PTEN hamartoma tumor syndrome in childhood and adolescence-a comprehensive review and presentation of the German pediatric guideline

Cancer and Overgrowth Manifestations of PTEN Hamartoma Tumor Syndrome: Management Recommendations from the International PHTS Consensus Guidelines Working Group

PURPOSE

PTEN hamartoma tumor syndrome (PHTS) is an autosomal dominant cancer predisposition and overgrowth syndrome caused by pathogenic germline variants in the PTEN gene, with an increased risk of both benign and malignant tumors involving the breast, colon, endometrium, thyroid, skin, and kidney. The objective of these clinical guidelines was to use the latest knowledge to generate an international consensus resource for providers, researchers, and individuals with PHTS on the best practices in the surveillance and management of cancer and overgrowth in PHTS.

EXPERIMENTAL DESIGN

The International PHTS Cancer and Overgrowth Guidelines Working Group was established, comprising a core group of six international experts in the diagnosis and management of PHTS. The working group held joint meetings with individuals with PHTS and their advocates. Informed by the literature, the working group met regularly between 2022 and 2024 to produce guideline statements, refined through iterative feedback. A modified Delphi approach was used with an independent external panel of PHTS, genetics, and cancer experts to establish final consensus guidelines.

RESULTS

Clinical consensus recommendations for the surveillance and management of cancer and overgrowth in individuals with PHTS were formed. The guidelines encompass the recommended practices in cases of breast, colon, endometrial, thyroid, and kidney cancers, as well as overgrowths.

CONCLUSIONS

The clinical management of individuals with PHTS is complex and necessitates a multidisciplinary approach. We generated international consensus guidelines for the surveillance and management of cancer and overgrowth in PHTS, aiming at improving care for affected individuals and families.

Experience in a PTEN Hamartoma Tumor Syndrome Expertise Centre: Yield of Thyroid Ultrasound Surveillance in Children with PTEN Hamartoma Tumor Syndrome

Objective

Children with PTEN hamartoma tumor syndrome (PHTS) are at increased risk for developing thyroid abnormalities, including differentiated thyroid carcinoma (DTC). The Dutch PHTS guideline recommends ultrasound surveillance starting from age 18 years. Since the literature describes PHTS patients who developed DTC before this age, the Dutch PHTS expertise center has initiated annual ultrasound surveillance starting from age 12 years. The purpose of this study was to identify the yield of thyroid ultrasound surveillance using this cut-off.

Methods

A retrospective, single center, cohort study was conducted. Pediatric PHTS patients who received thyroid ultrasound surveillance before age 18 years between 2016-2023 were included. Medical records were reviewed. Primary outcomes included prevalence and time to develop thyroid nodules ≥10 mm, nodular growth, goiter, thyroiditis and DTC. Descriptive statistics and Kaplan-Meier analyses were performed.

Results

Forty-three patients were included. Two (5%) were diagnosed with DTC at ages 12 and 17 years. Both DTCs were identified as minimally invasive follicular carcinoma at stages pT3NxMx and pT1NxMx respectively. A total of 84% were diagnosed with thyroid abnormalities at a median age of 12 (9-18) years. Most common findings were benign, including nodular disease (74%), goiter (30%) and autoimmune thyroiditis (12%). Nodular growth was observed in 14 patients (33%) resulting in (hemi)thyroidectomy in 7 (16%).

Conclusion

Thyroid ultrasound surveillance resulted in the detection of DTC in 2/43 (4.65%) PHTS patients before age 18. These findings support the recommendation to initiate thyroid ultrasound surveillance in children with PHTS from at least age 12, preferably within an expertise center.

Atypical thyroid manifestation in Cowden disease: a case report and literature review

Background

Cowden syndrome (CS) is a complex and rare hereditary disorder characterized by a high risk of developing both benign and malignant tumors. Germline variants in the PTEN gene lead to this autosomal dominant syndrome, which predisposes individuals to lesions of the skin and mucous membranes, as well as breast, thyroid, endometrial, and kidney cancers. Early identification of symptoms is essential for implementing effective therapeutic strategies, especially in managing thyroid cancer risk.

