM is a protein kinase involved in DNA repair, especially double-stranded breaks, and related to other cellular functions including cell cycle regulation and apoptosis.
Tumor Characteristics
- No observable differences between AT-associated tumors and sporadic tumor presentations in macroscopic, histopathological, and cytological analyses.
Diagnostic Molecular Pathology
- ATM-related deletions noted in head and neck squamous cell carcinoma (HNSCC).
- Hypermethylation of the ATM promoter found in 25% of HNSCCs, correlating with decreased ATM expression.
Diagnostic Criteria
- Essential criteria include characteristic neurological symptoms, telangiectases, elevated serum AFP levels in over 95% of patients, decreased immunoglobulins, lymphopenia, increased chromosome breakage post-X-ray exposure, and the presence of ATM pathogenic variants.
Prognosis
- Patients with AT have a lifetime cancer risk of 25%.
- Leading causes of death are cancer and respiratory insufficiency.
Familial Paraganglioma Syndromes
- Inherited cancer syndromes characterized by the presence of paragangliomas.
- ICD-O coding: MIM #27513; ICD-11 coding: None available.
- Related terminology includes familial paraganglioma-phaeochromocytoma syndromes and hereditary paraganglioma-phaeochromocytoma syndromes.
Localization and Types
- Parasympathetic-derived paragangliomas commonly found in the head and neck, especially at the carotid body and along glossopharyngeal and vagus nerves.
- Sympathetic-derived paragangliomas typically are intra-adrenal (phaeochromocytoma) or retroperitoneal.
Clinical Features
- Symptoms often result from catecholamine excess, including sweating, palpitations, anxiety, hypertension, and tachycardia.
- Parasympathetic paragangliomas may secrete dopamine but often present with minimal clinical manifestations.
- Genotype-phenotype correlation observed in catecholamine profiles.
Tumor Classifications
- Cluster 1 Tumors: Pseudohypoxic pathogenesis, usually non-secretory or dopamine-secreting, express somatostatin receptors (SSTR) and are best visualized by 68Ga-DOTATATE PET-CT.
- Cluster 2 Tumors: Exhibit kinase signaling, potentially functional, can be imaged with FDOPA PET-CT or 123I-MIBG.
Epidemiology
- Approximately 40% of paragangliomas are hereditary.
- Constitutional pathogenic sequence variants connected to younger age at presentation and presence of multiple or extra-adrenal tumors.
Etiology and Pathogenesis
- Genetic alterations are the main cause of familial paraganglioma syndromes.
- Tumors may present as multifocal and can resemble conditions seen in multiple endocrine neoplasia type 2.
Histopathology
- Familial paragangliomas have overlapping morphology with sporadic forms, with potential genetic predisposition features.
- SDH-associated tumors may show distinct patterns, while von Hippel–Lindau syndrome-associated tumors often present clear cells with vacuolation.
Immunohistochemistry
- Tumors express neuroendocrine markers and various indicators can assist in diagnosing familial disease.
- Loss of SDHB immunoreactivity indicates the presence of SDH-related diseases, with specific markers identifying mutations.
Cytological Diagnosis
- Diagnosis can be challenging but enhanced by immunohistochemistry.
Genetic Testing and Diagnostic Criteria
- Genetic testing is essential to confirm responsible mutations.
- Essential diagnostic criteria: at least one paraganglioma or confirmed pathogenic sequence variant in a susceptibility gene.
- Desirable criteria include loss of SDHB immunoreactivity indicating potential mutations.
Staging
- TNM staging applicable for phaeochromocytomas and sympathetic paragangliomas; no published system for extra-adrenal paragangliomas in the head and neck.
Prognosis and Survival
- Most paragangliomas are amenable to surgical resection.
- Challenges include large tumors and multifocality, mimicking metastasis.
- Five-year overall survival rates for metastatic paraganglioma range from 50% to 70%.
Overview of Brooke–Spiegler Syndrome (BSS)
- Inherited autosomal dominant disorder.
- Characterized by multiple skin tumors: spiradenomas, cylindromas, spiradenocylindromas, and trichoepitheliomas.
- Associated with salivary gland tumors, particularly basal cell adenoma (BCA), membranous type.
Genetic and Coding Information
- ICD-O coding: relevant for neoplasm classification.
- MIM number for BSS: 605041.
- Other related conditions include cylindromatosis (132700) and multiple familial trichoepithelioma (601606).
Localization of Tumors
- Skin tumors primarily located on head and neck.
- Trichoepitheliomas commonly found in nasolabial folds.
- Salivary gland tumors typically occur in the parotid gland; rarely affect submandibular glands.
Clinical Features
- Tumors present as multiple nodules (5–30 mm), often skin-colored, reddish, or blue.
- Trichoepitheliomas are small (2–10 mm), bilateral, and frequently confluent.
- Tumor growth continues throughout life and increases with age.
- Signs of malignancy include rapid growth, ulceration, and bleeding, particularly in older patients.
Epidemiology
- BSS and related conditions are rare; precise incidence rates are unknown.
- 1-2% of BSS patients develop salivary gland tumors; MFT typically presents only with skin lesions.
- Skin tumors generally emerge around puberty; salivary gland involvement often seen post-40 years.
Etiology and Pathogenesis
- Caused by heterozygous pathogenic variants in the CYLD gene linked to tumor suppression.
- Mutations predominantly in exons 9–20; over 100 variations reported.
- Somatic mutations observed in cutaneous neoplasms.
Macroscopic and Histopathological Features
- Tumors appear as unencapsulated, ovoid to round nodules.
- Membranous-type BCA displays homogeneous tan cut surfaces and multicentric growth.
- Histologically, classic features include peripheral palisading of dark cells and a dense hyaline stroma.
Diagnostic Criteria
- Essential for diagnosis: presence of multiple inherited and histologically confirmed skin tumors or identification of pathogenic variants in the CYLD gene.
- Salivary gland tumors can raise suspicion for BSS if they accompany skin lesions.
Prognosis and Malignancy Potential
- Salivary gland membranous-type BCA and skin lesions (spiradenoma, cylindroma) are generally benign.
- Development of malignant tumors can occur, usually presenting aggressive growth or metastasis.
- Prognostic data remains sparse due to rarity and variability of lesions.
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Description
Test your knowledge on the clinical features of a disease characterized by hyperpigmentation, nail dystrophy, and oral leukoplakia. This quiz focuses on the signs and prevalence of these conditions, particularly in specific age groups. Assess your understanding of this triad and its implications.