Multiple hamartoma syndrome (Cowden's disease) associated with renal cell carcinoma and primary neuroendocrine carcinoma of the skin (Merkel cell carcinoma)

Genomics of human congenital hydrocephalus

Congenital hydrocephalus (CH), characterized by enlarged brain ventricles, is considered a disease of pathological cerebrospinal fluid (CSF) accumulation and, therefore, treated largely by neurosurgical CSF diversion. The persistence of ventriculomegaly and poor neurodevelopmental outcomes in some post-surgical patients highlights our limited knowledge of disease mechanisms. Recent whole-exome sequencing (WES) studies have shown that rare, damaging de novo and inherited mutations with large effect contribute to ~ 25% of sporadic CH. Interestingly, multiple CH genes are key regulators of neural stem cell growth and differentiation and converge in human transcriptional networks and cell types pertinent to fetal neurogliogenesis. These data implicate genetic disruption of early brain development as the primary pathomechanism in a substantial minority of patients with sporadic CH, shedding new light on human brain development and the pathogenesis of hydrocephalus. These data further suggest WES as a clinical tool with potential to re-classify CH according to a molecular nomenclature of increased precision and utility for genetic counseling, outcome prognostication, and treatment stratification.

Early-onset renal cell carcinoma in PTEN harmatoma tumour syndrome

Individuals with PTEN hamartoma tumour syndrome (PHTS), including Cowden syndrome (CS), are susceptible to multiple benign hamartomas and an increased risk of cancer, particularly breast, endometrial, and thyroid. As a result, individuals undergo enhanced surveillance for early detection of these cancers. However, less commonly occurring cancers, such as colorectal and kidney, have insufficient guidelines for early detection. Currently, screening for kidney cancer via renal ultrasound begins at 40 years of age, because there were only rare cases of elevated risk in prospective series under 40. There have, however, been accumulating reports of kidney cancer in individuals with CS in their 30s, illustrating a need to lower the age of surveillance. We present additional evidence of renal cell carcinoma in two individuals with CS in their early twenties, and propose a reassessment of the abdominal surveillance in patients with PHTS. We propose biannual screening for kidney cancer beginning at 20 years of age.

Finding relationships among biological entities

Confusion over the concepts of “relationships” and “similarities” lies at the heart of many battles over the direction and intent of research projects. Here is a short story that demonstrates the difference between the two concepts: You look up at the clouds, and you begin to see the shape of a lion. The cloud has a tail, like a lion’s tale, and a fluffy head, like a lion’s mane. With a little imagination the mouth of the lion seems to roar down from the sky. You have succeeded in finding similarities between the cloud and a lion. If you look at a cloud and you imagine a tea kettle producing a head of steam and you recognize that the physical forces that create a cloud and the physical forces that produced steam from a heated kettle are the same, then you have found a relationship. Most popular classification algorithms operate by grouping together data objects that have similar properties or values. In so doing, they may miss finding the true relationships among objects. Traditionally, relationships among data objects are discovered by an intellectual process. In this chapter, we will discuss the scientific gains that come when we classify biological entities by relationships, not by their similarities.

PTEN Hamartoma Tumor Syndrome: A Clinical Overview

The phosphatase and tensin homolog (PTEN) hamartoma tumor syndrome (PHTS) is a grouping of related genetic disorders that has been linked to germline mutations in the PTEN gene. These disorders include Cowden syndrome (CS), Bannayan–Riley–Ruvalcaba syndrome, adult Lhermitte–Duclos disease, and autism spectrum disorders associated with macrocephaly. The majority of the clinical information available on PHTS, however, is related to individuals diagnosed with CS. There is still much to be learned about this disorder, since diagnostic criteria for CS were only established in 1996, before the identification of the PTEN gene, and were based primarily on features seen in cases reported in the existing literature. More recently, however, data from several large series of patients have shown that a number of the clinical features associated with PTEN mutations are either more or less common than previously reported. In addition, we now know that only about 30–35% of patients meeting clinical diagnostic criteria for Cowden syndrome actually have a detectable PTEN mutation. Thus, our understanding of PTEN-related diseases and their management has evolved significantly over time. The United States National Comprehensive Cancer Network (NCCN) has produced and regularly updates practice guidelines which include clinical diagnostic criteria as well as guidelines for PTEN testing and management of patients with mutations. This review will summarize the overall literature on PHTS as well as recent findings which are broadening our understanding of this set of disorders.

