Brain morphological analysis in PTEN hamartoma tumor syndrome.

PTEN hamartoma tumor syndrome (PHTS) is a spectrum of hereditary cancer syndromes caused by germline mutations in PTEN. PHTS is of high interest, because of its high rate of neurological comorbidities including macrocephaly, autism spectrum disorder, and intellectual dysfunction. Since detailed brain morphology and connectivity of PHTS remain unclear, we quantitatively evaluated brain magnetic resonance imaging (MRI) in PHTS. Sixteen structural T1-weighted and 9 diffusion-weighted MR images from 12 PHTS patients and neurotypical controls were used for structural and high-angular resolution diffusion MRI (HARDI) tractography analyses. Mega-corpus callosum was observed in 75%, polymicrogyria in 33%, periventricular white matter lesions in 83%, and heterotopia in 17% of the PHTS participants. While gyrification index and hemispheric cortical thickness showed no significant differences between the two groups, significantly increased global and regional brain volumes, and regionally thicker cortices in PHTS participants were observed. HARDI tractography showed increased volume and length of callosal pathways, increased volume of the arcuate fasciculi (AF), and increased length of the bilateral inferior longitudinal fasciculi (ILF), bilateral inferior fronto-occipital fasciculi (IFOF), and bilateral uncinate fasciculus. A decrease in fractional anisotropy and an increased in apparent diffusion coefficient values of the AF, left ILF, and left IFOF in PHTS.

Lhermitte-Duclos Disease and Cowden Syndrome: A Case Report and Literature Review

Lhermitte-Duclos disease (LDD), also known as dysplastic gangliocytoma of the cerebellum, is a rare, usually benign, slow-growing tumor, that commonly affects patients aged 30 to 50 years-old. The manifestations of dysplastic cerebellar gangliocytoma are nonspecific and are related both to the mass effect produced by its growth and to the location of the lesion. Cerebellar symptoms such as ataxia are often present. In 40% of cases, the tumor is associated with Cowden syndrome, which is part of a group ofgenetic disorders called polypoid hamartoma complex. In this case report, the patient presented expansive lesion in the posterior fossa, compatible with LDD, associated with macrocephaly. These findings are consideredmajor criteria for Cowden syndrome. When together, they confirm the diagnoses. To our knowledge, this is the first report of the association of LDD and Cowden syndrome in Brazil.

PTEN Hamartoma tumor syndrome in childhood: A review of the clinical literature.

PTEN hamartoma tumor syndrome (PHTS) is a highly variable autosomal dominant condition associated with intellectual disability, overgrowth, and tumor predisposition phenotypes, which often overlap. PHTS incorporates a number of historical clinical presentations including Bannayan-Riley-Ruvalcaba syndrome, Cowden syndrome, and a macrocephaly-autism/developmental delay syndrome. Many reviews in the literature focus on PHTS as an adult hamartoma and malignancy predisposition condition. Here, we review the current literature with a focus on pediatric presentations. The review starts with a summary of the main conditions encompassed within PHTS. We then discuss PHTS diagnostic criteria, and clinical features. We briefly address rarer PTEN associations, and the possible role of mTOR inhibitors in treatment. We acknowledge the limited understanding of the natural history of childhood-onset PHTS as a cancer predisposition syndrome and present a summary of important management considerations.

A family with PTEN mutations with malignancy and an unusually high number of offspring with autism spectrum disorder: a case report.