Case presentation

During a tonsillectomy in an 8-year-old boy, the surgeon incidentally noted a left lateralized thyroid swelling. The clinical picture of Cowden syndrome was further supported by the presence of macrocephaly and intellectual disability since birth along with rare and atypical thyroid disorder marked by a toxic adenoma. Genetic analysis of both the tissue and blood samples confirmed the diagnosis. The clinical manifestation of thyroid issues in a young child may indicate CS, a condition that is often poorly assessed by clinicians. Family history revealed that the boy's father and sister also carry the same heterozygous variant, presenting a spectrum of Cowden syndrome manifestations.

Conclusion

Molecular analysis of the PTEN gene should be considered in young patients with thyroid nodules or nodules associated with abnormal thyroid function test, even without clear evidence of Cowden syndrome, particularly if there is a family history of thyroid, breast, or hamartoma-related conditions.

Phenotypic rescue via mTOR inhibition in neuron-specific Pten knockout mice reveals AKT and mTORC1-site specific changes

Phosphatase and Tensin Homolog (PTEN) is a dual-specific protein and lipid phosphatase that regulates AKT and downstream signaling of the mechanistic target of rapamycin (mTOR). PTEN functions as a tumor suppressor gene whose mutations result in PTEN Hamartoma Tumor Syndrome (PHTS) characterized by increased cancer risk and neurodevelopmental comorbidity. Here, we generated a novel neuron-specific Pten knock-out mouse model (Syn-Cre/Pten HOM) to test the ability of pharmacologic mTOR inhibition to rescue Pten mutation-associated disease phenotypes in vivo and in vitro. We found that treatment with the mTOR inhibitor, everolimus, increased the survival of Syn-Cre/Pten HOM mice while some neurologic phenotypes persisted. Transcriptomic analyses revealed that in contrast to mice harboring a neuron-specific deletion of the Tuberous Sclerosis Complex 2 gene (Syn-Cre/Tsc2 KO), genes that are under AKT regulation were significantly increased in the Syn-Cre/Pten HOM mice. In addition, genes associated with synapse, extracellular matrix, and myelination were broadly increased in Syn-Cre/Pten HOM mouse neocortex. These findings were confirmed by immunostaining of cortical sections in vivo, which revealed excessive immunoreactivity of myelin basic protein and perineuronal nets (PNN), the specialized extracellular matrix surrounding fast-spiking parvalbumin (PV) interneurons. We also detected increased expression of Synapsin I/PSD95 positive synapses and network hyperactivity phenotypes in Syn-Cre/Pten HOM mice neurons compared to wild-type (WT) neurons in vitro. Strikingly, everolimus treatment rescued the number of synapses and network hyperactivity in the Syn-Cre/Pten HOM mice cortical neuron cultures. Taken together, our results revealed in vivo and in vitro molecular and neuronal network mechanisms underlying neurological phenotypes of PHTS. Notably, pharmacologic mTOR inhibition by everolimus led to successful downstream signaling rescue, including mTOR complex 1 (mTORC1) site-specific suppression of S6 phosphorylation, correlating with phenotypic rescue found in our novel neuron-specific Syn-Cre/Pten HOM mice.

Non-malignant features of cancer predisposition syndromes manifesting in childhood and adolescence: a guide for the general pediatrician

PURPOSE

Cancer predisposition syndromes are genetic disorders that significantly raise the risk of developing malignancies. Although the malignant manifestations of cancer predisposition syndromes are well-studied, recognizing their non-malignant features is crucial for early diagnosis, especially in children and adolescents.

METHODS

A comprehensive literature search was conducted using the PubMed database, focusing on non-malignant manifestations of cancer predisposition syndromes in children and adolescents. Key sources included the Clinical Cancer Research pediatric oncology series and ORPHANET. Studies that described clinical signs and symptoms affecting specific organ systems were included.