Concurrent Hairy Cell Leukemia and Metastatic Merkel Cell Carcinoma

Hairy cell leukemia (HCL) and Merkel cell carcinoma (MCC) are two rare malignancies with distinct cells of origin. HCL is a lymphoid malignancy of mature B cells, and MCC derives from neuroendocrine cell origin. HCL has a favorable prognosis with most patients achieving long-term remission and potential cure. In contrast, MCC is an aggressive malignancy affecting the skin and can metastasize quickly with a dismal prognosis. Immunocompromised patients, such as those with AIDS, posttransplant, and the elderly, have higher incidences than the general population, suggesting a possible immune mechanism. We report a case where a patient presented with HCL and metastatic MCC synchronously. This is the first reported case of these two rare malignancies occurring concurrently at initial presentation and may represent a role of immunosuppression in the pathogenesis of MCC.

Gynecologic Manifestations of Less Commonly Encountered Hereditary Syndromes

This review covers gynecologic manifestations that may occur in rare hereditary syndromes. Recent advances in disorders, such as hereditary leiomyomatosis, renal cell carcinoma syndrome and tuberous sclerosis complex, are discussed as well as lesions that occur in von Hippel-Lindau syndrome, nevoid basal cell carcinoma syndrome, Cowden syndrome, Ollier disease/Maffucci syndrome, and Carney complex. Characteristic clinicopathologic features of each of these syndromes are discussed with an emphasis on the key features that enable pathologists to identify patients at highest risk for these diseases.

Pulmonary atypical carcinoid in a patient with Cowden syndrome

Cowden syndrome is a phosphatase and tensin homologue on chromosome ten (PTEN) hamartoma tumour syndrome. The loss of function of the PTEN protein is associated with the risk of development and progression of several types of tumours, such as pulmonary neuroendocrine tumours and carcinoids. We present a 65-year old male non-smoker, who was diagnosed with Cowden syndrome and had a pulmonary tumour. He underwent wedge resection via video-assisted thoracoscopic surgery and was histopathologically diagnosed with an atypical carcinoid. To our knowledge, this is the first report on a pulmonary atypical carcinoid in a patient with Cowden syndrome. The present findings suggest a potential link between phosphoinositide-3 kinase/protein kinase B signalling in Cowden syndrome and the development of pulmonary neuroendocrine tumours, such as carcinoids.

Mosaic partial deletion of the PTEN gene in a patient with Cowden syndrome

Cowden syndrome is an autosomal dominant condition caused by pathogenic mutations in the phosphatase and tensin homolog (PTEN) gene. Only a small proportion of identified pathogenic mutations have been reported to be large deletions and rearrangements. We report on a female patient with a previous history of breast ductal carcinoma in situ who presented to our institution for management of gastrointestinal hamartomatous polyposis. Although several neoplastic predisposition syndromes were considered, genetic evaluation determined that the patient met clinical diagnostic criteria for Cowden syndrome. Array-based comparative genomic hybridization was performed and revealed a mosaic partial deletion of the PTEN gene. Follow-up clinical history including bilateral thyroid nodules, dermatological findings, and a new primary "triple-negative" adenocarcinoma of the contralateral breast are discussed. We highlight the need for recognition and awareness of mosaicism as it may provide an explanation for variable phenotypic presentations and may alter the genetic counseling risk assessment of affected individuals and family members.

Cowden disease and multicystic dysplastic kidney: increased risk of renal cancer?

Unilateral multicystic dysplastic kidney is one of the most frequently identified urinary tract abnormalities in children. Although it can be an isolated finding, it is often associated with other anomalies of the kidney and urinary tract. It has also been described in association with other multisystemic disorders of known genetic aetiologies. Cowden disease (CD) is a rare autosomal-dominant disorder with age-related penetrance characterized by benign and malignant hamartomatous lesions affecting derivatives of all three germ cell layers. Hamartomas can emerge in virtually every organ, but are mostly found in the skin and gastrointestinal tract. We report a 7-year-old patient presenting with unilateral multicystic dysplastic kidney and CD, a hitherto unknown association in paediatrics, which raises the question of an increased risk of renal cancer.

Epigenetics of kidney cancer and bladder cancer

This article focuses on the epigenetic alterations of aberrant promoter hypermethylation of genes, and histone modifications or RNA interference in cancer cells. Current knowledge of the hypermethylation of allele(s) in classical tumor suppressor genes in inherited and sporadic cancer, candidate tumor suppressor and other cancer genes is summarized gene by gene. Global and array-based studies of tumor cell hypermethylation are discussed. The importance of standardization of scoring of the methylation status of a gene is highlighted. The histone marks associated with hypermethylated genes, and the miRNAs with dysregulated expression, in kidney or bladder tumor cells are also discussed. Kidney cancer has the highest mortality rate of the genito-urinary cancers. There are management issues associated with the high recurrence rate of superficial bladder cancer, while muscle-invasive bladder cancer has a poor prognosis. These clinical problems are the basis for the translational application of gene hypermethylation in the diagnosis and prognosis of kidney and bladder cancer.

