Peutz-Jeghers syndrome

Device-assisted enteroscopy in the surveillance of intestinal hamartomas in Peutz-Jeghers syndrome

Background and study aims Peutz-Jeghers syndrome (PJS) is an autosomal-dominant genetic disorder characterized by the formation of hamartomatous polyps in the gastrointestinal tract. These polyps result in significant morbidity due to adverse events (AEs) including intestinal obstruction, bleeding, and malignancy. The aim of this study was to describe the role of device-assisted enteroscopy (DAE) in monitoring and prophylactic polypectomy within the small bowel. Patients and methods Electronic medical records were surveyed to identify all DAE procedures performed in patients with PJS at three US referral centers between January 1, 2007 and January 1, 2020. Individual charts were reviewed to collect and analyze specific data points. Primary end points included AEs associated with DAE-related polypectomy and the rate of laparotomy in PJS patients prior to, and following, index DAE. Secondary data points included patient characteristics, procedural details, and size/location/distribution of small bowel hamartomas. Results Twenty-three patients met our inclusion criteria. Of these, 18 (75%) had previously undergone small bowel surgery prior to index DAE. Between 2007 and 2020, 46 DAEs were performed in these patients with an average of one exam every 2.5 years. A total of 131 polypectomies were performed with an AE rate of 1.5%. None of our cohort required emergent surgery related to AEs of small bowel hamartomas over 336 years of aggregated follow-up. Conclusions Endoscopic management of small bowel polyps in patients with PJS using DAE is an effective strategy for prophylactic removal of hamartomas. DAE surveillance and endoscopic polypectomy is safe and may decrease the need for repeated laparotomy in patients with PJS.

[Management of the Peutz-Jeghers Syndrome]

The current evidence to guide management of Peutz-Jeghers Syndrome (PJS) is sparse. Here we summarise the European guidelines that were published in 2021 by the EHTG (European Hereditary Tumour Group), extended with new evidence on some aspects of clinical management that have been generated since then. EHTG with this revised guideline has updated and extended their own previous expert opinion guideline from 2010. For this purpose, all published literature was systematically screened and the level of evidence determined by using the GRADE methodology (Grading of Recommendations Assessment. Development and Evaluation). This was followed by a Delphi process and the consensus for a statement was achieved if the voting committee reached ≥ 80% approval.The only other more recently published guidelines encountered only addressed the clinical management of gastrointestinal and pancreatic manifestations of PJS. These recommendations were reviewed and adopted, since no further relevant literature was identified in the systematic literature search. However, additional questions were identified and formulated into recommendations after following the described process. It may be stated that 10 years after the predecessor guideline, new evidence has been sparse. As with all rare diseases, a call for more collaborative studies must here be made in order to improve patient management by addressing open clinical questions and generating collaborative evidence with increased case numbers, both nationally and internationally. With the limited published evidence, these European guidelines are the most current reference for management of PJS patients.

Changes of gut microbiota and short chain fatty acids in patients with Peutz-Jeghers syndrome

Peutz-Jeghers Syndromeis a rare autosomal dominant genetic disease characterized by gastrointestinal hamartomatous polyps and skin and mucous membrane pigmentation. The pathogenesis of PJS remains unclear; however, it may be associated with mutations in the STK11 gene, and there is currently no effective treatment available. The gut microbiota plays an important role in maintaining intestinal homeostasis in the human body, and an increasing number of studies have reported a relationship between gut microbiota and human health and disease. However, relatively few studies have been conducted on the gut microbiota characteristics of patients with PJS. In this study, we analyzed the characteristics of the gut microbiota of 79 patients with PJS using 16 S sequencing and measured the levels of short-chain fatty acids in the intestines. The results showed dysbiosis in the gut microbiota of patients with PJS, and decreased synthesis of short-chain fatty acids. Bacteroides was positively correlated with maximum polyp length, while Agathobacter was negatively correlated with age of onset. In addition, acetic acid, propionic acid, and butyric acid were positively correlated with the age of onset but negatively correlated with the number of polyps. Furthermore, the butyric acid level was negatively correlated with the frequency of endoscopic surgeries. In contrast, we compared the gut microbiota of STK11-positive and STK11-negative patients with PJS for the first time, but 16 S sequencing analysis revealed no significant differences. Finally, we established a random forest prediction model based on the gut microbiota characteristics of patients to provide a basis for the targeted diagnosis and treatment of PJS in the future.