RESULTS

Non-malignant dermatological features often serve as early indicators of cancer predisposition syndromes, including café-au-lait spots in Neurofibromatosis Type 1 and facial angiofibromas in Tuberous Sclerosis Complex. Neurological and developmental anomalies such as cerebellar ataxia in ataxia-telangiectasia and intellectual disabilities in neurofibromatosis type 1 and tuberous sclerosis complex are significant indicators. Growth and metabolic anomalies are also notable, including overgrowth in Beckwith-Wiedemann syndrome and growth hormone deficiency in neurofibromatosis Type 1. In addition, facial anomalies, ocular manifestations, hearing issues, and thyroid anomalies are prevalent across various cancer predisposition syndromes. For instance, hearing loss may be significant in neurofibromatosis Type 2, while thyroid nodules are common in PTEN hamartoma tumor syndrome and DICER1 syndrome. Cardiovascular, abdominal, musculoskeletal, pulmonary, genitourinary manifestations, and prenatal deviations further complicate the clinical picture.

CONCLUSIONS

Recognizing non-malignant features of cancer predisposition syndromes is essential for early diagnosis and management. This organ-specific overview furthers awareness among healthcare providers, facilitating timely genetic counseling, surveillance programs, and preventive measures, ultimately improving patient outcomes.

Piloting an automated query and scoring system to facilitate APDS patient identification from health systems

Introduction

Patients with activated PI3Kδ syndrome (APDS) may elude diagnoses for nearly a decade. Methods to hasten the identification of these patients, and other patients with inborn errors of immunity (IEIs), are needed. We sought to demonstrate that querying electronic health record (EHR) systems by aggregating disparate signs into a risk score can identify these patients.

Methods

We developed a structured query language (SQL) script using literature-validated APDS-associated clinical concepts mapped to ICD-10-CM codes. We ran the query across EHRs from 7 large, US-based medical centers encompassing approximately 17 million patients. The query calculated an "APDS Score," which stratified risk for APDS for all individuals in these systems. Scores for all known patients with APDS (n=46) were compared.

Results

The query identified all but one known patient with APDS (98%; 45/46) as well as patients with other complex disease. Median score for all patients with APDS was 9 (IQR = 5.75; range 1-25). Sensitivity analysis suggested an optimal cutoff score of 7 (sensitivity = 0.70).

Conclusion

Disease-specific queries are a relatively simple method to foster patient identification across the rare-disease spectrum. Such methods are even more important for disorders such as APDS where an approved, pathway-specific treatment is available in the US.

A Newborn with Cleft Palate Associated with PTEN Hamartoma Tumor Syndrome

Background: PTEN hamartoma tumor syndrome (PHTS) has evolved into an umbrella term for a range of syndromes, characterized by loss-of-function variants in the phosphatase and tensin homolog (PTEN) tumor suppressor gene on chromosome 10q23.31. This can result in a lifelong tumor predisposition in patients. Often, the syndrome is diagnosed in early childhood because of macrocephaly, dermatological findings, or development delay. Since the correlation between phenotype and genotype is weak, and the penetrance is age-dependent, this poses the question of the appropriate timing of potentially invasive and burdensome examinations for early cancer detection. Case: The present report describes an infant with cleft palate associated with PHTS, a rare occurrence, though the initial report of Cowden syndrome already pointed to oromaxillofacial abnormalities. The recent pediatric literature is reviewed to assess which clinical symptoms should raise suspicion of PHTS and may then lead to early genetic counseling. Conclusion: Since the amount of prospective data remains limited, and the estimation of tumor risk during infancy and adulthood is very difficult, we advocate for early and broad genetic testing in suspected cases, to gain more insights into this rare disease and allow for better counseling for patients and their families.

[Thyroid cancer in a child with Cowden syndrome]

Cowden disease (Cowden syndrome) refers to PTEN-associated hamartoma tumor syndromes. It arises due to a mutation in the phosphatase and tensin homolog gene, one of the main functions of which is cell cycle regulation. The presence of a mutation in the gene leads to uncontrolled cell growth, and patients have a lifelong increased risk of neoplasms of various degrees of malignancy. This article presents a clinical case of Cowden syndrome with an early debut at the age of 7 years. The combination of macrocephaly (SDS of head circumference >2) with various skin manifestations (facial trichilemmomas, acral keratosis, papillomatous papules) and the presence of benign and/or malignant neoplasms are pathognomonic for Cowden syndrome. Of the malignancies, breast and thyroid cancer, colorectal cancer, renal cell carcinoma, and endometrial cancer are the most common. Thyroid carcinoma has been shown to have an earlier age of manifestation and often occurs already in childhood. This determines the need to screen patients with a proven mutation in the PTEN gene for nodal neoplasms from an early age. If surgical treatment is necessary, thyroidectomy remains preferable due to the frequent recurrence of nodules, as well as the uncertain potential for malignancy due to the low study of thyroid nodules in patients with mutations in the PTEN gene.

