Genetic basis of Cowden syndrome and its implications for clinical practice and risk management

Analysis of the loss of phosphatase and tensin homolog expression in thyroid tissue for the diagnosis of Cowden syndrome

BACKGROUND

Cowden syndrome is an autosomal-dominant disorder caused by a germline phosphatase and tensin homolog mutation, giving rise to several tumors with an aggressive clinical course. In the thyroid, there are certain histologic criteria that could be related to this syndrome that could be useful for its early detection. We sought to analyze the loss of phosphatase and tensin homolog in thyroid histologic pieces with certain histologic criteria and to determine the percentage of patients diagnosed with Cowden syndrome with this methodology.

METHODS

Five hundred thirty-five thyroid specimens collected were retrospectively analyzed (2017-2020). Those samples that presented certain histologic criteria were studied for loss of phosphatase and tensin homolog expression. Patients with loss of expression underwent a clinical study to rule out dermatologic or other lesions compatible with Cowden syndrome. Patients with positive clinical study were referred for genetic study.

RESULTS

The phosphatase and tensin homolog study was performed in 6.7% (n = 36) of the thyroidectomy samples, showing loss of expression in 22% (n = 8); the most frequent histologic finding was the presence of multiple monomorphous adenomatous nodules. The samples with loss of expression showed more diffuse oncocytic changes. Of the 8 patients with loss of expression, 5 showed dermatologic lesions that could be associated with Cowden syndrome and 1 had a history of macrocephaly. These patients were referred for genetic study, being positive for Cowden syndromein in one quarter of the cases (n = 2).

CONCLUSION

The immunohistochemical study of phosphatase and tensin homolog in pieces of thyroidectomies with histologic criteria suggestive of Cowden syndrome can help in its early diagnosis.

Establishment of a trastuzumab-resistant extramammary Paget disease model: loss of PTEN as a potential mechanism

BACKGROUND/OBJECTIVES

Extramammary Paget disease (EMPD) is a rare, cutaneous intraepithelial adenocarcinoma typically treated with wide local excision. Unfortunately, a number of patients with metastases show poor responses to chemotherapy. While some studies have explored trastuzumab's effectiveness against EMPD positive for human epidermal growth factor receptor 2 (HER2), trastuzumab resistance (TR) may emerge after anti-HER2 therapy.

METHODS/SUBJECTS

In this study, we established TR EMPD patient-derived xenografts (PDX) that replicated the histological and HER2 expression traits of naive EMPD tumours.

RESULTS

Cancer gene analyses revealed a loss of the PTEN gene in TR tumours, which was further confirmed by immunohistochemical staining and immunoblotting to test for protein expression levels. Reduced PTEN levels correlated with increased protein kinase B (Akt) phosphorylation and p27 downregulation, suggesting a potential mechanism for trastuzumab resistance in EMPD cells. In the trastuzumab-sensitive EMPD-PDX mouse model, PTEN inhibitors partially restored trastuzumab-mediated tumour regression. The TR EMPD-PDX responded favourably to targeted therapy (lapatinib, abemaciclib, palbociclib) and chemotherapy (eribulin, docetaxel, trastuzumab deruxtecan).

CONCLUSIONS

This study demonstrates an innovative TR EMPD-PDX model and introduces promising antineoplastic effects with various treatments for TR EMPD tumours.

Cowden Syndrome: A Rare Cause of Intestinal Polyposis

Cowden syndrome (CS) is a rare autosomal dominant genodermatosis disorder. This disease is characterized by the development of several hamartomata lesions in a variety of tissues from all three embryonic layers. The most well-known hamartomata are those of the gastrointestinal system, which represent one of the major criteria for the diagnosis of CS. Yet, the most frequent initial presenting symptom of the disease is thought to be mucocutaneous symptoms such as trichilemmomas, acral keratosis, and oral papilloma. Early diagnosis and management are essential to improving the quality of life for patients with CS as this disorder predisposes them to cancers such as thyroid, breast, gastrointestinal, and endometrial cancers. This report presents a rare case of CS in a Bahraini child who presented with macrocephaly and had numerous intestinal polyposis. Genetic testing using whole exome sequencing confirmed the diagnosis, identifying a pathogenic de novo phosphatase and tensin homolog gene (PTEN) variant (Chr10 NM_000314.8: c.17_18del p.(Lys6Argfs*4)) in a heterozygous state. This variant has been confirmed by Sanger sequencing.