Acinic cell carcinoma of the retromolar trigone region: expanding the tumor phenotype in Cowden syndrome?

Cowden syndrome (CS) is a cancer predisposition syndrome caused by germline mutations in the PTEN tumor suppressor gene. It is associated with an increased risk of thyroid, breast and endometrial cancer but many manifestations can be found in the head and neck region, some of which are pathognomonic. Here we report a 35-year-old male referred by his dentist for evaluation of a lesion located near the retromolar trigone. Comprehensive clinical examination revealed papillomatous skin lesions, macrocephaly and gingival hypertrophy. Histopathological examination of the lesion showed an acinic cell carcinoma (ACC) of minor salivary gland origin. Analysis of the PTEN gene identified a germline R130Q mutation in exon 5, confirming the diagnosis of CS, but no loss of heterozygosity was seen in DNA extracted from tumor tissue. This is to our knowledge the first case describing an association of ACC of the minor salivary gland with a PTEN-gene related disorder. It emphasizes the importance of head and neck examination in these patients.

Cowden syndrome

BACKGROUND

Cowden syndrome is a rare genodermatosis charactarized by presence of multiple hamartomas. The aim of the study was to specify the clinical, therapeutic and prognostic aspects of Cowden syndrome.

CASES REPORT

Our study included 4 patients with Cowden syndrome, 2 males and 2 females between 14 and 46 years old. Clinical examination of the skin revealed facials papules (4 cases), acral keratosis (1 case), translucent keratotic papules (2 cases). Oral examination revealed papules (4 cases), papillomatosis (4 cases), gingival hypertrophy (4 cases) and scrotal tongue (2 cases). Investigations revealed thyroid lesions (2 cases), fibrocystic disease and lipoma of the breast in 1 case, "glycogenic acanthosis" (1 case), macrocephaly (2 cases), dysmorphic face (1 case) and lichen nitidus (1 case). Oral etretinate and acitretine were temporary efficient in 2 patients. Topical treatment with tretinoin lotion resulted in some improvement in cutaneous, but not mucosal lesions in one patient. No cancer was revealed.

CONCLUSION

The pathognomonic mucocutaneous lesions were found in all patients. However, no degenerative lesions have been revealed. A new association of Cowden syndrome with lichen nitidus was found. Treatment with oral retinoids was efficient on cutaneous lesions.

Cowden syndrome

Cowden syndrome (CS) is a rare inherited condition characterised by multiple hamartomas in a variety of tissues from all three embryonic layers. It is a cancer predisposition syndrome with an increased risk of developing malignancy in many tissues but especially breast, thyroid and endometrium. It is inherited in an autosomal dominant manner with ∼80% of patients having a germ-line mutation of the PTEN tumour suppressor gene. Presenting signs and symptoms are highly non-specific. Nevertheless clinicians should be able to recognise this syndrome so that patients may be screened for cancerous growths and afforded the opportunity to have genetic testing to assist them and their family members in making medical management decisions. We present a review of this unusual but important condition with particular emphasis on the diagnostic criteria, clinical features, genetics, management and surveillance.

Updated Review of the Pathogenesis and Management of Merkel Cell Carcinoma

Background:

Merkel cell carcinoma is a rare, aggressive, malignant cutaneous tumor of the elderly or immunosuppressed individuals that usually appears on sun-exposed areas of the body. Its pathogenesis is still debated, and, currently, no standardized treatment exists.

Objective:

To provide a current updated review of the most relevant data concerning the pathogenesis and management of Merkel cell carcinoma.

Methods:

Using relevant MeSH terms, we performed a review of the literature on these subjects from 1980 to June 2009.

Results and Conclusion:

The current management of Merkel cell carcinoma is based on surgical excision as the majority of patients present with localized disease, whereas up to 30% have regional lymph node metastases. In these cases, the best outcome is achieved with multidisciplinary management that includes radiotherapy. Chemotherapy is part of the treatment in advanced cases and is mandatory for distant metastatis. Given that a recent work showed the presence of a previously unknown polyomavirus, which the authors called Merkel cell polyomavirus, the therapeutical approach to Merkel cell carcinoma could be reconsidered in the future.