Clinical Neurologic Features and Evaluation of PTEN Hamartoma Tumor Syndrome: A Systematic Review

BACKGROUND AND OBJECTIVES

PTEN hamartoma tumor syndrome (PHTS) is a well-recognized hereditary tumor syndrome and is now also recognized as a common cause of monogenic autism spectrum disorder. There is a vast spectrum of phenotypic variability across individuals with PHTS, and in addition to neurodevelopmental challenges, patients with PHTS may experience a wide variety of neurologic challenges, many of which have only recently been described. Thus, this systematic review aimed to summarize the breadth of the current knowledge of neurologic conditions in individuals with PHTS.

METHODS

We conducted a systematic review using the MEDLINE and EMBASE databases until January 2023. We included studies that reported neurologic signs, symptoms, and diagnoses in patients with a diagnosis of PHTS. Two independent reviewers extracted data (neurologic diagnoses and patient details) from each study. Case reports, case series, prospective studies, and therapeutic trials were included. We assessed the quality of evidence using the appropriate tool from the JBI, depending on study design.

RESULTS

One thousand nine hundred ninety-six articles were screened, and 90 articles met the inclusion criteria. The majority of the included studies were case reports (49/90, 54%) or small case series (31/90, 34%). Epilepsy secondary to cerebral malformations, neurologic deficits from spinal or cranial arteriovenous malformations, and rare tumors such as dysplastic cerebellar gangliocytoma are among the more severe neurologic features reported across patients with PHTS. One interventional randomized control trial examining neurocognitive endpoints was identified and did not meet its efficacy endpoint.

DISCUSSION

Our systematic review defines a broad scope of neurologic comorbidities occurring in individuals with PHTS. Neurologic findings can be categorized by age at onset in individuals with PTHS. Our study highlights the need for additional clinical trial endpoints, informed by the neurologic challenges faced by individuals with PHTS.

A systematic review of Bannayan - Riley - Ruvalcaba syndrome

Bannayan-Riley-Ruvalcaba syndrome (BRRS) is a rare overgrowth condition caused by a pathogenic variant in the phosphatase and tensin homolog (PTEN) gene and belongs to a group of disorders called PTEN hamartoma tumor syndrome (PHTS). The diagnosis is often complicated by great phenotypic diversity. Furthermore, to this date treatment options are limited. Here we performed a systematic review using PubMed, Cochrane, and Scopus databases to identify cases of pediatric patients diagnosed with BRRS and summarized information about the clinical presentation, treatment, and long-term patient care. A total of 83 pediatric patients with BRRS were identified. The most common clinical findings were macrocephaly (77%) and developmental disorders (63%). Surgical interventions were the treatment of choice, described in 19 articles. Patient surveillance was proposed in 15 case reports and mostly aimed at periodic cancer screening. Recognition of BRRS clinical symptoms and early referral to a geneticist is important for better disease control and overall prognosis. As targeted treatment is still lacking, symptom relief and long-term surveillance remain the main management strategies.

Do metabolic deficits contribute to sleep disruption in monogenic intellectual disability syndromes?

Intellectual disability is defined as limitations in cognitive and adaptive behavior that often arise during development. Disordered sleep is common in intellectual disability and, given the importance of sleep for cognitive function, it may contribute to other behavioral phenotypes. Animal models of intellectual disability, in particular of monogenic intellectual disability syndromes (MIDS), recapitulate many disease phenotypes and have been invaluable for linking some of these phenotypes to specific molecular pathways. An emerging feature of MIDS, in both animal models and humans, is the prevalence of metabolic abnormalities, which could be relevant for behavior. Focusing on specific MIDS that have been molecularly characterized, we review sleep, circadian, and metabolic phenotypes in animal models and humans and propose that altered metabolic state contributes to the abnormal sleep/circadian phenotypes in MIDS.

