An overlap of Cowden's disease and Bannayan-Riley-Ruvalcaba syndrome in the same family

Bannayan-Riley-Ruvalcaba syndrome with deforming lipomatous hamartomas in infant--case report

Bannayan-Riley-Ruvalcaba Syndrome is a rare condition caused by mutations in the PTEN gene. It displays association of multiple lipomas, macrocephaly, hemangiomas, hamartomatous intestinal polyposis, developmental delay and speckled pigmented maculae on the male genitalia. We report the case of a nine-month-old boy who had fast growing and progressive tumors for three months, macrocephaly and lentigines on the penis. Imaging tests showed extensive lipomatosis with invasion of paraspinal muscles, enlargement of the spinal canal and spinal cord compression; after surgical excision of the mass, the pathology was consistent with lipoma. Adipocyte culture karyotype demonstrated PTEN mutation. We present this case for its rarity and exuberance.

Oral presentation of 10 patients with Cowden syndrome

Cowden syndrome (CS) is an autosomal dominant genodermatosis that frequently affects several tissues with hamartomatous growth. The oral cavity is quite commonly involved with papillomatous lesions, which can be crucial to early diagnosis of this disease. In this series, 10 patients with a great diversity of manifestations associated with CS are presented, in whom oral papillomatosis was a constant and relevant finding to establish the diagnosis of CS. The role of the dentist in recognizing the oral lesions, the other diagnostic criteria, the risk for the development of malignancies, and the importance of lifetime follow-up are discussed.

Plasticity and mTOR: towards restoration of impaired synaptic plasticity in mTOR-related neurogenetic disorders

Objective. To review the recent literature on the clinical features, genetic mutations, neurobiology associated with dysregulation of mTOR (mammalian target of rapamycin), and clinical trials for tuberous sclerosis complex (TSC), neurofibromatosis-1 (NF1) and fragile X syndrome (FXS), and phosphatase and tensin homolog hamartoma syndromes (PTHS), which are neurogenetic disorders associated with abnormalities in synaptic plasticity and mTOR signaling. Methods. Pubmed and Clinicaltrials.gov were searched using specific search strategies. Results/Conclusions. Although traditionally thought of as irreversible disorders, significant scientific progress has been made in both humans and preclinical models to understand how pathologic features of these neurogenetic disorders can be reduced or reversed. This paper revealed significant similarities among the conditions. Not only do they share features of impaired synaptic plasticity and dysregulation of mTOR, but they also share clinical features—autism, intellectual disability, cutaneous lesions, and tumors. Although scientific advances towards discovery of effective treatment in some disorders have outpaced others, progress in understanding the signaling pathways that connect the entire group indicates that the lesser known disorders will become treatable as well.

Ras and Rap signaling in synaptic plasticity and mental disorders

The Ras family GTPases (Ras, Rap1, and Rap2) and their downstream mitogen-activated protein kinases (ERK, JNK, and p38MAPK) and PI3K signaling cascades control various physiological processes. In neuronal cells, recent studies have shown that these parallel cascades signal distinct forms of AMPA-sensitive glutamate receptor trafficking during experience-dependent synaptic plasticity and adaptive behavior. Interestingly, both hypo- and hyperactivation of Ras/ Rap signaling impair the capacity of synaptic plasticity, underscoring the importance of a "happy-medium" dynamic regulation of the signaling. Moreover, accumulating reports have linked various genetic defects that either up- or down-regulate Ras/Rap signaling with several mental disorders associated with learning disability (e.g., Alzheimer's disease, Angelman syndrome, autism, cardio-facio-cutaneous syndrome, Coffin-Lowry syndrome, Costello syndrome, Cowden and Bannayan-Riley-Ruvalcaba syndromes, fragile X syndrome, neurofibromatosis type 1, Noonan syndrome, schizophrenia, tuberous sclerosis, and X-linked mental retardation), highlighting the necessity of happy-medium dynamic regulation of Ras/Rap signaling in learning behavior. Thus, the recent advances in understanding of neuronal Ras/Rap signaling provide a useful guide for developing novel treatments for mental diseases.

Cowden disease: a review

Cowden disease is a genetically inherited disorder presenting with multiple hamartomatous and neoplastic lesions in various organs and tissues. We present a review of the diagnostic criteria, clinical presentation, genetics, and management of this condition.