Hereditary Gastrointestinal Tumor Syndromes: When Risk Comes with Your Genes

Despite recent campaigns for screening and the latest advances in cancer therapy and molecular biology, gastrointestinal (GI) neoplasms remain among the most frequent and lethal human tumors. Most GI neoplasms are sporadic, but there are some well-known familial syndromes associated with a significant risk of developing both benign and malignant GI tumors. Although some of these entities were described more than a century ago based on clinical grounds, the increasing molecular information obtained with high-throughput techniques has shed light on the pathogenesis of several of them. The vast amount of information gained from next-generation sequencing has led to the identification of some high-risk genetic variants, although others remain to be discovered. The opportunity for genetic assessment and counseling in these families has dramatically changed the management of these syndromes, though it has also resulted in significant psychological distress for the affected patients, especially those with indeterminate variants. Herein, we aim to summarize the most relevant hereditary cancer syndromes involving the stomach and colon, with an emphasis on new molecular findings, novel entities, and recent changes in the management of these patients.

Australian healthcare professionals' perspectives on genetic counseling and genetic diagnosis in vascular anomalies

Genomic technologies are now utilized for the genetic diagnosis of vascular anomalies. This provides the opportunity for genetic counselors to make a significant contribution to patient care for this complex disease. The aim of this study was to explore Australian healthcare professionals' perspectives on the relatively recent integration of molecular diagnostic testing for vascular anomalies, with or without genetic counseling support. Nine semi-structured interviews were conducted with Australian healthcare professionals involved in the provision of care for individuals with vascular anomalies. Thematic analysis identified six themes: (1) Molecular diagnosis is beneficial; (2) psychosocial needs can motivate families to pursue a molecular diagnosis; (3) molecular genetic testing for vascular anomalies is complex; (4) genetic service provision is not a one size fits all; (5) a client-centered approach for genetic service provision can go a long way; and (6) the value of genetic counselors. Based on our findings, implementation of a vascular anomalies genetic diagnostic program inclusive of genetic counseling may be challenging, yet such programs are likely to benefit both patients and their families, as well as healthcare professionals. As this paradigm shift unfolds, genetic counselors have an opportunity to contribute to the vascular anomaly field by educating healthcare professionals and patients, by participating in multidisciplinary clinics to support complex cases and by raising awareness regarding their practice and potential contributions.

Treatment and Diagnostic Approach for Lhermitte-Duclos Disease and Suspected Cowden Syndrome

Lhermitte-Duclos disease (LDD) is a rare entity, which may or may not be associated with Cowden syndrome (CS). The authors present a 26-year-old male with a history of emergency treatment due to acute obstructive hydrocephalus and apparent Chiari malformation. In posterior evaluation, mild cerebellar symptoms, mucocutaneous lesions, and a left hemispheric cerebellar lesion were evident. Initially, with the clinical evidence and the radiological study report of a cerebellar tiger-striped lesion, LDD with associated CS was suspected, and a genetic protocol was performed. The protocol included an endoscopy and thyroid ultrasound, and with symptom progression, a new neurosurgical procedure was performed. To complete the approach, we used the clinical criteria for PTEN hamartoma tumor syndrome established in 2013, and CS was diagnosed in the patient. In patients with radiological and clinical suspicion of LDD and CS, it should be mandatory to investigate the presence of other types of tumors due to their association with PTEN hamartomatous tumor syndrome, and in the absence of genetic study, the clinical criteria previously established in the literature should be sufficient to establish the diagnosis.

PTEN hamartoma tumour syndrome: case report based on data from the Iranian hereditary colorectal cancer registry and literature review

BACKGROUND

PTEN hamartoma tumour syndrome (PHTS) is a rare hereditary disorder caused by germline pathogenic mutations in the PTEN gene. This study presents a case of PHTS referred for genetic evaluation due to multiple polyps in the rectosigmoid area, and provides a literature review of PHTS case reports published between March 2010 and March 2022.

CASE PRESENTATION

A 39-year-old Iranian female with a family history of gastric cancer in a first-degree relative presented with minimal bright red blood per rectum and resistant dyspepsia. Colonoscopy revealed the presence of over 20 polyps in the rectosigmoid area, while the rest of the colon appeared normal. Further upper endoscopy showed multiple small polyps in the stomach and duodenum, leading to a referral for genetic evaluation of hereditary colorectal polyposis. Whole-exome sequencing led to a PHTS diagnosis, even though the patient displayed no clinical or skin symptoms of the condition. Further screenings identified early-stage breast cancer and benign thyroid nodules through mammography and thyroid ultrasound.