Cancer predisposing syndromes in childhood and adolescence pose several challenges necessitating interdisciplinary care in dedicated programs

Introduction

Genetic disposition is a major etiologic factor in childhood cancer. More than 100 cancer predisposing syndromes (CPS) are known. Surveillance protocols seek to mitigate morbidity and mortality. To implement recommendations in patient care and to ascertain that the constant gain of knowledge forces its way into practice specific pediatric CPS programs were established.

Patients and methods

We retrospectively analyzed data on children, adolescents, and young adults referred to our pediatric CPS program between October 1, 2021, and March 31, 2023. Follow-up ended on December 31, 2023.

Results

We identified 67 patients (30 male, 36 female, 1 non-binary, median age 9.5 years). Thirty-five patients were referred for CPS surveillance, 32 for features suspicious of a CPS including café-au-lait macules (n = 10), overgrowth (n = 9), other specific symptoms (n = 4), cancer suspicious of a CPS (n = 6), and rare neoplasms (n = 3). CPS was confirmed by clinical criteria in 6 patients and genetic testing in 7 (of 13). In addition, 6 clinically unaffected at-risk relatives were identified carrying a cancer predisposing pathogenic variant. A total of 48 patients were eventually diagnosed with CPS, surveillance recommendations were on record for 45. Of those, 8 patients did not keep their appointments for various reasons. Surveillance revealed neoplasms (n = 2) and metachronous tumors (n = 4) by clinical (n = 2), radiological examination (n = 2), and endoscopy (n = 2). Psychosocial counselling was utilized by 16 (of 45; 35.6%) families.

Conclusions

The diverse pediatric CPSs pose several challenges necessitating interdisciplinary care in specified CPS programs. To ultimately improve outcome including psychosocial well-being joint clinical and research efforts are necessary.

Imaging findings of children with PTEN-related hamartoma tumor syndrome: a 20-year multicentric pediatric cohort

BACKGROUND

PTEN-related hamartoma tumor syndrome results from a mutation in the PTEN gene located at 10q23.31. This syndrome represents a spectrum of different phenotypes of variable expressions, now recognized as part of the same condition. Patients with this mutation have an increased risk of developing a wide range of findings, including malignancies. Although widely described in adults, there are no large series describing the imaging findings in patients before adulthood. Knowledge of the findings seen in children and adolescents with PTEN-related hamartoma tumor syndrome can help guide further management and improve surveillance recommendations.

OBJECTIVE

To describe the spectrum of imaging abnormalities in pediatric patients with PTEN-related hamartoma tumor syndrome.

MATERIALS AND METHODS

We performed a retrospective, cross-sectional, multicenter study conducted between January 2000 and October 2021 in three tertiary pediatric institutions evaluating the imaging findings in children and adolescents (≤ 18 years) with confirmed diagnoses of a PTEN mutation. For each patient, the imaging findings, histopathology reports, and at least a 2-year follow-up of clinical outcomes for non-operative cases were documented.

RESULTS

The cohort included 78 children (37 girls), with a mean age at diagnosis of 7.5 years (range 0 days to 18 years). Benign brain findings included enlarged Virchow-Robin perivascular spaces, white matter changes, developmental venous anomalies, and cerebellar hamartomas. Benign thyroid findings were common, but 5/45 (11.1%) with thyroid abnormalities had a malignant nodule. Soft tissue adipocytic tumors, GI/GU polyps, other soft tissue abnormalities, along with vascular anomalies in various anatomic locations were common.

CONCLUSION

Brain abnormalities, benign non-vascular soft tissue abnormalities, and vascular anomalies are commonly seen in children and adolescents with PTEN-related hamartoma tumor syndrome. However, malignancies involving the thyroid gland are not uncommon. Familiarity with the phenotype of PTEN-related hamartoma tumor syndrome in the pediatric population can improve diagnosis and prompt appropriate clinical surveillance of abnormal findings that warrant further management.