Clinicopathologic comparison between sporadic and syndromic Peutz-Jeghers polyps

Peutz-Jeghers polyps (PJPs) are hamartomatous polyps that may define patients with Peutz-Jeghers syndrome (PJS), a rare inherited polyposis syndrome with high cancer risk. However, the clinical significance of 1-2 sporadic PJPs (without other PJS stigmata) regarding malignant potential and identification of new PJS probands is still unclear. We identified 112 patients with 524 histologically confirmed PJPs and categorized them based on polyp number into syndromic (n = 38) if ≥3 PJPs or diagnosed PJS, solitary (1 PJP, n = 61), and intermediate (2 PJPs, n = 13). Clinicopathologic features, including presence of dysplasia in the polyp and development of neoplasia in the patient, were compared on a per-patient and per-polyp basis. Whereas patients with solitary and intermediate PJPs were not different from each other, patients with syndromic PJPs were, in multivariate analysis, younger (P = .001) and more likely to develop neoplasia (P = .02) over a 62.6-months median follow-up than patients with sporadic PJPs. On an individual polyp basis, syndromic PJPs were more likely, in multivariate analysis, to occur in the small intestine (P < .001), but less likely to harbor metaplasia (P = .03) or dysplasia (P = .001), than sporadic PJPs. Dysplasia and metaplasia were more likely in larger PJPs, by multivariate analysis (P = .007 and P < .001, respectively). These data suggest that strict criteria for PJS (including ≥3 PJPs), as currently used, stratify patients into distinct groups with significant differences in clinicopathologic parameters, particularly regarding risk of neoplasia. However, sporadic PJPs exhibit characteristics such as dysplasia and are thus important to recognize and diagnose but perhaps as heralding only a forme fruste PJS.

Endoscopic resection for a solitary Peutz‐Jeghers type polyp in the duodenum: A case report with literature review

A 68‐year‐old female patient was referred to our hospital with a 30‐mm polyp in the second portion of the duodenum found via esophagogastroduodenoscopy. The polyp had an irregular, lobular surface and a thick stalk. In addition, white dots were detected on the surface. Magnifying endoscopy with narrow‐band imaging showed a white material deep in the loop‐shaped microvessels on the white dots. Endoscopic ultrasonography showed a hypoechoic elevated lesion from the mucosal layer, and a feeding vessel traversing the stalk to supply the head of the polyp. Endoscopic biopsy did not provide a definitive diagnosis. Endoscopic resection was conducted for a definitive diagnosis and treatment. The resected specimen showed a branching bundle of smooth muscle fibers covered by hyperplastic mucosa, consistent with a hamartomatous polyp. The patient had no mucocutaneous pigmentation or familial history of the hamartomatous polyp. The polyp was finally diagnosed as a solitary Peutz‐Jeghers‐type polyp. No recurrence has been observed for seven years postoperatively.

Endoscopic Surveillance in Patients with the Highest Risk of Gastric Cancer: Challenges and Solutions

Gastric cancer is one of the most significant causes of cancer-related morbidity and mortality worldwide. Recognized modifiable risk factors include Helicobacter pylori infection, geographic location, select dietary factors, tobacco use and alcohol consumption. In addition, multiple hereditary cancer predisposition syndromes are associated with significantly elevated gastric cancer risk. Endoscopic surveillance in hereditary gastric cancer predisposition syndromes has the potential to identify gastric cancer at earlier and more treatable stages, as well as to prevent development of gastric cancer through identification of precancerous lesions. However, much uncertainty remains regarding use of endoscopic surveillance in hereditary gastric cancer predisposition syndromes, including whether or not it should be routinely performed, the surveillance interval and age of initiation, cost-effectiveness, and whether surveillance ultimately improves survival from gastric cancer for these high-risk individuals. In this review, we outline the hereditary gastric cancer predisposition syndromes associated with the highest gastric cancer risks. Additionally, we cover current evidence and guidelines addressing hereditary gastric cancer risk and surveillance in these syndromes, along with current challenges and limitations that emphasize a need for continued research in this field.