METHOD AND RESULTS OF LITERATURE REVIEW

A search of PubMed using the search terms "Hamartoma syndrome, Multiple" [Mesh] AND "case report" OR "case series" yielded 43 case reports, predominantly in women with a median age of 39 years. The literature suggests that patients with PHTS often have a family history of breast, thyroid and endometrial neoplasms along with pathogenic variants in the PTEN/MMAC1 gene. Gastrointestinal polyps are one of the most common signs reported in the literature, and the presence of acral keratosis, trichilemmomas and mucocutaneous papillomas are pathognomonic characteristics of PHTS.

CONCLUSION

When a patient presents with more than 20 rectosigmoid polyps, PHTS should be considered. In such cases, it is recommended to conduct further investigations to identify other potential manifestations and the phenotype of PHTS. Women with PHTS should undergo annual mammography and magnetic resonance testing for breast cancer screening from the age of 30, in addition to annual transvaginal ultrasounds and blind suction endometrial biopsies.

Hamartomatous polyps: Diagnosis, surveillance, and management

Hereditary polyposis syndrome can be divided into three categories: Ade-nomatous, serrated, and hamartomatous polyps. Hamartomatous polyps, malformations of normal tissue presenting in a disorganized manner, are characterized by an autosomal dominant inheritance pattern. These syndromes exhibit hamartomatous gastrointestinal polyps in conjunction to extra-intestinal manifestations, which require conscientious and diligent monitoring. Peutz-Jeghers syndrome, Cowden syndrome, and juvenile polyposis syndrome are the most common displays of hamartomatous polyposis syndrome (HPS). Diagnosis can be pursued with molecular testing and endoscopic sampling. Early identification of these autosomal dominant pathologies allows to optimize malignancy sur-veillance, which helps reduce morbidity and mortality in both the affected patient population as well as at-risk family members. Endoscopic surveillance is an important pillar of prognosis and monitoring, with many patients eventually requiring surgical intervention. In this review, we discuss the diagnosis, surveillance, and management of HPS.

Nuclear PTEN's Functions in Suppressing Tumorigenesis: Implications for Rare Cancers

Phosphatase and tensin homolog (PTEN) encodes a tumor-suppressive phosphatase with both lipid and protein phosphatase activity. The tumor-suppressive functions of PTEN are lost through a variety of mechanisms across a wide spectrum of human malignancies, including several rare cancers that affect pediatric and adult populations. Originally discovered and characterized as a negative regulator of the cytoplasmic, pro-oncogenic phosphoinositide-3-kinase (PI3K) pathway, PTEN is also localized to the nucleus where it can exert tumor-suppressive functions in a PI3K pathway-independent manner. Cancers can usurp the tumor-suppressive functions of PTEN to promote oncogenesis by disrupting homeostatic subcellular PTEN localization. The objective of this review is to describe the changes seen in PTEN subcellular localization during tumorigenesis, how PTEN enters the nucleus, and the spectrum of impacts and consequences arising from disrupted PTEN nuclear localization on tumor promotion. This review will highlight the immediate need in understanding not only the cytoplasmic but also the nuclear functions of PTEN to gain more complete insights into how important PTEN is in preventing human cancers.

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.

Cowden Disease: A Review

ABSTRACT

PTEN hamartoma tumor syndrome (PTHS) includes diseases with germline pathogenic variants in the PTEN gene. Cowden syndrome is included in this syndrome . PTEN (phosphatase and tensin homolog) is a tumor suppressor gene located on chromosome 10q22-23; nearly 60%-90% of pathogenic variants are inherited. Cowden syndrome is a rare autosomic dominant condition, affecting approximately 1/200,000 people worldwide. Patients present benign and, malignant neoplasms in multiple organs, mostly breast and thyroid. The skin is the organ affected most consistently by Cowden disease. It is an autosomal dominant condition, characterized clinically by the presence of innumerable verrucous lesions on the skin. Interpretations of histopathologic findings in the cutaneous and mucosal lesions continue to be a matter of debate.