BACKGROUND: Cowden's syndrome (OMIM:158350), a rare genetic disorder (incidence ~ 1:250,000), is caused by mutations of the tumor suppressor gene PTEN. In this report, we describe clinical manifestations of a 56-year-old patient diagnosed with Cowden's syndrome and his family with PTEN mutations. The family has an unusually high number of offspring with autism spectrum disorder. CASE PRESENTATION: Except for his 80-year-old Caucasian father, all of our index case's living Caucasian kindred (three children, brother, and nephew) had PTEN mutations and macrocephaly. Prior to genetic testing, his mother and sister died of breast cancer at 42 and 38 years old, respectively. After PTEN mutation was identified, our patient underwent complete thyroidectomy (histology showing micropapillary carcinoma) and right nephrectomy for renal cell carcinoma. All of his three children (13-year-old son, 11- and 8-year-old daughters) have been diagnosed with autism spectrum disorder. His son and brother underwent total thyroidectomy. His nephew had thyroid nodules. Management of Cowden's syndrome requires clinical examinations and investigations every 6 to 12 months from 18 years old or 5 years before the family's earliest age of cancer diagnosis and should focus on all clinical manifestations associated with PTEN mutations to identify early abnormal changes in skin, breasts, thyroid, endometrium, gut, and kidneys. Input from specialists across different disciplines is necessary. CONCLUSIONS: We describe a man and his family with PTEN mutations who have increased risk of cancers and an unusually high number of offspring with autism spectrum disorder. Early recognition and close surveillance are vital in order to provide treatment and early screening for asymptomatic at-risk relatives.

Childhood Lhermitte-Duclos Disease Progressing to Medulloblastoma in Bilateral Cerebellar Hemispheres: Report of Unusual Case.

BACKGROUND: Lhermitte-Duclos disease is an extremely rare pathologic entity characterized by a cerebellar mass composed of enlarged cerebellar folia containing abnormal ganglion cells. This entity usually presents in young and middle-aged adults and rarely in children. There is no study in the literature analyzing the long-term clinical course of this disease to assess the behavior primarily because of its rarity. CASE DESCRIPTION: We present our experience with a 7-year-old patient of Lhermitte-Duclos disease who was followed up for 5 years and found to have progressed to bilateral World Health Organization grade IV medulloblastoma. This case denotes the malignant potential of this rare disorder. CONCLUSIONS: LDD is seen rarely and demands a high degree of suspicion in patients presenting with cerebellar mass and/or imaging characteristics. It is prudent to keep these patients in close follow-up for early detection of malignant transformation.

Hemimegalencephaly with Bannayan-Riley-Ruvalcaba syndrome.

Hemimegalencephaly is known to occur in Proteus syndrome, but has not been reported, to our knowledge, in the other PTEN mutation-related syndrome of Bannayan-Riley-Ruvalcaba. Here, we report a patient with Bannayan-Riley-Ruvalcaba syndrome who also had hemimegalencephaly and in whom the hemimegalencephaly was evident well before presentation of the characteristic manifestations of Bannayan-Riley-Ruvalcaba syndrome. An 11-year-old boy developed drug-resistant focal seizures on the fifth day of life. MRI revealed left hemimegalencephaly. He later showed macrocephaly, developmental delay, athetotic quadriplegic cerebral palsy, and neuromuscular scoliosis. Freckling of the penis, which is characteristic of Bannayan-Riley-Ruvalcaba syndrome, was not present at birth but was observed at 9 years of age. Gene analysis revealed a c.510 T>G PTEN mutation. This patient and his other affected family members, his father and two siblings, were started on the tumour screening procedures recommended for patients with PTEN mutations. This case highlights the importance of early screening for PTEN mutations in cases of hemimegalencephaly not otherwise explained by another disorder, even in the absence of signs of Proteus syndrome or the full manifestations of Bannayan-Riley Ruvalcaba syndrome.

Broad spectrum of neuropsychiatric phenotypes associated with white matter disease in PTEN hamartoma tumor syndrome.

White matter lesions have been described in patients with PTEN hamartoma tumor syndrome (PHTS). How these lesions correlate with the neurocognitive features associated with PTEN mutations, such as autism spectrum disorder (ASD) or developmental delay, has not been well established. We report nine patients with PTEN mutations and white matter changes on brain magnetic resonance imaging (MRI), eight of whom were referred for reasons other than developmental delay or ASD. Their clinical presentations ranged from asymptomatic macrocephaly with normal development/intellect, to obsessive compulsive disorder, and debilitating neurological disease. To our knowledge, this report constitutes the first detailed description of PTEN-related white matter changes in adult patients and in children with normal development and intelligence. We present a detailed assessment of the neuropsychological phenotype of our patients and discuss the relationship between the wide array of neuropsychiatric features and observed white matter findings in the context of these individuals.