Renal cell carcinoma

Renal Cell Carcinoma (RCC) has the highest mortality rate of the genitourinary cancers and the incidence of RCC has risen steadily. If detected early, RCC is curable by surgery although a minority are at risk of recurrence. Increasing incidental detection and an ageing population has led to active surveillance as an option for patients with small renal masses. RCC is heterogeneous and comprises several histological cell types with different genetics, biology and behavior. The identification of the genes predisposing to inherited syndromes with RCC has provided much of our knowledge of the molecular basis of early sporadic RCC. Many of the oncogenes and tumor suppressor genes that are mutated leading to pathway dysregulation in RCC remain to be elucidated. Global studies of copy number, gene sequencing, gene expression, miRNA expression and gene methylation in primary RCC will lead towards this goal. The natural history of RCC indicated by candidate precursor lesions, multifocal or bilateral disease, growth rate of small renal masses under surveillance, and high risk populations provide insight into the behavior of this disease. The use of molecular markers for early detection and prognosis merits more attention with ongoing advances in omics technologies. This review focuses on early RCC, that is disease confined within the renal capsule.

Cowden syndrome: a critical review of the clinical literature

Cowden syndrome (CS) is a multi-system disease involving hamartomatous overgrowth of tissues of all three embryonic origins and increased risks for thyroid, breast and possibly other cancers. Benign breast, thyroid, uterine and skin lesions are also common. Approximately 80% of patients with CS have an identifiable germline mutation in the PTEN gene. The majority of the existing data on the frequencies of component clinical features have been obtained from compilations of case reports in the literature, many of which predate the establishment in 1996 of consensus diagnostic criteria. Many of these reports also suffer from ascertainment bias which emphasized the dermatologic features of the disease. This paper presents an overview of Cowden syndrome focusing on a critical evaluation of the major literature on the component cancers, benign features, and molecular findings in CS, noting the limitations of the published data.

Cowden syndrome: a critical review of the clinical literature

Cowden syndrome (CS) is a multi-system disease involving hamartomatous overgrowth of tissues of all three embryonic origins and increased risks for thyroid, breast and possibly other cancers. Benign breast, thyroid, uterine and skin lesions are also common. Approximately 80% of patients with CS have an identifiable germline mutation in the PTEN gene. The majority of the existing data on the frequencies of component clinical features have been obtained from compilations of case reports in the literature, many of which predate the establishment in 1996 of consensus diagnostic criteria. Many of these reports also suffer from ascertainment bias which emphasized the dermatologic features of the disease. This paper presents an overview of Cowden syndrome focusing on a critical evaluation of the major literature on the component cancers, benign features, and molecular findings in CS, noting the limitations of the published data.

Lhermitte-Duclos disease associated with Cowden syndrome

Lhermitte-Duclos disease or dysplastic gangliocytoma of the cerebellum, is a rare cerebellar lesion, which can cause mass effects in the posterior fossa. It may occur sporadically, or in association with Cowden syndrome. Cowden syndrome or multiple hamartoma-neoplasia syndrome, is an uncommon autosomal dominant condition characterized by mucocutaneous lesions and systemic malignancies. We report two patients with Lhermitte-Duclos disease and associated Cowden syndrome. The clinical, radiological and histopathological features and management strategies of this rare disease complex are discussed.

Dermatologic aspects of thyroid disease

Thyroid disorders commonly have dermatologic manifestations. The purpose of the present chapter is to review and emphasize potential clinical dermatologic findings that can occur with Graves' disease, hypothyroidism and thyroid cancer. In autoimmune diseases such as Graves' disease and Hashimoto's thyroiditis the skin manifestations may be related to either thyroid hormone levels themselves or to the associated T and/or B cell abnormalities. Thyroid cancer may be associated with various syndromes that could have significant skin manifestations.

Nuclear Pedigree Criteria for the Identification of Individuals Suspected to be at Risk of an Inherited Predisposition to Renal Cancer

Renal clear cell carcinomas represent about 3% of all visceral cancers and account for approximately 85% of renal cancers in adults. Environmental and genetic factors are involved in the development of renal cancer. Although to date there are 19 hereditary syndromes described in which renal cell cancer may occur, only four syndromes with an unequivocal genetic predisposition to renal cell carcinoma have been identified: VHL syndrome (mutations in the VHL gene), hereditary clear cell carcinoma (translocations t(3:8), t(2:3)), hereditary papillary carcinoma (mutations in the MET protooncogene) and tuberous sclerosis (mutations in the TSC1 and TSC2 genes). Little is known genetically about the other forms of familial renal cell cancer. Since there is a growing awareness about the necessity of early intervention, clinical criteria have been developed that aid in the identification of hereditary forms of renal cancer. The aim of the current study was to identify minimal inclusion criteria so that nuclear pedigree families can be ascertained for risk assessment and/or kidney tumour screening. The results reveal that inclusion features described herein, such as (a) renal clear cell cancer diagnosed before 55 years of age, and (b) renal clear cell cancer and gastric cancer or lung cancer among first degree relatives, are useful in identifying suspected hereditary clear cell renal cancer patients.

