Infantile Lhermitte-Duclos Disease Treated Successfully With Rapamycin

Lhermitte-Duclos disease (dysplastic cerebellar gangliocytoma) in the setting of cowden syndrome: a case report and literature review on COLD syndrome

Lhermitte-Duclos Disease is a rare clinical entity involving a dysplastic lesion of the cerebellum. The dysplastic cerebellar ganglioblastoma is often seen in association with Cowden Syndrome, an autosomal dominant disorder consisting of a mutation in the phosphatase and homologous tensin (PTEN) gene. Characteristic findings on neuroimaging allow for a pre-operative diagnosis to be made, which guides further management of the condition. This report describes the diagnosis and management of Lhermitte-Duclos Disease in a 51-year-old lady, spanning a period of almost seven years. The characteristic radiological and histological findings are presented, along with the clinical features associated with Cowden Syndrome. This patient ultimately underwent surgical intervention for symptomatic relief, which is described here.

Lhermitte-Duclos Disease in an Eight-Year-Old Boy: A Case Report

Lhermitte-Duclos disease (LDD), also known as dysplastic cerebellar gangliocytoma, is a rare, slow-growing, benign lesion that occurs in the cerebellum and is very uncommon in the pediatric population. There is a lack of literature and evidence about LDD management, and only one systematic review is available. Thus, more case reports and studies are warranted. This study reports a pediatric case diagnosed with LDD and describes the patient's clinical presentation, radiological findings, and histopathological criteria. In addition, important aspects of the disease are discussed to help reach the best management options. The main management option is surgical resection, though a "wait and see" approach is also an alternative, especially for asymptomatic patients. More studies are still needed to determine the best management options.

Lhermitte-Duclos disease: A systematic review

Background

Lhermitte-Duclos disease (LDD) is a rare tumor, with only about 300 reported cases. It often shows comorbidity with Cowden syndrome (CS); however, it can occur by itself. Radiologically, the "tiger-stripe" appearance is considered pathognomonic. Surgical resection remains the mainstay of treatment. This report aims to describe the clinical and radiological characteristics of LDD and its relationship with CS according to age group.

Methods

PubMed electronic databases were searched in August 2022. The search terms included "Lhermitte- Duclos disease" and "dysplastic gangliocytoma," which yielded 297 and 103 research articles, respectively. The articles were collected and reviewed by three researchers.

Results

Out of 400 identified articles, we analyzed 302 reported cases. The mean age at presentation was 33.6 ± 16 years; 171 patients (56.6%) were female, and 123 (40.7%) were male. The most commonly reported symptom was headache (174 patients, 57.6%), followed by ataxia (109, 36.1%). In addition, 99 cases (32.8%) were associated with CS, and 60 (19.9%) had a confirmed phosphatase and tensin homolog (PTEN) mutation. A tiger-stripe appearance was observed in 208 cases (58.7%); surgical resection was performed in 64.2% of the cases. Mortality and recurrence rates were 4.3% and 8.6%, respectively. No statistically significant difference was found between adult- and pediatric-onset LDD for the association with CS (P = 0.128).

Conclusion

Our findings suggest that adult and pediatric LDD have major commonalities; however, further prospective studies are warranted.

Rare Neuronal, Glial and Glioneuronal Tumours in Adults

Rare glial, neuronal and glioneuronal tumours in adults form a heterogeneous group of rare, primary central nervous system tumours. These tumours, with a glial and/or neuronal component, are challenging in terms of diagnosis and therapeutic management. The novel classification of primary brain tumours published by the WHO in 2021 has significantly improved the diagnostic criteria of these entities. Indeed, diagnostic criteria are nowadays multimodal, including histological, immunohistochemical and molecular (i.e., genetic and methylomic). These integrated parameters have allowed the specification of already known tumours but also the identification of novel tumours for a better diagnosis.