Characterization of cryptic splicing in germline PTEN intronic variants in Cowden syndrome.

Germline mutations in the tumor-suppressor gene PTEN predispose to subsets of Cowden syndrome (CS), Bannayan-Riley-Ruvalcaba syndrome, and autism. Evidence-based classification of PTEN variants as either deleterious or benign is urgently needed for accurate molecular diagnosis and gene-informed genetic counseling. We studied 34 different germline PTEN intronic variants from 61 CS patients, characterized their PTEN mRNA processing, and analyzed PTEN expression and downstream readouts of P-AKT and P-ERK1/2. While we found that many mutations near splice junctions result in exon skipping, we also identified the presence of cryptic splicing that resulted in premature termination or a shift in isoform usage. PTEN protein expression is significantly lower in the group with splicing changes while P-AKT, but not P-ERK1/2, is significantly increased. Our observations of these PTEN intronic variants should contribute to the determination of pathogenicity of PTEN intronic variants and aid in genetic counseling.

Frequent vomiting attacks in a patient with Lhermitte-Duclos disease: a rare pathophysiology of cerebellar lesions?

Lhermitte-Duclos disease (LDD) is a neurological disease caused by a hamartomatous lesion in the cerebellum. Clinically, LDD is commonly associated with progressive space-occupying lesion effects in the posterior fossa, increasing intracranial pressure, occlusive hydrocephalus, and focal neurological deficits of adjacent structures. The authors report the case of a 10-year-old boy with LDD who had been suffering from vomiting attacks (VAs). These VAs had been brief in duration but extremely frequent, and they had been resistant to antiemetic drugs since the early postnatal period. Magnetic resonance imaging at 8 months of age revealed a right cerebellar lesion with very little space-occupying lesion effect, but the causal relationship with VAs was not evident at that point, because no clinical symptoms or signs other than vomiting were suggestive of increased intracranial pressure. The VAs were initially diagnosed as autonomic ataxia and had been treated with antiemetic drugs for approximately 10 years, but the patient's symptoms were not improved at all in frequency or duration. He developed convulsive seizures at 9 years of age and was referred to the authors' epilepsy center. The VAs were initially speculated to represent an aspect of seizures, but antiepileptic agents proved ineffective against this symptom despite remission of convulsive seizures. Video-electroencephalography monitoring did not show any evolving ictal patterns associated with the vomiting. Careful reevaluation of MRI studies revealed that the cerebellar lesion was fused with the cerebellum, middle and inferior cerebellar peduncles, and dorsolateral medulla oblongata with some distortion. FDG-PET identified hypermetabolism in the cerebellar lesion. After establishing the diagnosis of LDD, the authors performed subtotal resection of the lesion based on the likelihood of a causal relationship between the cerebellar lesion and the vomiting center of the medulla oblongata. Postoperatively and for 2 years, VAs have remained completely suppressed. The authors hypothesize that the pathophysiology of VAs in LDD includes a tumor-like space-occupying effect on the vomiting center of the medulla oblongata, and even partial resection of the lesion may prove effective.

Cutaneous reflex modulation and self-induced reflex attenuation in cerebellar patients.