Cowden Syndrome Case Report: Use of an Ultrasonic Surgical Aspirator for Cosmetic Removal of Lip Hamartomas

Cowden syndrome (CS) is an autosomal dominant condition that is relatively rare. CS patients can have tumors derived from all three germlines. They can present with mucocutaneous hamartomas or other benign tumors, and have an increased risk of malignancies of the thyroid, breast, kidney, GI tract, and skin. In our clinic, a 40-year-old CS patient presented for thyroidectomy after fine needle aspiration was suspicious for papillary thyroid carcinoma (PTC). Another major concern was the cosmetic appearance of her lips, which were diffusely covered with small hamartomas. We were able to remove these in a novel manner using a cavitron ultrasonic surgical aspirator (CUSA; Integra Lifesciences, Princeton, NJ, USA). Using the CUSA tangential to the lip surface allowed for removal of the hamartomas in a way that created a smooth and cosmetically appealing outcome for the patient. The use of an ultrasonic surgical aspirator is a novel way to cosmetically treat hamartomas of the lip for CS patients.

AMBRA1 p.Gln30Arg Mutation, Identified in a Cowden Syndrome Family, Exhibits Hyperproliferative Potential in hTERT-RPE1 Cells

Cowden syndrome (CS) is a rare autosomal dominant disorder associated with multiple hamartomatous and neoplastic lesions in various organs. Most CS patients have been found to have germline mutations in the PTEN tumor suppressor. In the present study, we investigated the causative gene of CS in a family of PTEN (phosphatase and tensin homolog deleted on chromosome 10) -negative CS patients. Whole exome sequencing analysis revealed AMBRA1 (Autophagy and Beclin 1 Regulator 1) as a novel candidate gene harboring two germline variants: p.Gln30Arg (Q30R) and p.Arg1195Ser (R1195S). AMBRA1 is a key regulator of the autophagy signaling network and a tumor suppressor. To functionally validate the role of AMBRA1 in the clinical manifestations of CS, we generated AMBRA1 depletion and Q30R mutation in hTERT-RPE1 (humanTelomerase Reverse Transcriptase-immortalized Retinal Pigmented Epithelial cells) using the CRISPR-Cas9 gene editing system. We observed that both AMBRA1-depleted and mutant cells showed accumulation in the S phase, leading to hyperproliferation, which is a characteristic of hamartomatous lesions. Specifically, the AMBRA1 Q30R mutation disturbed the G1/S transition of cells, leading to continuous mitotic entry of mutant cells, irrespective of the extracellular condition. From our analysis of primary ciliogenesis in these cells, we speculated that the mitotic entry of AMBRA1 Q30R mutants could be due to non-functional primary cilia that lead to impaired processing of extracellular sensory signals. Additionally, we observed a situs inversus phenotype in ambra1-depleted zebrafish, a developmental abnormality resulting from dysregulated primary ciliogenesis. Taken together, we established that the AMBRA1 Q30R mutation that we observed in CS patients might play an important role in inducing the hyperproliferative potential of cells through regulating primary ciliogenesis.

Epidemiology and Prevention of Renal Cell Carcinoma

With 400,000 diagnosed and 180,000 deaths in 2020, renal cell carcinoma (RCC) accounts for 2.4% of all cancer diagnoses worldwide. The highest disease burden developed countries, primarily in Europe and North America. Incidence is projected to increase in the future as more countries shift to Western lifestyles. Risk factors for RCC include fixed factors such as gender, age, and hereditary diseases, as well as intervening factors such as smoking, obesity, hypertension, diabetes, diet and alcohol, and occupational exposure. Intervening factors in primary prevention, understanding of congenital risk factors and the establishment of early diagnostic tools are important for RCC. This review will discuss RCC epidemiology, risk factors, and biomarkers involved in reducing incidence and improving survival.

New Trends in the Detection of Gynecological Precancerous Lesions and Early-Stage Cancers

The prevention and early diagnostics of precancerous stages are key aspects of contemporary oncology. In cervical cancer, well-organized screening and vaccination programs, especially in developed countries, are responsible for the dramatic decline of invasive cancer incidence and mortality. Cytological screening has a long and successful history, and the ongoing implementation of HPV triage with increased sensitivity can further decrease mortality. On the other hand, endometrial and ovarian cancers are characterized by a poor accessibility to specimen collection, which represents a major complication for early diagnostics. Therefore, despite relatively promising data from evaluating the combined effects of genetic variants, population screening does not exist, and the implementation of new biomarkers is, thus, necessary. The introduction of various circulating biomarkers is of potential interest due to the considerable heterogeneity of cancer, as highlighted in this review, which focuses exclusively on the most common tumors of the genital tract, namely, cervical, endometrial, and ovarian cancers. However, it is clearly shown that these malignancies represent different entities that evolve in different ways, and it is therefore necessary to use different methods for their diagnosis and treatment.