Dysplastic gangliocytoma of the cerebellum in a cat

A 2.5-year-old cat presented with progressive ataxia and lethargy. Magnetic resonance imaging (MRI) showed enlargement of the cerebellum and herniation of cerebellar vermis. Postmortem examination confirmed the MRI findings, and histopathology showed numerous large dysplastic neurons populating and displacing the Purkinje cell layer and extending into the molecular and granular layers of the cerebellum. The lesion was diagnosed as dysplastic gangliocytoma of the cerebellum. In humans, this tumor is often associated with Cowden syndrome, a genetic disorder characterized by multiple hamartomas and an increased risk of developing certain neoplasms, known to be linked to a germline mutation of the phosphatase and tensin homolog (PTEN) gene. Reduction in PTEN nuclear and cytoplasmic immunohistochemical labeling of dysplastic neurons in this case suggested a possible PTEN mutation involved in the tumorigenesis. This report provides a detailed pathology description of the tumor and the use of neuronal and PTEN markers which will help guide pathologists presented with this rare condition in the future.

MR imaging features of Lhermitte-Duclos disease: Case reports and literature review

RATIONALE

Lhermitte-Duclos disease (LDD) is a rare tumor of the nervous system with a typical "tiger striped'" sign, but its features on functional magnetic resonance imaging (fMRI) are still inconclusive.

PATIENT CONCERNS

To explore the characteristics of LDDs using fMRI.

DIAGNOSES

We report 3 cases of pathologically confirmed LDDs.

INTERVENTIONS

Three patients underwent brain tumor surgery.

OUTCOMES

All the patients had a good prognosis.

LESSONS

Magnetic resonance spectroscopy and susceptibility-weighted imaging combined with conventional MRI can be used to better diagnose LDDs. Perfusion-weighted imaging is not specific for distinguishing cerebellar tumors. The combined application of fMRI and conventional MRI can improve the accuracy of LDD diagnoses.

Regulating tumor suppressor genes: post-translational modifications

Tumor suppressor genes cooperate with each other in tumors. Three important tumor suppressor proteins, retinoblastoma (Rb), p53, phosphatase, and tensin homolog deleted on chromosome ten (PTEN) are functionally associated and they regulated by post-translational modification (PTMs) as well. PTMs include phosphorylation, SUMOylation, acetylation, and other novel modifications becoming growing appreciated. Because most of PTMs are reversible, normal cells use them as a switch to control the state of cells being the resting or proliferating, and PTMs also involve in cell survival and cell cycle, which may lead to abnormal proliferation and tumorigenesis. Although a lot of studies focus on the importance of each kind of PTM, further discoveries shows that tumor suppressor genes (TSGs) form a complex "network" by the interaction of modification. Recently, there are several promising strategies for TSGs for they change more frequently than carcinogenic genes in cancers. We here review the necessity, characteristics, and mechanisms of each kind of post-translational modification on Rb, p53, PTEN, and its influence on the precise and selective function. We also discuss the current antitumoral therapies of Rb, p53 and PTEN as predictive, prognostic, and therapeutic target in cancer.

PTEN in Hereditary and Sporadic Cancer

Germline pathogenic phosphatase and tensin homolog (PTEN) mutations cause PTEN hamartoma tumor syndrome (PHTS), characterized by various benign and malignant tumors of the thyroid, breast, endometrium, and other organs. Patients with PHTS may present with other clinical features such as macrocephaly, intestinal polyposis, cognitive changes, and pathognomonic skin changes. Clinically, deregulation of PTEN function is implicated in other human diseases in addition to many types of human cancer. PTEN is an important phosphatase that counteracts one of the most critical cancer pathways: the phosphatidylinositol 3-kinase (PI3K)/AKT signaling pathways. Although PTEN can dephosphorylate lipids and proteins, it also has functions independent of phosphatase activity in normal and pathological states. It is positively and negatively regulated at the transcriptional level as well as posttranslationally by phosphorylation, ubiquitylation, oxidation, and acetylation. Although most of its tumor-suppressor activity is likely to be caused by lipid dephosphorylation at the plasma membrane, PTEN also resides in the cytoplasm and nucleus, and its subcellular distribution is under strict control. In this review, we highlight our current knowledge of PTEN function and recent discoveries in understanding PTEN function regulation and how this can be exploited therapeutically for cancer treatment.

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.