Case report: Association between PTEN-gene variant and an aggressive case of multiple dAVFs

Introduction

Mutations of the phosphatase and tensin homolog (PTEN) gene have been associated with a spectrum of disorders called PTEN hamartoma tumor syndrome, which predisposes the individual to develop various types of tumors and vascular anomalies. Its phenotypic spectrum includes Cowden syndrome (CS), Bannayan-Riley-Ruvalcaba syndrome (BRRS), Proteus syndrome, autism spectrum disorders (ASD), some sporadic cancers, Lhermitte-Duclos disease (LDD), and various types of associated vascular anomalies.

Clinical presentation

A previously healthy 27-year-old woman was experiencing visual scintillating scotomas and mild chronic headaches for the past 2 years. The initial computed tomographic (CT) and magnetic resonance imaging (MRI) scans did not reveal any abnormalities, but the possibility of pseudotumor cerebri was considered. Furthermore, a cerebral angiogram showed a posterior fossa dural arteriovenous fistula (dAVF), which was initially treated through embolization. However, in spite of proper treatment, this patient experienced multiple recurrent dAVFs in different locations, requiring multiple embolizations and surgeries. Despite exhibiting altered cerebral perfusion and hemodynamics, the patient did not display any significant symptoms until she experienced a sudden stroke resulting from deep venous thrombosis, which was not associated with any medical procedures or medication use. A comprehensive analysis was performed due to the aggressive nature of the dAVFs. Surprisingly, exome sequencing of a blood sample revealed a PTEN gene variant in chromosome 10, indicative of Cowden syndrome. However, no tumors or other vascular lesions were detected in other systems that would constitute Cowden syndrome.

Conclusion

The rapid formation of multiple and complex dAVFs, coupled with not meeting the criteria for any other PTEN-related syndrome, unequivocally leads to the presentation of a novel phenotype of the PTEN germline variant.

The complexity of phosphatase and tensin homolog hamartoma tumor syndrome: A case report

Germline pathogenic variants found in the phosphatase and tensin homolog gene are associated with a range of rare syndromes that collectively fall under the umbrella of phosphatase and tensin homolog hamartoma tumor syndromes. Due to the wide array of possible clinical presentations and the varying degrees of symptom severity, many individuals with phosphatase and tensin homolog hamartoma tumor syndromes might remain undiagnosed for an extended period. We describe a case of a male child who received the diagnosis at the age of 12. His clinical features included macrocephaly, hypertrophy in the left arm, thyroid nodules, penile freckles, developmental delay, and an autism spectrum disorder. Whole exome sequencing revealed a de novo heterozygous variant in the phosphatase and tensin homolog. The case highlights the diverse and complex nature of phosphatase and tensin homolog hamartoma tumor syndromes, emphasizing the necessity for early diagnosis, multidisciplinary care, and surveillance protocols, offering the potential for improved prognostic outcomes and enhanced quality of life for affected individuals.

Differential Diagnoses and Management Approaches for Gastric Polyposis

Multiple gastric polyps are observed in various polyposis syndromes and conditions associated with polypoid lesion development in the stomach. Polyposis syndromes often occur concurrently with specific malignant tumors and can manifest at any point in an individual’s lifespan, thus explaining the diversity in surveillance methods. Furthermore, genetic counseling and surveillance are essential not only for the patients themselves but also for their blood relatives. Therefore, the accurate diagnosis and appropriate surveillance of multiple gastric polyps are crucial for improving patient outcomes. This review aims to provide essential information on such lesions along with representative endoscopic images of familial adenomatous polyposis, Peutz-Jeghers syndrome, Cowden syndrome, Cronkhite-Canada syndrome, juvenile polyposis syndrome, gastric adenocarcinoma and proximal polyposis of the stomach, neuroendocrine tumors in autoimmune gastritis, proton pump inhibitor-related gastric mucosal changes, and multiple submucosal heterotopic glands. We wish for this review to serve as a valuable resource for endoscopists seeking to deepen their comprehension of gastric polyposis.