Feasibility of genetic testing for cancer risk assessment programme in Nigeria

Background

A high frequency of BRCA mutations has been established in Nigerian breast cancer (BC) patients. Recently, patients’ and first-degree relatives’ interest have been raised on cancer genetic risk assessment through our awareness activities in Nigeria. This led to the emergence of nurse-led cancer genetic counselling (CGC) and testing aimed at providing standard-of-care for individuals at increased risk of hereditary breast and ovarian cancers.

Methods

In June 2018, CGC and testing of patients with BC and ovarian cancer (OC) commenced in collaboration with Color Genomics Inc. for a 30-panel gene testing. Previously trained nurses in CGC at the University College Hospital, Ibadan offered genetic counselling (GC) to willing patients with BC and gynaecological cancer in four out-patient oncology clinics and departments for the pilot study. Consultation consisted of CGC, patient’s history, pedigree and sample collection for genetic testing (GT).

Results

Forty-seven patients – 40 with BC, five with OC and two with endometrial cancer received GC, and all chose to undergo GT. The average age at testing was 48.2 ± 12.1 years. Eight women reported a known family cancer history and there were more perceived benefits than barriers to GT with the patients experiencing the desire for none of their relative to have cancer. Results revealed no mutations in 27 (57.4%), 16 (4.0%) variants of unknown significance and 4 (8.5%) pathogenic mutations.

Conclusion

Personalised cancer care utilises GC and testing for cancer risk assessment towards prevention and early detection in high risk women. The study indicates the necessity of expanded cancer genetic services for integration into patient care and cancer prevention.

PTEN Hamartoma Tumor Syndrome/Cowden Syndrome: Genomics, Oncogenesis, and Imaging Review for Associated Lesions and Malignancy

Simple Summary

In this manuscript, we present the associated imaging findings and imaging screening recommendations. Knowledge of the types of cancers commonly seen in Cowden syndrome and their imaging findings can aid in early tumor recognition during cancer screening to help ensure near-normal life spans in Cowden syndrome patients.

Abstract

PTEN hamartoma tumor syndrome/Cowden syndrome (CS) is a rare autosomal dominant syndrome containing a germline PTEN mutation that leads to the development of multisystem hamartomas and oncogenesis. Benign tumors such as Lhermitte–Duclos disease and malignant tumors involving the breast, thyroid, kidneys, and uterus are seen in CS. Radiologists have an integral role in the comanagement of CS patients. We present the associated imaging findings and imaging screening recommendations. Knowledge of the types of cancers commonly seen in CS and their imaging findings can aid in early tumor recognition during cancer screening to help ensure near-normal life spans in CS patients.

Orofacial Manifestations Assisting the Diagnosis of Cowden Syndrome in a Middle-Aged Patient: Case Report and Literature Overview

Middle-aged and old adults (≥ 50 years) diagnosed with Cowden syndrome (CS) with orofacial manifestations are uncommon. We describe a case of CS in a 53-year-old female showing "narrow bird-like" face, macrocephaly, acral keratoses, oral candidiasis, burning in the mouth, and multiple asymptomatic papillomatous lesions with a cobblestone pattern distributed on the alveolar ridge, tongue, buccal mucosa, and commissure. The histopathological features of lesions of the oral mucosa were those of papillary fibroepithelial hyperplasia. Immunohistochemistry revealed strong positivity for PTEN and p53 in most epithelial cells, while the expression of Bcl-2, S-100, and Ki-67 was weak/negative. According to a review conducted in PubMed, Web of Science, Embase, and Scopus for the analysis of reports of CS individuals ≥ 50 years with orofacial manifestations, 56 cases have been described in literature. Predilection for women was observed, with a female:male ratio of 2.3:1. Thirty-five (62.5%) individuals developed some malignant neoplasms. Oral health providers should be aware of the orofacial aspects of CS, including multiple papillomatosis, which can be an important criterion for diagnosis. Since malignancies may occur in older adults with CS, the need for strict surveillance is necessary. The present case has been under follow-up for 7 years without evidence of other manifestations.

Current update on the molecular genetics and management of hereditary ovarian cancers: a primer for radiologists

More than one-fifth of ovarian cancers are hereditary, with most of them caused by BRCA genes. Malignant ovarian neoplasms are primarily epithelial tumors, a heterogeneous group of tumors with variable genetic backgrounds that translate into different biologic behaviors and morphologic features. Radiologists play an increasingly important role in the diagnosis and management of oncology patients. Familiarity with hereditary ovarian cancers will have a positive impact on patient management and radiologists' involvement in the multidisciplinary approach needed for this delicate patient population. In this paper, we review the basic histologic and genetic backgrounds of ovarian tumors with an emphasis on hereditary ovarian cancers, as well as the effects that these factors have on patient workup, primarily with regard to imaging studies.