Clinical and histopathological findings in Bannayan-Riley-Ruvalcaba syndrome

Bannayan-Riley-Ruvalcaba syndrome is a rare autosomal dominant genodermatosis with the classical triad of macrocephaly, genital lentiginosis, and intestinal polyposis. Characteristic mucocutaneous manifestations include vascular malformations, lipomatosis, speckled lentiginosis of the penis or vulva, facial verrucae-like or acanthosis nigricans-like lesions, and multiple acrochordons of the neck, axilla, and groin. We present a case of Bannayan-Riley-Ruvalcaba syndrome with macrocephaly, abnormal facies, lipoma, tender and painful arteriovenous hemangiomas, lymphangiokeratomas, musculoskeletal abnormalities, and localized myopathy. We also describe previously unreported findings, including peripheral neuropathy, punctate cystic changes in acral tubular bones, and enostosis of talus. Bannayan-Riley-Ruvalcaba syndrome needs recognition by dermatologists because affected patients may present with mucocutaneous and subcutaneous lesions that may simulate other dermatological disorders.

Testicular lipomatosis in Cowden's syndrome

Cowden's syndrome is either familial or sporadic and is associated with the predominantly postpubertal development of a variety of cutaneous, stromal and visceral neoplasms. The syndrome is associated with mutations of the PTEN gene and is closely related to Bannayan's syndrome in which macrocephaly and benign tumors, especially lipomas and hemangiomas are pathognomic. In PTEN knockout mice testicular tumors have been reported and for this reason we felt it prudent to examine the testes of our patients with genetically proven Cowden's syndrome. Seven of eight patients who underwent testicular ultrasound were found to have diffuse bilateral hyperechoic lesions. Four patients consented to testicular biopsy and on histological examination multiple foci of adipocytes were found within the testicular interstitium, with no evidence of dysplasia or preclinical malignancy. Immunohistochemical assessment of adipocytes suggested a stromal derivation without evidence of metaplasia from Leydig cells. In one case there was focal atrophy of seminiferous tubules, while in two others there was nodular periorchitis of the tunica albuginea. Biochemical evaluation of testicular function (luteinizing hormone, follicle-stimulating hormone, testosterone, sex hormone binding globulin and free androgen index), prostate-specific antigen and testicular tumor markers were normal, while seminal fluid analysis showed only minor abnormalities. The high incidence of testicular lipomatosis in our adult subjects suggests this to be an important diagnostic criterion for Cowden's syndrome.

Genetic testing for inherited colon cancer

The genes associated with each of the inherited syndromes of colon cancer have now been identified, and genetic testing is available for diagnosis. These syndromes include familial adenomatous polyposis, hereditary nonpolyposis colorectal cancer, Peutz-Jeghers syndrome, juvenile polyposis syndrome, and, possibly, Cowden's syndrome. Clinical genetic testing approaches have been developed for each of these syndromes and are now a part of accepted clinical care. Disease-causing mutations can be found in the majority of families affected with one of the inherited syndromes, and, most importantly, once a mutation is found in an index case of the family, relatives can be tested for the presence or absence of that mutation with near 100% accuracy. Cancer screening and management in syndrome families is then based on the results of genetic testing. For the physician to order and properly interpret genetic tests, a basic understanding of the types of mutations that lead to inherited disease and the methods for detecting them is vital. These issues will be presented. Additional clinical issues somewhat unique to genetic testing include genetic counseling and informed consent for genetic testing, both of which will also be reviewed. Often the most difficult aspect of genetic testing is deciding which patients and families should undergo the testing. Furthermore, this issue is quite specific for each of the syndromes. Thus, following presentation of general principles of selection for genetic testing, a detailed approach for identifying persons who should undergo testing for each of the individual syndromes will be given, together with relevant descriptions of the syndromes. Finally, the ongoing work to discover new and possibly more common but less penetrant colon cancer susceptibility genes that cause common familial colon cancer will be presented.

Doença de Cowden ou síndrome dos hamartomas múltiplos

Os autores descrevem um caso de doença de Cowden ou síndrome dos hamartomas múltiplos. Doença de transmissão autossômica dominante cuja tríade dermatológica clássica compõe-se de tricolemomas faciais múltiplos (hamartomas do infundíbulo folicular), fibromas orais e queratoses acrais benignas. Afeta múltiplos órgãos e é associada a várias neoplasias, tais como de mamas, tireóide, cólon e outras. Os autores apresentam um caso de paciente do sexo feminino em cujo exame físico notaram-se pápulas cor da pele na face, lesões papulosas na cavidade oral, mucosa jugal, língua plicata e hiperceratose palmoplantar puntata bilateral. História patológica pregressa de tireoidectomia subtotal por adenoma folicular.