Case Report - Multinodular goiter in a patient with Congenital Hypothyroidism and Bannayan-Riley-Ruvalcaba syndrome: the possible synergic role of TPO and PTEN mutation

We report the case of a paediatric female patient affected by Bannayan-Riley-Ruvalcaba syndrome (BRRS) and congenital hypothyroidism (CH) with homozygous mutation of the TPO gene. She underwent total thyroidectomy at the age of seven years because of the development of a multinodular goiter. BRRS patients present an increased risk of benign and malignant thyroid disease since childhood because of inactivating mutation of PTEN, an onco-suppressor gene. Instead, homozygous mutations in the TPO gene can be associated with severe forms of hypothyroidism with goiter; previous studies have described cases of follicular and papillary thyroid cancer in CH patients with TPO mutation despite a perfectly controlled thyroid function with Levothyroxine therapy. To our knowledge, this is the first case that describes the possible synergic role of coexisting mutation of both TPO and PTEN in the development of multinodular goiter underlining the importance of a tailored surveillance program in these patients, especially during childhood.

Characteristics of PTEN Mutation in Thyroid Tumours: A Retrospective Chart Review

While some studies suggest that PTEN mutations correlate with a low-risk phenotype in pediatric thyroid nodules, the relationship between the mutation and malignancy in the adult populations is abstruse. This study investigated whether PTEN mutations result in thyroid malignancy, and whether these malignancies are aggressive. This multicenter study involved 316 patients who underwent preoperative molecular testing, and subsequent lobectomy or total thyroidectomy at two quaternary care hospitals. A four-year retrospective review was performed on the 16 charts of patients that opted for surgery following a positive PTEN mutation on molecular testing results from January 2018 to December 2021. Of the total 16 patients, 37.5% (n = 6) had malignant tumours, 18.75% (n = 3) had non-invasive follicular thyroid neoplasms with papillary-like nuclear features (NIFTPs), and 43.75% (n = 7) had benign disease. Aggressive features were detected in 33.33% of the malignant tumours. Malignant tumours were found to have a statistically significant higher allele frequency (AF). The aggressive nodules were all poorly differentiated thyroid carcinomas (PDTCs) with copy number alterations (CNAs) and the highest AFs.

Cancer Risk Associated With PTEN Pathogenic Variants Identified Using Multigene Hereditary Cancer Panel Testing

PURPOSE

PTEN-associated clinical syndromes such as Cowden syndrome (CS) increase cancer risk and have historically been diagnosed based upon phenotypic criteria. Because not all patients clinically diagnosed with CS have PTEN pathogenic variants (PVs), and not all patients with PTEN PVs have been clinically diagnosed with CS, the cancer risk conferred by PTEN PVs calculated from cohorts of patients with clinical diagnoses of CS/CS-like phenotypes may be inaccurate.

METHODS

We assessed a consecutive cohort of 727,091 individuals tested clinically for hereditary cancer risk, with a multigene panel between September 2013 and February 2022. Multivariable logistic regression models accounting for personal and family cancer history, age, sex, and ancestry were used to quantify disease risks associated with PTEN PVs.

RESULTS

PTEN PVs were detected in 0.027% (193/727,091) of the study population, and were associated with a high risk of female breast cancer (odds ratio [OR], 7.88; 95% CI, 5.57 to 11.16; P = 2.3 × 10^-31), endometrial cancer (OR, 13.51; 95% CI, 8.77 to 20.83; P = 4.2 × 10^-32), thyroid cancer (OR, 4.88; 95% CI, 2.64 to 9.01; P = 4.0 × 10^-7), and colon polyposis (OR, 31.60; CI, 15.60 to 64.02; P = 9.0 × 10^-22). We observed modest evidence suggesting that PTEN PVs may be associated with ovarian cancer risk (OR, 3.77; 95% CI, 1.71 to 8.32; P = 9.9 × 10^-4). Among patients with similar personal/family history and ancestry, every 5-year increase in age of diagnosis decreased the likelihood of detecting a PTEN PV by roughly 60%.

CONCLUSION

We demonstrate that PTEN PVs are associated with significantly increased risk for a range of cancers. Together with the observation that PTEN PV carriers had earlier disease onset relative to otherwise comparable noncarriers, our results may guide screening protocols, inform risk-management strategies, and warrant enhanced surveillance approaches that improve clinical outcomes for PTEN PV carriers, regardless of their clinical presentation.