Genetic Mutations and Variants in the Susceptibility of Familial Non-Medullary Thyroid Cancer

Thyroid cancer is the most frequent endocrine malignancy with the majority of cases derived from thyroid follicular cells and caused by sporadic mutations. However, when at least two or more first degree relatives present thyroid cancer, it is classified as familial non-medullary thyroid cancer (FNMTC) that may comprise 3-9% of all thyroid cancer. In this context, 5% of FNMTC are related to hereditary syndromes such as Cowden and Werner Syndromes, displaying specific genetic predisposition factors. On the other hand, the other 95% of cases are classified as non-syndromic FNMTC. Over the last 20 years, several candidate genes emerged in different studies of families worldwide. Nevertheless, the identification of a prevalent polymorphism or germinative mutation has not progressed in FNMTC. In this work, an overview of genetic alteration related to syndromic and non-syndromic FNMTC is presented.

Urinary Biomarkers and Their Potential for the Non-Invasive Detection of Endometrial Cancer

Endometrial cancer is the most common malignancy of the female genital tract and its incidence is rising in parallel with the mounting prevalence of obesity. Early diagnosis has great potential to improve outcomes as treatment can be curative, especially for early stage disease. Current tests and procedures for diagnosis are limited by insufficient accuracy in some and unacceptable levels of invasiveness and discomfort in others. There has, therefore, been a growing interest in the search for sensitive and specific biomarkers for endometrial cancer detection based on non-invasive sampling methodologies. Urine, the prototype non-invasive sample, is attractive for biomarker discovery as it is easily accessible and can be collected repeatedly and in quantity. Identification of urinary biomarkers for endometrial cancer detection relies on the excretion of systemic biomarkers by the kidneys or urinary contamination by biomarkers shed from the uterus. In this review, we present the current standing of the search for endometrial cancer urinary biomarkers based on cytology, genomic, transcriptomic, proteomic, and metabolomic platforms. We summarize the biomarker candidates and highlight the challenges inherent in urinary biomarker discovery. We review the various technologies with promise for biomarker detection and assess these novel approaches for endometrial cancer biomarker research.

Mosaicism in Patients With Colorectal Cancer or Polyposis Syndromes: A Systematic Review

BACKGROUND & AIMS

Somatic mosaicism, in which variants arise post-zygotically and are therefore not present in all cells in the body, may be an underestimated cause of colorectal cancer (CRC) and polyposis syndromes. We performed a systematic review to provide a comprehensive overview of somatic mosaicism in patients with CRC and polyposis syndromes.

METHODS

We searched PubMed through March 2018 to identify reports of mosaicism in patients with CRC or polyposis syndromes. We divided the final set of studies into 3 subgroups describing APC mosaicism, mosaicism in other CRC susceptibility genes, and epigenetic mosaicism.

RESULTS

Of the 232 articles identified in our systematic search, 46 met the criteria for further analysis. Of these, 35 studies described mosaic variants or epimutations in patients with CRC or polyposis syndromes. Nineteen studies described APC mosaicism, comprising a total of 57 patients. Six described mosaicism in genes associated with familial CRC syndromes, such as Lynch and Cowden syndromes. Ten studies described epigenetic mosaicism, sometimes resulting from a germline variant (such as deletion of EPCAM).

CONCLUSIONS

We found that somatic mosaicism is underdiagnosed but critical for determining the clinical management of patients with de novo polyposis who possibly carry mosaic APC variants, and present a decision tree for the clinical management of these patients. Mosaicism in genes associated with susceptibility to CRC contributes to development of other familial CRC syndromes. Heritable epigenetic mosaicism is likely underestimated and could have a dominant pattern of inheritance. However, the inheritance of primary mosaic epimutations, without an underlying genetic cause, is complex and not fully understood.