Hamartomatous polyposis syndromes: genetic pathways

Hamartomatous polyposis syndromes are a group of clinically distinct but perhaps genetically related disorders in which the predominant finding is multiple hamartomatous polyps in the gastrointestinal tract. These syndromes are transmitted in an autosomal dominant fashion to offspring, but sporadic forms do exist in which the biological parents lack an identified germline mutation. Despite the nondysplastic histologic characteristics of their polyps, each hamartomatous syndrome carries an elevated risk for cancer at specific organ sites. Several genes have been identified as mutated in the germline from these syndromes, and they provide clues to the pathogenesis of the polyps and may explain some of the elevated cancer risk. Pathways involved in the hamartomatous syndromes include those of vascular endothelial growth factor, the transforming growth factor beta superfamily, and antagonizing the effects of Akt/protein kinase B.

Skin disorders and thyroid diseases

Thyroid disorders have a high prevalence in medical practice; they are associated with a wide range of diseases with which they may or may not share etiological factors. One of the organs which best show this wide range of clinical signs is the skin. This review is an attempt to approach most of the dermopathies reflecting several degrees of harmfulness, coming directly or indirectly from thyroid abnormalities, as well as to update current knowledge on the relationship between the thyroid and skin. We have proposed a primary classification of skin disorders, regarding thyroid involvement, into two main groups: 1) dermopathies associated with thyroid abnormalities, mainly with autoimmune thyroid diseases, like melasma, vitiligo, Sjogren's syndrome, alopecia, idiopathic hirsutism, pre-menstrual acne, bullous diseases, connective tissue diseases, hamartoma syndrome, atopy, leprosy and DiGeorge anomaly; and 2) dermopathies depending on the nature of the thyroid disorder, in which the evolution and outcome of the skin disorder depend on the thyroidal treatment in most cases, such as trophism and skin blood flow, myxedema, alopecia, onychodystrophy, hypo- and hyperhidrosis, xanthomas, intraepidermal bullae, carotenodermia, pruritus, flushing, pyodermitis, palmoplantar keratoderma, ecchymosis, etc. In some other cases, the skin disease which developed as a consequence of the thyroid abnormality can remain unaltered despite functional treatment of the thyroid problem, such as pretibial myxedema, thyroid acropachy and some cutaneous manifestations of multiple endocrine neoplasia types 2A and 2B.

Genital lentigines in a 6-year-old boy with a family history of Cowden's disease: clinical and genetic evidence of the linkage between Bannayan-Riley-Ruvacalba syndrome and Cowden's disease

BACKGROUND

In 1997, it was reported that a PTEN gene deletion, a common genetic mutation in Cowden's disease (CD), was identified in a patient with Bannayan-Riley-Ruvacalba (BRR), suggesting that the two diseases were allelic. However, the clinical overlap between the two diseases has largely remained unclear.

OBJECTIVE

To confirm the genetic and clinical association in a family segregating both CD and BRR.

METHODS

Clinical evaluation and genetic analysis using a denaturing gradient gel electrophoresis (DGGE), temporal temperature gradient electrophoresis (TTGE), and DNA sequencing techniques.

RESULTS

Our patient presents with typical BRR clinical manifestations, including multiple lentigines on his penis, while his mother presents with typical manifestations of CD, including multiple malignancies. Genetic analyses of leukocytes from the patient and his mother showed mutations in exon 8 that was identified as the presumably truncating mutation R335X.

CONCLUSION

This report provides clinical evidence that both BRR and CD are closely related and confirms the PTEN gene mutation in BRR and CD patients segregating in the same family, thus confirming the genetic linkage between the two genodermatoses.

Identification of a PTEN mutation in a family with Cowden syndrome and Bannayan-Zonana syndrome

Cowden syndrome (CS) and Bannayan-Zonana syndrome (BZS) are two inherited hamartoma syndromes characterized by distinct phenotypic features. Mutations in the PTEN gene have been identified in patients with CS and BZS, suggesting the presence of a common genetic basis. We describe a single kindred with individuals manifesting both CS and BZS phenotypes (CS/BZS overlap family) in which we have identified a novel mutation in PTEN by DNA sequencing. We have confirmed these results by means of restriction enzyme analysis. The presence of individuals with CS and BZS within the same family, and moreover the identification of identical PTEN gene mutations in these individuals, suggest that these two syndromes represent different phenotypic expressions of one disease. Furthermore, these findings imply that, like patients with CS, individuals with BZS should be monitored for the onset of malignancy.

Molecular genetics in pediatric dermatology

The field of pediatric dermatology continues to be enriched by the insights offered through molecular genetics. For some genetic skin disorders, including neurofibromatosis, tuberous sclerosis complex, and several forms of epidermolysis bullosa, genetic research has resulted in an evolving understanding of the relationship between genotype and phenotype, with the ability to predict some of the features of these disorders on the basis of the genetic defect. However, widespread use of molecular genetics for diagnostic testing of these disorders has not been possible because of genetic heterogeneity, limited availability, and reduced sensitivity. The appropriate use of genetic services is emphasized in this, the molecular era.