Peutz–Jeghers syndrome revealed by recurrent small bowel intussusceptions in children: A case report

Peutz–Jeghers syndrome is a rare but potentially life‐threating syndrome. We report here the case of a young girl who presented recurrent small bowel intussusceptions. Laparotomy exploration showed many jejunal polyps leading to jejunojejunal intussusceptions. These were removed via mini enterotomies and pathological examination concluded to Peutz–Jeghers polyps.

Diagnosis and Management of Cancer Risk in the Gastrointestinal Hamartomatous Polyposis Syndromes: Recommendations From the US Multi-Society Task Force on Colorectal Cancer

The gastrointestinal hamartomatous polyposis syndromes are rare, autosomal dominant disorders associated with an increased risk of benign and malignant intestinal and extraintestinal tumors. They include Peutz-Jeghers syndrome, juvenile polyposis syndrome, the PTEN hamartoma tumor syndrome (including Cowden's syndrome and Bannayan-Riley-Ruvalcaba syndrome), and hereditary mixed polyposis syndrome. Diagnoses are based on clinical criteria and, in some cases, confirmed by demonstrating the presence of a germline pathogenic variant. The best understood hamartomatous polyposis syndrome is Peutz-Jeghers syndrome, caused by germline pathogenic variants in the STK11 gene. The management is focused on prevention of bleeding and mechanical obstruction of the small bowel by polyps and surveillance of organs at increased risk for cancer. Juvenile polyposis syndrome is caused by a germline pathogenic variant in either the SMAD4 or BMPR1A genes, with differing clinical courses. Patients with SMAD4 pathogenic variants may have massive gastric polyposis, which can result in gastrointestinal bleeding and/or protein-losing gastropathy. Patients with SMAD4 mutations usually have the simultaneous occurrence of hereditary hemorrhagic telangiectasia (juvenile polyposis syndrome-hereditary hemorrhagic telangiectasia overlap syndrome) that can result in epistaxis, gastrointestinal bleeding from mucocutaneous telangiectasias, and arteriovenous malformations. Germline pathogenic variants in the PTEN gene cause overlapping clinical phenotypes (known as the PTEN hamartoma tumor syndromes), including Cowden's syndrome and related disorders that are associated with an increased risk of gastrointestinal and colonic polyposis, colon cancer, and other extraintestinal manifestations and cancers. Due to the relative rarity of the hamartomatous polyposis syndromes, recommendations for management are based on few studies. This U.S Multi-Society Task Force on Colorectal Cancer consensus statement summarizes the clinical features, assesses the current literature, and provides guidance for diagnosis, assessment, and management of patients with the hamartomatous polyposis syndromes, with a focus on endoscopic management.

Diagnosis and management of cancer risk in the gastrointestinal hamartomatous polyposis syndromes: recommendations from the U.S. Multi-Society Task Force on Colorectal Cancer

The gastrointestinal hamartomatous polyposis syndromes are rare, autosomal dominant disorders associated with an increased risk of benign and malignant intestinal and extraintestinal tumors. They include Peutz-Jeghers syndrome, juvenile polyposis syndrome, the PTEN hamartoma tumor syndrome (including Cowden's syndrome and Bannayan-Riley-Ruvalcaba syndrome), and hereditary mixed polyposis syndrome. Diagnoses are based on clinical criteria and, in some cases, confirmed by demonstrating the presence of a germline pathogenic variant. The best understood hamartomatous polyposis syndrome is Peutz-Jeghers syndrome, caused by germline pathogenic variants in the STK11 gene. The management is focused on prevention of bleeding and mechanical obstruction of the small bowel by polyps and surveillance of organs at increased risk for cancer. Juvenile polyposis syndrome is caused by a germline pathogenic variant in either the SMAD4 or BMPR1A genes, with differing clinical courses. Patients with SMAD4 pathogenic variants may have massive gastric polyposis, which can result in gastrointestinal bleeding and/or protein-losing gastropathy. Patients with SMAD4 mutations usually have the simultaneous occurrence of hereditary hemorrhagic telangiectasia (juvenile polyposis syndrome-hereditary hemorrhagic telangiectasia overlap syndrome) that can result in epistaxis, gastrointestinal bleeding from mucocutaneous telangiectasias, and arteriovenous malformations. Germline pathogenic variants in the PTEN gene cause overlapping clinical phenotypes (known as the PTEN hamartoma tumor syndromes), including Cowden's syndrome and related disorders that are associated with an increased risk of gastrointestinal and colonic polyposis, colon cancer, and other extraintestinal manifestations and cancers. Due to the relative rarity of the hamartomatous polyposis syndromes, recommendations for management are based on few studies. This U.S. Multi-Society Task Force on Colorectal Cancer consensus statement summarizes the clinical features, assesses the current literature, and provides guidance for diagnosis, assessment, and management of patients with the hamartomatous polyposis syndromes, with a focus on endoscopic management.