Cowden syndrome complicated by schizophrenia: A first clinical report

Patients with Cowden syndrome exhibit mucocutaneous lesions, hamartomatous polyposis of the gastrointestinal tract, and macrocephaly, often complicated by malignant tumors, such as breast, thyroid, and uterine cancers. Autism spectrum and epilepsy have been known as neuropsychiatric symptoms associated with Cowden syndrome; however, to the best of our knowledge, there is no report on cases complicated by schizophrenia. Here, we report a first case of Cowden syndrome complicated by schizophrenia. A 49-year-old Japanese woman started experiencing auditory hallucinations in her teens. She had left breast cancer at the age of 34 years, and right breast cancer at the age of 37 years, all of which were surgically treated. She was also being treated by oral medications for Hashimoto's disease. On consulting her previous doctor for abnormal uterine bleeding that lasted for a year, she was diagnosed with endometrial cancer. However, immediately before surgery, her auditory hallucinations and paranoid delusions became severe, and she was referred to our hospital for detailed examination and treatment. No abnormalities were found on head MRI, and she was diagnosed with schizophrenia on the basis of neuropsychiatric examination findings. After her psychiatric symptoms were controlled by 2 mg of risperidone, she underwent surgery for endometrial cancer. Although there was no apparent family history, physical findings including macrocephaly and papillomatous skin lesions together with her past medical history of multiple malignant tumors suggested Cowden syndrome. Postoperatively, genetic testing revealed a pathogenic variant c.655C > T; p. Gln219* (NM_000314.4) in PTEN, leading to the confirmation of the diagnosis of Cowden syndrome.

Rho GTPases in Gynecologic Cancers: In-Depth Analysis toward the Paradigm Change from Reactive to Predictive, Preventive, and Personalized Medical Approach Benefiting the Patient and Healthcare

Rho guanosine triphospatases (GTPases) resemble a conserved family of GTP-binding proteins regulating actin cytoskeleton dynamics and several signaling pathways central for the cell. Rho GTPases create a so-called Ras-superfamily of GTPases subdivided into subgroups comprising at least 20 members. Rho GTPases play a key regulatory role in gene expression, cell cycle control and proliferation, epithelial cell polarity, cell migration, survival, and apoptosis, among others. They also have tissue-related functions including angiogenesis being involved in inflammatory and wound healing processes. Contextually, any abnormality in the Rho GTPase function may result in severe consequences at molecular, cellular, and tissue levels. Rho GTPases also play a key role in tumorigenesis and metastatic disease. Corresponding mechanisms include a number of targets such as kinases and scaffold/adaptor-like proteins initiating GTPases-related signaling cascades. The accumulated evidence demonstrates the oncogenic relevance of Rho GTPases for several solid malignancies including breast, liver, bladder, melanoma, testicular, lung, central nervous system (CNS), head and neck, cervical, and ovarian cancers. Furthermore, Rho GTPases play a crucial role in the development of radio- and chemoresistance e.g. under cisplatin-based cancer treatment. This article provides an in-depth overview on the role of Rho GTPases in gynecological cancers, highlights relevant signaling pathways and pathomechanisms, and sheds light on their involvement in tumor progression, metastatic spread, and radio/chemo resistance. In addition, insights into a spectrum of novel biomarkers and innovative approaches based on the paradigm shift from reactive to predictive, preventive, and personalized medicine are provided.

Endometrial cancer prevention in high-risk women

Endometrial cancer (EC) is the most common gynaecological malignancy, and its incidence is rising alongside the growing prevalence of obesity. Effective risk-reducing interventions hijacking the key mechanisms driving endometrial carcinogenesis may affect EC diagnoses if aimed at those at greatest risk. An understanding of the key risk factors and their role in tumourigenesis is critical in developing such prevention strategies. In this review, we summarise the major risk factors for EC and the evidence for available risk-reducing interventions in high-risk women. We suggest potential prevention strategies and make a case for the need for risk prediction models that identify specific groups of women at a particularly high risk of EC for whom risk-reducing interventions are likely to have a significant impact.

Estrogen Signaling in Endometrial Cancer: a Key Oncogenic Pathway with Several Open Questions

Endometrial cancer is the most common gynecological cancer in the developed world, and it is one of the few cancer types that is becoming more prevalent and leading to more deaths in the USA each year. The majority of endometrial tumors are considered to be hormonally driven, where estrogen signaling through estrogen receptor α (ER) acts as an oncogenic signal. The major risk factors and some treatment options for endometrial cancer patients emphasize a key role for estrogen signaling in the disease. Despite the strong connections between estrogen signaling and endometrial cancer, important molecular aspects of ER function remain poorly understood; however, progress is being made in our understanding of estrogen signaling in endometrial cancer. Here, we discuss the evidence for the importance of estrogen signaling in endometrial cancer, details of the endometrial cancer-specific actions of ER, and open questions surrounding estrogen signaling in endometrial cancer.