Modulation of cutaneous reflexes is important in the neural control of walking, yet knowledge about underlying neural pathways is still incomplete. Recent studies have suggested that the cerebellum is involved. Here we evaluated the possible roles of the cerebellum in cutaneous reflex modulation and in attenuation of self-induced reflexes. First we checked whether leg muscle activity during walking was similar in patients with focal cerebellar lesions and in healthy control subjects. We then recorded cutaneous reflex activity in leg muscles during walking. Additionally, we compared reflexes after standard (computer triggered) stimuli with reflexes after self-induced stimuli for both groups. Biceps femoris and gastrocnemius medialis muscle activity was increased in the patient group compared with the control subjects, suggesting a coactivation strategy to reduce instability of gait. Cutaneous reflex modulation was similar between healthy control subjects and cerebellar patients, but the latter appeared less able to attenuate reflexes to self-induced stimuli. This suggests that the cerebellum is not primarily involved in cutaneous reflex modulation but that it could act in attenuation of self-induced reflex responses. The latter role in locomotion would be consistent with the common view that the cerebellum predicts sensory consequences of movement.

Lhermitte-Duclos disease presenting with atypical positional nystagmus.

We describe a patient with dysplastic cerebellar gangliocytoma (Lhermitte-Duclos disease) who presented with an acute onset of positional disequilibrium. Video-oculography in the right Hallpike position revealed rightward torsional down-beat nystagmus, initially thought to be right anterior canal benign positional vertigo. However, the presence of spontaneous nystagmus, the persistent character of the positional nystagmus and the absence of fatigability indicated central positional nystagmus, attributable to his right-sided Lhermitte-Duclos disease. These findings emphasise the need for clinicians to reconsider a central cause before diagnosing the rare anterior canal benign positioning vertigo variant.

Cognitive characteristics of PTEN hamartoma tumor syndromes.

PURPOSE: We sought to characterize cognition in individuals with germline PTEN mutations (n = 23) as well as in PTEN mutation-negative individuals with classic Cowden syndrome or Bannayan-Riley-Ruvalcaba syndrome (n = 2). METHODS: Twenty-five individuals completed a comprehensive neuropsychological evaluation. One sample t-tests and effect sizes were used to examine differences in participant test scores compared with normal controls. Composite scores were created for each patient within each of the cognitive domains assessed and classified as above average, average, or below average according to normative standards. χ(2) analyses compared these classifications to expected proportions in normal control samples. RESULTS: The mean intelligence quotient was in the average range, and the range of intellectual functioning was very wide (from extremely low to very superior). However, in a large subset of patients, scores were lower than expected on measures of motor functioning, executive functioning, and memory recall, suggesting disruption of frontal circuits in these participants. CONCLUSION: This is the first study to characterize cognition in individuals with PTEN mutations and associated syndromes using a comprehensive neuropsychological battery. Contrary to previous reports suggesting an association with intellectual disability, the mean intelligence quotient was average, and there was a broad range of intellectual abilities. Specific evidence of disruption of frontal circuits may have implications for treatment compliance and cancer surveillance, and further investigation is warranted.

Endometrial cancer in a 14-year-old girl with Cowden syndrome: a case report.

The appearance of endometrial cancer in adolescence is uncommon and warrants investigation for an hereditary cancer syndrome. Cowden syndrome is an autosomal dominant cancer syndrome associated with a germline PTEN mutation and increased risk of breast, thyroid, endometrial and colon cancer. In this report we present a case of a 14-year-old nulligravid female diagnosed with grade 1 endometrial adenocarcinoma. She subsequently developed fibrocystic breast disease and colon polyps and was diagnosed with Cowden syndrome at age 20. We therefore recommend formal evaluation for Cowden syndrome to be considered when endometrial cancer is diagnosed in adolescence.

Lhermitte - Duclos disease with syrinx: case report and literature review.

BACKGROUND: Lhermitte-Duclos disease is typified by a hamartomatous lesion of the cerebellum. It is usually seen in females. The usual presentation is of raised intracranial pressure along with cerebellar signs. CASE REPORT: We report an 18-year-old female patient who presented to us with history of headache and gait ataxia and was observed to have Lhermitte-Duclos disease with cervical cord syrinx on imaging. DISCUSSION: To our knowledge this is the fifth case of Lhermitte-Duclos disease with syringomyelia in the pediatric age group. The treatment of this condition is decompression of the lesion. Malignant transformation never occurs and the prognosis is excellent.