Diagnosis and Management of Cancer Risk in the Gastrointestinal Hamartomatous Polyposis Syndromes: Recommendations From the US Multi-Society Task Force on Colorectal Cancer

The gastrointestinal hamartomatous polyposis syndromes are rare, autosomal dominant disorders associated with an increased risk of benign and malignant intestinal and extraintestinal tumors. They include Peutz-Jeghers syndrome, juvenile polyposis syndrome, the PTEN hamartoma tumor syndrome (including Cowden's syndrome and Bannayan-Riley-Ruvalcaba syndrome), and hereditary mixed polyposis syndrome. Diagnoses are based on clinical criteria and, in some cases, confirmed by demonstrating the presence of a germline pathogenic variant. The best understood hamartomatous polyposis syndrome is Peutz-Jeghers syndrome, caused by germline pathogenic variants in the STK11 gene. The management is focused on prevention of bleeding and mechanical obstruction of the small bowel by polyps and surveillance of organs at increased risk for cancer. Juvenile polyposis syndrome is caused by a germline pathogenic variant in either the SMAD4 or BMPR1A genes, with differing clinical courses. Patients with SMAD4 pathogenic variants may have massive gastric polyposis, which can result in gastrointestinal bleeding and/or protein-losing gastropathy. Patients with SMAD4 mutations usually have the simultaneous occurrence of hereditary hemorrhagic telangiectasia (juvenile polyposis syndrome-hereditary hemorrhagic telangiectasia overlap syndrome) that can result in epistaxis, gastrointestinal bleeding from mucocutaneous telangiectasias, and arteriovenous malformations. Germline pathogenic variants in the PTEN gene cause overlapping clinical phenotypes (known as the PTEN hamartoma tumor syndromes), including Cowden's syndrome and related disorders that are associated with an increased risk of gastrointestinal and colonic polyposis, colon cancer, and other extraintestinal manifestations and cancers. Due to the relative rarity of the hamartomatous polyposis syndromes, recommendations for management are based on few studies. This US Multi-Society Task Force on Colorectal Cancer consensus statement summarizes the clinical features, assesses the current literature, and provides guidance for diagnosis, assessment, and management of patients with the hamartomatous polyposis syndromes, with a focus on endoscopic management.

LKB1 Is Physiologically Required for Sleep from Drosophila melanogaster to the Mus musculus

Liver Kinase B1 (LKB1) is known as a master kinase for 14 kinases related to the adenosine monophosphate (AMP)-activated protein kinase (AMPK). Two of them salt inducible kinase 3 (SIK3) and AMPKα have previously been implicated in sleep regulation. We generated loss-of-function (LOF) mutants for Lkb1 in both Drosophila and mice. Sleep, but not circadian rhythms, was reduced in Lkb1-mutant flies and in flies with neuronal deletion of Lkb1. Genetic interactions between Lkb1 and Threonine to Alanine mutation at residue 184 of AMPK in Drosophila sleep or those between Lkb1 and Threonine to Glutamic Acid mutation at residue 196 of SIK3 in Drosophila viability have been observed. Sleep was reduced in mice after virally mediated reduction of Lkb1 in the brain. Electroencephalography (EEG) analysis showed that non-rapid eye movement (NREM) sleep and sleep need were both reduced in Lkb1-mutant mice. These results indicate that LKB1 plays a physiological role in sleep regulation conserved from flies to mice.