The hamartomatous polyposis syndromes: a clinical and molecular review

Inherited forms of gastrointestinal cancer have been a major focus of study and advancement over the past decade. Familial adenomatous polyposis and hereditary nonpolyposis colon cancer are the two most common heritable colon cancer syndromes. Inherited polyposis syndromes are characterized by the dominant type of polyp (whether adenomatous or hamartomatous) present and by the polyp's location within the gastrointestinal tract. The hamartomatous polyposis syndromes are characterized by an overgrowth of cells native to the area in which they normally occur. They represent a small but appreciable number of the gastrointestinal inherited cancer predisposition syndromes; it is now known that many of these syndromes carry a substantial risk for developing colon cancer as well as other gastrointestinal and pancreatic cancers. Patients afflicted with these syndromes are also at significant risk for extraintestinal malignancies. Seven inherited hamartomatous polyposis syndromes have been described: familial juvenile polyposis syndrome, Cowden's syndrome, Bannayan-Ruvalcaba-Riley syndrome, Peutz-Jeghers syndrome, basal cell nevus syndrome, neurofibromatosis 1, and multiple endocrine neoplasia syndrome 2B. Hereditary mixed polyposis syndrome is a variant of juvenile polyposis characterized by both hamartomatous and adenomatous polyps. The hamartomatous syndromes occur at approximately 1/10th the frequency of the adenomatous syndromes and account for <1% of colorectal cancer in Northern America. While the diagnosis of these inherited syndromes is primarily clinical, genetic testing is now available for all six syndromes. However, there are a significant number of spontaneous mutations seen in each of the syndromes. The management of these patients necessitates a coordinated multidisciplinary approach. The purpose of this review is to characterize the clinical and pathological features of these syndromes and to review the targets of cancer surveillance. The molecular alterations responsible for the inherited hamartomatous polyposis syndromes will also be discussed.

Cowden disease: CT findings in three patients

Cowden disease, also known as multiple hamartoma syndromes, is an autosomal dominant disease characterized by numerous benign mucocutaneous tumors, hamartomas of multiple organs, and malignancies of the breast and thyroid. In this report, we present the computed tomographic findings in three patients with Cowden disease. In addition to the classic findings, the patients were diagnosed with spinal neurinoma (n=1), meningioma (n=1), and hepatic hemangioma (n=3). We also review current clinical and genetic concepts that unify Cowden disease.

Hereditary cancer syndromes of the skin

Hereditary cancer syndromes are a group of disorders characterized by a genetic susceptibility to the development of malignant tumors. Multiple cancers in the family or an abnormally early onset for the given cancer may suggest an underlying inherited predisposition. Awareness of their associated dermatologic manifestations can facilitate early detection of risk for neoplasms. This article provides an update on the clinical features, diagnostic criteria, and the use of genetic analysis in the detection of causative mutations of those hereditary cancer syndromes with cutaneous manifestations.

Association between Cowden syndrome and Lhermitte-Duclos disease

BACKGROUND

The authors describe 2 cases of dysplasic gangliocytoma of the cerebellum or Lhermitte-Duclos disease revealing Cowden disease or multiple hamartoma neoplasia syndrome. Cowden disease is a rare autosomal dominant disorder, now considered as a phakomatosis. Nevertheless, relationships between both conditions still remain unclear, since Lhermitte-Duclos disease can also be sporadic.

CASE REPORTS

Two patients, 25 and 27 years old, were admitted to the emergency department for an acute intracranial hypertension. In both cases, magnetic resonance imaging (MRI) scan showed a mass in the cerebellar hemisphere. Pathological examination of surgical resection specimens concluded Lhermitte-Duclos disease. Because of the patients' previous personal and familial medical history, Cowden disease was suspected and confirmed by mutational analysis of the phosphatase and tensin homolog (PTEN) gene. In the first case, a nonsense punctual mutation in exon 8 was found. In the second one, a mutation was revealed in the exon 5, a mutational hot spot encoding the phosphatase catalytic core motif.