The Rare Neurocutaneous Disorders: Update on Clinical, Molecular, and Neuroimaging Features

Phakomatoses, also known as neurocutaneous disorders, comprise a vast number of entities that predominantly affect structures originated from the ectoderm such as the central nervous system and the skin, but also the mesoderm, particularly the vascular system. Extensive literature exists about the most common phakomatoses, namely neurofibromatosis, tuberous sclerosis, von Hippel-Lindau and Sturge-Weber syndrome. However, recent developments in the understanding of the molecular underpinnings of less common phakomatoses have sparked interest in these disorders. In this article, we review the clinical features, current pathogenesis, and modern neuroimaging findings of melanophakomatoses, vascular phakomatoses, and other rare neurocutaneous syndromes that may also include tissue overgrowth or neoplastic predisposition.

Early Onset Multiple Primary Tumors in Atypical Presentation of Cowden Syndrome Identified by Whole-Exome-Sequencing

A family with an aggregation of rare early onset multiple primary tumors has been managed in our oncogenetics department: the proband developed four early onset carcinomas between ages 31 and 33 years, including acral melanoma, bilateral clear cell renal carcinoma (RC), and follicular variant of papillary thyroid carcinoma. The proband's parent developed orbital lymphoma and small intestine mucosa-associated lymphoid tissue (MALT) lymphoma between 40 and 50 years old. Whole-exome-sequencing (WES) of the nuclear family (proband, parents, and sibling) identified in the proband a de novo deleterious heterozygous mutation c.1003C > T (p.Arg335^∗) in the phosphatase and tensin homolog (PTEN) gene. Furthermore, WES allowed analysis of the nuclear family's genetic background, and identified deleterious variants in two candidate modifier genes: CEACAM1 and MIB2. CEACAM1, a tumor suppressor gene, presents loss of expression in clear cell RC and is involved in proliferation of B cells. It could explain in part the phenotype of proband's parent and the occurrence of clear cell RC in the proband. Deleterious mutations in the MIB2 gene are associated with melanoma invasion, and could explain the occurrence of melanoma in the proband. Cowden syndrome is a hereditary autosomal dominant disorder associated with increased risk of muco-cutaneous features, hamartomatous tumors, and cancer. This atypical presentation, including absence of muco-cutaneous lesions, four primary early onset tumors and bilateral clear cell RC, has not been described before. This encourages including the PTEN gene in panel testing in the context of early onset RC, whatever the histological subtype. Further studies are required to determine the implication of CEACAM1 and MIB2 in the severity of Cowden syndrome in our proband and occurrence of early onset MALT lymphoma in a parent.

The PI3K Pathway in Human Disease

Phosphoinositide 3-kinase (PI3K) activity is stimulated by diverse oncogenes and growth factor receptors, and elevated PI3K signaling is considered a hallmark of cancer. Many PI3K pathway-targeted therapies have been tested in oncology trials, resulting in regulatory approval of one isoform-selective inhibitor (idelalisib) for treatment of certain blood cancers and a variety of other agents at different stages of development. In parallel to PI3K research by cancer biologists, investigations in other fields have uncovered exciting and often unpredicted roles for PI3K catalytic and regulatory subunits in normal cell function and in disease. Many of these functions impinge upon oncology by influencing the efficacy and toxicity of PI3K-targeted therapies. Here we provide a perspective on the roles of class I PI3Ks in the regulation of cellular metabolism and in immune system functions, two topics closely intertwined with cancer biology. We also discuss recent progress developing PI3K-targeted therapies for treatment of cancer and other diseases.

Lhermitte-Duclos disease associated to Cowden syndrome: de novo diagnosis and management of these extremely rare syndromes in a patient

A 36-year-old woman, with history of cutaneous papilomatosis and thyroid carcinoma presented with headache, transitory visual blurring and nausea. Funduscopy showed papilloedema. MRI showed a tumour of the right cerebellar hemisphere with a striated, tigroid pattern, typical of Lhermitte-Duclos disease (LDD). Significant clinical and perimetric improvements were noted after surgery and the follow-up did not reveal recurrences of the tumour. LDD is an extremely rare differential diagnosis of posterior fossa tumours. LDD and the history of thyroid carcinoma permitted us to diagnose Cowden syndrome (CS). We present a clinical case that supports the possibility of performing a preoperative diagnosis of LDD based on MRI features. We review the diagnosis and management of LDD and CS. This report highlights the importance of excluding CS after LDD diagnosis, of monitoring the optic nerve postoperatively using optical coherence tomography and of prompt treatment that can potentially prevent visual function loss.