PI3K isoforms in cell signalling and vesicle trafficking

PI3Ks are a family of lipid kinases that phosphorylate intracellular inositol lipids to regulate signalling and intracellular vesicular traffic. Mammals have eight isoforms of PI3K, divided into three classes. The class I PI3Ks generate 3-phosphoinositide lipids, which directly activate signal transduction pathways. In addition to being frequently genetically activated in cancer, similar mutations in class I PI3Ks have now also been found in a human non-malignant overgrowth syndrome and a primary immune disorder that predisposes to lymphoma. The class II and class III PI3Ks are regulators of membrane traffic along the endocytic route, in endosomal recycling and autophagy, with an often indirect effect on cell signalling. Here, we summarize current knowledge of the different PI3K classes and isoforms, focusing on recently uncovered biological functions and the mechanisms by which these kinases are activated. Deeper insight into the PI3K isoforms will undoubtedly continue to contribute to a better understanding of fundamental cell biological processes and, ultimately, of human disease.

Successful Treatment of Juvenile Polyposis of Infancy With Sirolimus

Juvenile polyposis syndrome is a rare autosomal dominant condition characterized by multiple hamartomatous polyps throughout the gastrointestinal tract. Juvenile polyposis of infancy is a generalized severe form of juvenile polyposis syndrome associated with a poor prognosis. A 47-month-old female infant presented initially with gastrointestinal bleeding and protein-losing enteropathy at 4 months of age. At the age of 12 months, the condition worsened, requiring albumin infusions every 24 to 48 hours and red blood cell transfusions every 15 days. Upper gastrointestinal endoscopy, colonoscopy, and small-bowel enteroscopy revealed diffuse polyposis that was treated with multiple endoscopic polypectomies. Despite subtotal colectomy with ileorectal anastomosis, protein-losing enteropathy and bleeding persisted, requiring continued blood transfusions and albumin infusions. A chromosomal microarray revealed a single allele deletion in chromosome 10q23, involving both the PTEN and BMPR1A genes. Loss of PTEN function is associated with an increased activation of the protein kinase B (AKT)/mammalian target of rapamycin (mTOR) pathway involved in cell proliferation. Treatment with sirolimus, an mTOR inhibitor, was initiated with the aim of inhibiting polyp growth. Soon after initiation of treatment with sirolimus, blood and albumin infusions were no longer needed and resulted in improved patient growth and quality of life. This case represents the first detailed report of successful drug therapy for life-threatening juvenile polyposis of infancy.

Everolimus as adjunctive therapy for tuberous sclerosis complex-associated partial-onset seizures

Introduction: Tuberous sclerosis complex (TSC) is a rare genetic disorder resulting in benign tumors in various organs. It is caused by mutations in TSC1 or TSC2 genes causing hyperactivation of the mammalian target of rapamycin (mTOR) pathway. The majority of patients with TSC develop epilepsy, and approximately two-thirds become refractory to antiepileptic drugs (AEDs). Recently, the mTOR inhibitor everolimus was approved as adjunctive therapy for TSC-associated partial seizures. Areas covered: This article covers different characteristics of everolimus, including major clinical trials leading to its approval in TSC-associated partial seizures, safety concerns, drug pharmacokinetics/pharmacodynamics, and an overview of potential competitors and other agents used to treat TSC-associated seizures. Expert opinion: Unlike many other therapies for treating TSC-associated seizures, everolimus addresses the underlying pathophysiology of TSC, and since it has also been shown to improve other TSC manifestations such as subependymal giant cell astrocytomas and renal angiomyolipomas, everolimus provides a potential multisystemic therapy for TSC. An important avenue for future research is exploring the possible use of everolimus as a preventative treatment for seizures as there is the potential to prevent negative developmental outcomes associated with TSC.

PTEN-opathies: from biological insights to evidence-based precision medicine

The tumor suppressor phosphatase and tensin homolog (PTEN) classically counteracts the PI3K/AKT/mTOR signaling cascade. Germline pathogenic PTEN mutations cause PTEN hamartoma tumor syndrome (PHTS), featuring various benign and malignant tumors, as well as neurodevelopmental disorders such as autism spectrum disorder. Germline and somatic mosaic mutations in genes encoding components of the PI3K/AKT/mTOR pathway downstream of PTEN predispose to syndromes with partially overlapping clinical features, termed the "PTEN-opathies." Experimental models of PTEN pathway disruption uncover the molecular and cellular processes influencing clinical phenotypic manifestations. Such insights not only teach us about biological mechanisms in states of health and disease, but also enable more accurate gene-informed cancer risk assessment, medical management, and targeted therapeutics. Hence, the PTEN-opathies serve as a prototype for bedside to bench, and back to the bedside, practice of evidence-based precision medicine.