CONCLUSION

Lhermitte-Duclos disease and Cowden disease can be associated. Germline mutations of PTEN gene are known to be implicated in Cowden disease. This gene, located at chromosome 10q23-3, is a tumor suppressor gene that encodes a protein with phosphatase activity. To date, more than 80 mutations have been reported in Cowden disease. When the diagnosis of either one of these two disorders is established, it is imperative to search for the other one to detect early malignant lesions that occur in Cowden disease. Finally, a long-term follow up of the patient is required and a thorough familial screening is necessary.

Bannayan-Riley-Ruvalcaba syndrome: further delineation of the phenotype and management of PTEN mutation-positive cases

Bannayan-Riley-Ruvalcaba syndrome (BRRS) is characterised by macrocephaly, intestinal hamartomatous polyps, lipomas, pigmented maculae of the glans penis, developmental delay and mental retardation. The syndrome follows an autosomal dominant pattern of inheritance. In 1997 reports on two BRRS patients with a deletion at 10q23.2-q24.1 were published. In the same year, the first two families with BRRS and a mutation of the PTEN gene were reported. Mutations in the PTEN gene have also been demonstrated in patients with Cowden syndrome (CS), which shows partial clinical overlap with BRRS, and in families with cases both of BRRS and CS. PTEN mutation positive BRRS and CS are likely to be different phenotypic presentations of the same syndrome. If BRRS and CS are one single condition, the question arises whether patients with BRRS should be screened for malignant tumours, since patients with Cowden syndrome have an increased risk of breast, endometrial, thyroid and renal cancer. We present two isolated cases and one family and confirm that BRRS and CS are allelic. Furthermore, we review the PTEN mutation positive BRRS cases, to further delineate the phenotype and to compare the cases with a genomic deletion with the cases with a point mutation. We recommend offering BRRS cases with a mutation in PTEN the same surveillance protocol for (malignant) tumours as is currently recommended for CS. In addition, we propose a yearly haemoglobin test from early infancy for the early detection of intestinal hamartomas, which are likely to give severe complications, especially in BRRS cases.

[Benign and malignant pulmonary tumors in childhood]

Pulmonary tumors in children are rare. Nevertheless, there are besides malign primary neoplasms and metastases also some benign tumors that the radiologist should know. The identification of some tumors is difficult, since some of them may mimic pulmonary inflammation. The first diagnostic tool is chest radiography. After that, a CT with contrast medium should be performed, if possible a multislice-CT (MSCT). Identification of mediastinal structures is best with MRI.

Evaluation and management of a solitary thyroid nodule in a child

Although an uncommon clinical entity, a pediatric patient with a solitary thyroid nodule requires a thorough assessment because of the increased incidence of thyroid carcinoma in this population. In the future, one may expect the widespread clinical use of genetic markers in identifying children, who are at risk for, or who have developed, thyroid carcinomas, with the hopes that these molecular markers will lead to the prevention, or earlier detection and cure, of these malignancies.

[Cowden's disease in an adolescent]

Cowden's disease is an autosomal dominantly inherited syndrome characterized by mucocutaneous lesions and multiple hamartomas. We report here a 12 years-old boy case with craniomegally, intestinal polyps, epilepsy and multiadenomatous goiter. All the lesions were beginnings. The predisposing genetic defect has been assignated to chromosomal 10 (PTEN-gene mutation). A long term follow-up is necessary because of the risk of malignancies.

Merkel Cell Carcinoma: Important Aspects of Diagnosis and Management

Merkel cell carcinoma (MCC) is a highly aggressive primary neuroendocrine tumor. It is suggested in the literature that postoperative radiotherapy may decrease local recurrence and improve overall survival. The purpose of this retrospective review was to determine our experience and review the literature on this aggressive malignancy. Charts of ten patients with MCC seen between 1985 and 1997 were reviewed to obtain clinicopathological data. Eight patients were male with a mean age of 72 years (range 49–90). The head and neck was the most common site, affecting 50 per cent of patients. All patients had primary excisions with documented negative margins. Pathological size ranged from 10 to 40 mm. Initial pathological diagnosis was lymphoma in three cases requiring immunohistochemistry for cytokeratin and neuron-specific enolase for definitive diagnosis. Lymphatic invasion was noted in three patients but only one of these patients had clinical lymph node involvement. The mean follow-up was 54 months (range 6–114) with an 80 per cent one-year survival and 30 per cent 2-year survival. Postoperative radiotherapy was administered to five patients. Of these three died with evidence of both local and distant recurrence. This small retrospective review highlights important points in the management of MCC including pathological diagnosis and benefits of adjuvant radiation therapy.

[Neuroendocrine renal tumor. An unusual case. Review of the literature]

The neuroendocrine renal tumors are of extremely strange presentation. We present a review of the literature published on this pathology.

Frequent allelic loss at 10q23 but low incidence of PTEN mutations in Merkel cell carcinoma

Merkel cell carcinoma (MCC) is a rare, highly metastatic skin tumor of neuroectodermal origin. The disease shares clinical and histopathological features with small cell lung carcinoma (SCLC). The genetic mechanisms underlying the development and tumor progression of MCC are poorly understood. We recently showed by comparative genomic hybridization (CGH) that the pattern of chromosomal abnormalities in MCC resembles that of SCLC. One of the most frequently observed losses involved the entire chromosome 10 or partial loss of the chromosome 10 long arm (33% of examined MCC cases). The PTEN tumor-suppressor gene has been mapped to 10q23.3 and was shown to be mutated in a variety of human cancers including SCLC. Germline PTEN mutations have been observed in familial predisposing cancer syndromes including Cowden disease. Interestingly, an association between Cowden syndrome and Merkel cell carcinoma has been reported. To study the possible role of PTEN in MCC oncogenesis, loss of heterozygosity (LOH) analysis for the 10q23 region was performed on 26 MCC tumor samples from 23 MCC patients. The PTEN locus was deleted in 9 of 21 (43%) informative MCC tumor samples [7 of 18 (39%) MCC patients]. Despite this high frequency of LOH at 10q23, mutation and homozygous deletion screening of the PTEN gene revealed only one tumor with a nonsense mutation and a second with a homozygous deletion of exon 9. These data suggest that either alternative mechanisms lead to inactivation of the PTEN gene or that other tumor-suppressor genes at chromosome 10 are implicated in the development of MCC.

Cowden's syndrome (multiple hamartoma and neoplasia syndrome): diagnostic dilemmas in three cases

Cowden's syndrome is a multisystem disease inherited as an autosomal dominant trait with incomplete penetrance and variable expression. The disease has typical oral manifestations which often precede more systemic involvement, and the dental professional is therefore well placed to institute a regime of regular checks to ensure early treatment of any neoplasms which may occur. However, since not all of the classical signs are present in all patients, diagnosis may be difficult. The case report of a patient with most of the features of Cowden's syndrome is presented and features compared with two other possible cases.

Cowden disease and Lhermitte-Duclos disease: characterization of a new phakomatosis

OBJECTIVE

Lhermitte-Duclos disease, or dysplastic gangliocytoma of the cerebellum, is an unusual hamartomatous lesion that can cause progressive mass effects in the posterior fossa. Cowden disease, or multiple hamartoma-neoplasia syndrome, is a rare autosomal dominant disorder characterized by mucocutaneous hamartomas and high incidences of systemic malignancies. We recently treated a patient with manifestations of both Lhermitte-Duclos disease and Cowden disease, and we were intrigued by the occurrence of these two rare disorders in the same patient. The purpose of the present study was to examine the nature of the association between Lhermitte-Duclos disease and Cowden disease.

METHODS

The records for all patients who had been diagnosed at our institution as having Lhermitte-Duclos disease were reviewed, to determine whether these patients also exhibited manifestations of Cowden disease. Data were obtained from multiple sources, including patient interviews, correspondence with treating physicians, and chart reviews.

RESULTS

During the past 40 years, five patients were diagnosed at Case Western Reserve University as having Lhermitte-Duclos disease. All five patients exhibited manifestations of Cowden disease. Before this review, Cowden disease had not been diagnosed for three of the patients. In our most recent case, the diagnoses of both disorders were established preoperatively. That patient was observed to have a deletion in the critical portion of Exon 5 of the PTEN gene, the gene associated with Cowden disease.

CONCLUSION

Inclusion of Lhermitte-Duclos disease in the Cowden disease spectrum suggests that Cowden disease is a true phakomatosis, with hamartomas arising from cutaneous and neural ectoderm. Recent advances in molecular genetics may help to refine the current descriptive classification of the phakomatoses. The association between Lhermitte-Duclos disease and Cowden disease has been under-recognized and under-reported. Recognition of this association has direct clinical relevance, because diligent long-term follow-up monitoring of individuals with Lhermitte-Duclos disease and Cowden disease may lead to the early detection of malignancy.