Clinical spectrum of PTEN mutation in pediatric patients. A bicenter experience

OBJECTIVE OF THE STUDY

To give a full overview of the clinical presentation of PTEN mutations in pediatric patients and to propose a pediatric follow-up protocol.

METHODS

Recruitment of 16 PTEN mutated children (age 6 months-11 years) from two pediatric centers in Milan (Italy) between 2006 and 2017. All the patients underwent clinical and neurologic evaluations, cognitive and behavioral tests, and brain MRI; they are currently following an oncologic follow-up.

RESULTS

Extreme macrocephaly is present in all the patients (69% HC above +4 SD). Neuropsychiatric issues have high prevalence, with 56% of patients showing developmental delay and 25% showing autism spectrum disorder. Brain MRI reveals in 75% of the patients at least one of the following: enlarged perivascular spaces, white matter anomalies, and/or downward displacement of the cerebellar tonsils through the foramen magnum, resulting in Chiari I malformation in two patients. Vascular malformations have a prevalence of 19%, with further evidence that complex cardiovascular malformations may be related to PTEN mutations; 31% of patients present hamartomas. None of our patients have so far experienced any oncologic complication.

CONCLUSIONS

We suggest to screen for PTEN mutations all children presenting macrocephaly and one of the following: neurodevelopmental issues, one of the three major brain MRI anomalies, cutaneous lesions, vascular malformations, family history positive for PTEN related malignancies; or also with macrocephaly alone when exceeding +3 SD. Basing on our cohort results and further recent studies on the condition, we recommend a follow-up protocol that includes annual clinical and dermatological examination, thyroid and abdominal US, and Fecal Occult Blood test plus neurodevelopmental evaluation, heart US (to exclude congenital heart malformations), and brain MRI (to exclude Chiari I malformation) at diagnosis.

65 YEARS OF THE DOUBLE HELIX: One gene, many endocrine and metabolic syndromes: PTEN-opathies and precision medicine

An average of 10% of all cancers (range 1-40%) are caused by heritable mutations and over the years have become powerful models for precision medicine practice. Furthermore, such cancer predisposition genes for seemingly rare syndromes have turned out to help explain mechanisms of sporadic carcinogenesis and often inform normal development. The tumor suppressor PTEN encodes a ubiquitously expressed phosphatase that counteracts the PI3K/AKT/mTOR cascade - one of the most critical growth-promoting signaling pathways. Clinically, individuals with germline PTEN mutations have diverse phenotypes and fall under the umbrella term PTEN hamartoma tumor syndrome (PHTS). PHTS encompasses four clinically distinct allelic overgrowth syndromes, namely Cowden, Bannayan-Riley-Ruvalcaba, Proteus and Proteus-like syndromes. Relatedly, mutations in other genes encoding components of the PI3K/AKT/mTOR pathway downstream of PTEN also predispose patients to partially overlapping clinical manifestations, with similar effects as PTEN malfunction. We refer to these syndromes as 'PTEN-opathies.' As a tumor suppressor and key regulator of normal development, PTEN dysfunction can cause a spectrum of phenotypes including benign overgrowths, malignancies, metabolic and neurodevelopmental disorders. Relevant to clinical practice, the identification of PTEN mutations in patients not only establishes a PHTS molecular diagnosis, but also informs on more accurate cancer risk assessment and medical management of those patients and affected family members. Importantly, timely diagnosis is key, as early recognition allows for preventative measures such as high-risk screening and surveillance even prior to cancer onset. This review highlights the translational impact that the discovery of PTEN has had on the diagnosis, management and treatment of PHTS.

Lhermitte-Duclos Disease in a Six-Year Old Child: A Rare Presentation

Lhermitte-Duclos disease (LDD) is a rare, slow-growing, benign lesion of the cerebellum. It is often seen in the second and fourth decades. This disease is extremely rare in childhood. A 6-year-old girl presented with loss of balance. A mass lesion in the right cerebellum was detected by magnetic resonance imaging. The patient underwent surgical removal of the lesion, and the histological diagnosis was dysplastic gangliocytoma (LDD). The patient was discharged without complication, and her balance improved in the follow-up period. In this report, we present this rare occurrence in childhood and discuss the clinical course and management. LDD is very rare in early childhood and should be considered in the differential diagnosis of posterior fossa lesions.