Unusual types of thyroid neoplasms

This article discusses several unusual forms of primary thyroid neoplasms. The TCV of PTC and insular thyroid carcinoma appears to have a more aggressive clinical behavior than DTC in most patient groups and may respond to thyroid hormone suppression and radioiodine. Anaplastic thyroid carcinoma, which may develop from differentiated thyroid tumors, has a poor prognosis which may be altered by surgery and radiation therapy but not typically by radioiodine and thyroid hormone suppression. Primary squamous cell carcinoma of the thyroid is an unusual entity that may be associated with a clinical syndrome that includes leukocytosis, fever, and hypercalcemia. Primary thyroid lymphoma is frequently associated with Hashimoto's thyroiditis and should be considered especially in older patients with rapidly enlarging thyroid masses. Although there are no studies assessing this issue, it seems reasonable that patients who have undergone thyroidectomy for neoplasms of thyroid cells that are poorly differentiated and do not concentrate radioiodine (e.g., squamous cell, anaplastic) should receive sufficient thyroid hormone suppression, if tolerated, to reduce TSH (third-generation assay) to approximately 0.1 to 0.3 mu U/mL, because TSH may be a growth factor. If, however, the tumor concentrates or responds to radioiodine, suggesting more differentiated cells (e.g., TCV, insular carcinoma), the target TSH level (third-generation assay) should range from 0.01 to 0.1 mu U/mL, as tolerated. Patients with primary thyroid neoplasms arising from cells other than thyrocytes (e.g., lymphoma) can be maintained at a TSH level of 0.5 to 1.5 mu U/mL. Our conclusions and analyses are often based upon small, retrospective, poorly controlled reports, and further studies are required to allow a better understanding of the evaluation and treatment of these neoplasms.

Merkel cell carcinoma. Diagnosis and treatment

BACKGROUND

Merkel cell carcinoma is an uncommon malignancy of the skin that often portends a poor prognosis. Since its first description by Toker in 1972, a plethora of case reports and articles regarding the etiopathogenesis and treatment have been published spanning multiple medical and surgical disciplines. Much confusion still exists regarding the diagnosis and treatment of this ominous tumor.

OBJECT

Through extensive review of the medical, surgical, and pathological literature, to collate the observations of multiple investigators and summarize these findings.

METHODS

Articles from journals of multiple subspecialties were carefully reviewed with particular emphasis placed on epidemiology, prognosis, histology, immunohistochemistry, electron microscopy, tumor origin, treatment, and work-up of Merkel cell carcinoma.

RESULTS

Merkel cell carcinoma is an aggressive malignant neoplasm. Local recurrence develops in 26-44% of patients despite therapy. Up to three-fourths of patients eventually develop regional nodal metastases with distant metastases occurring in one-third of all patients. Reported overall 5-year survival rates range from 30% to 64%.

CONCLUSION

Treatment recommendations unfortunately are based more on anecdotal than scientific data because of the rarity of the tumor and its recognized high risk. Most authors recommend wide local excision of the primary lesion and regional lymph node resection if lymph nodes are palpable followed by x-irradiation of both the postsurgical bed and lymph node basin. The role of elective lymph node resection in the absence of clinically positive nodes remains controversial.

Lhermitte-Duclos disease and Cowden's syndrome in an adolescent patient. Case report

Recent reports of seven cases of Lhermitte-Duclos disease occurring in adult patients with Cowden's syndrome (multiple hamartoma syndrome) strongly suggest that Lhermitte-Duclos disease is one of the types of neoplasia that characterize this syndrome. A case of Lhermitte-Duclos disease is reported in a 16-year-old girl with craniomegaly, choroidal hamartoma, and conjunctival papilloma of the right eye, and a history of bilateral multinodular adenomatous goiter and cystic hygroma. These findings strongly suggest a diagnosis of Cowden's syndrome. Although the syndrome traditionally has been defined by mucocutaneous criteria, it typically also involves hamartomas and neoplasia of internal organs, most commonly in the thyroid, breast, and female genitourinary tract. Because the mucocutaneous features may develop several decades after birth, the present case both supports the previously reported association between Lhermitte-Duclos disease and Cowden's syndrome and highlights the need for long-term follow-up monitoring of a pediatric patient with Lhermitte-Duclos disease because of the risk of malignancies associated with Cowden's syndrome.

Cowden's disease: report of the first case in a Chinese

A 19-year-old Chinese female presenting mucocutaneous manifestations including facial trichilemmomas, oral papillomatosis, and acral keratosis was diagnosed, according to the criteria proposed by Salem and Steck, as a definite case of Cowden's disease, although no members of her family were affected. The cutaneous reticulohistiocytic granuloma and congenital nystagmus of eyes that occurred in this case were new combinations in the syndrome. To the best of our knowledge, this is the first documented case of Cowden's disease in a Chinese.