Sex-Cord Tumor with Annular Tubules with Unusual Morphology in an Infant with Peutz-Jeghers Syndrome

Background Peutz-Jeghers syndrome (PJS) is characterized by hamartomatous gastrointestinal polyposis, mucocutaneous pigmentation and cancer predisposition. The clinical features of PJS manifest in first two decades of life; however, neonatal presentation is uncommon. Case report: We present a five day old girl with PJS that presented with obstructive hamartomatous polyps in the sigmoid colon. At colostomy closure at six months, an incidental ovarian sex-cord tumor with annular tubules (SCTAT) was detected. It showed predominantly a solid pattern with limited tubule formation and was composed of lipid-rich cells. She had no hormonal symptoms. Conclusion: SCTAT can occur as young as six months of age in PJS, and may show histologic overlap with lipid-rich Sertoli cell tumors.

Nonmalignant Features Associated with Inherited Colorectal Cancer Syndromes-Clues for Diagnosis

Simple Summary

Familiarity with nonmalignant features and comorbidities of cancer predisposition syndromes may raise awareness and assist clinicians in the diagnosis and interpretation of molecular test results. Genetic predisposition to colorectal cancer (CRC) should be suspected mainly in young patients, in patients with significant family histories, multiple polyps, mismatch repair-deficient tumors, and in association with malignant or nonmalignant comorbidities. The aim of this review is to describe the main nonmalignant comorbidities associated with selected CRC predisposition syndromes that may serve as valuable diagnostic clues for clinicians and genetic professionals.

Abstract

Genetic diagnosis of affected individuals and predictive testing of their at-risk relatives, combined with intensive cancer surveillance, has an enormous cancer-preventive potential in these families. A lack of awareness may be part of the reason why the underlying germline cause remains unexplained in a large proportion of patients with CRC. Various extracolonic features, mainly dermatologic, ophthalmic, dental, endocrine, vascular, and reproductive manifestations occur in many of the cancer predisposition syndromes associated with CRC and polyposis. Some are mediated via the WNT, TGF-β, or mTOR pathways. However the pathogenesis of most features is still obscure. Here we review the extracolonic features of the main syndromes, the existing information regarding their prevalence, and the pathways involved in their pathogenesis. This knowledge could be useful for care managers from different professional disciplines, and used to raise awareness, enable diagnosis, and assist in the process of genetic testing and interpretation.

Juvenile polyposis diagnosed with an integrated histological, immunohistochemical and molecular approach identifying new SMAD4 pathogenic variants

Juvenile polyposis (JP) is a rare familial syndrome characterized by the development of numerous hamartomatous polyps of the gastrointestinal tract and by an increased risk of developing gastrointestinal cancers. It follows a pattern of autosomal dominant inheritance and is associated with germline variants of SMAD4 or BMPR1A genes. Differential diagnosis may be difficult based on histology alone, due to morphological similarities to other familial syndromes. Here we report a case of familial JP diagnosed in a 50-years woman with a familial history positive for gastrointestinal cancers and other tumor types. The patient presented with severe iron deficiency anemia and showed numerous polyps in the stomach and jejunum according to endoscopy and imaging. She underwent an intra-gastric laparoscopic removal of the major gastric polyp, followed by jejunal exploration and resection of a segment with multiple neoformations. Histological examination revealed the presence of hamartomatous polyposis. Gastric and intestinal samples were analyzed with next-generation sequencing. Molecular analysis showed that the patient harbored a germline splicing site variant of SMAD4, c.1139 + 3A > G, which was complemented by different somatic variants of the same gene in the different polyps. Immunohistochemistry for SMAD4 confirmed loss of protein expression in the polyps, with regular expression in normal cells. cDNA sequencing further confirmed the findings. We thus definitively diagnosed the woman as having JP thanks to an integrated approach based on histology, immunohistochemistry and molecular analysis. The identified variants, all previously reported as variants of unknown significance, were classified as pathogenic as they complemented each other leading to SMAD4 loss.

Appendiceal carcinoid in a pediatric patient with Peutz-Jeghers syndrome: A case report and comprehensive literature review

RATIONALE

Peutz-Jeghers syndrome (PJS), a rare autosomal dominant disorder, is characterized by mucocutaneous pigmentations, hamartomatous polyps in the gastrointestinal tract, and a high risk of developing various malignancies. To the best of our knowledge, only 1 case of appendiceal carcinoid associated with PJS has been previously reported in the pediatric population.

PATIENT CONCERNS

We report a 7-year-old girl who was admitted for severe, intermittent abdominal pain and cramps, nausea, and vomiting. Multiple brown melanotic macules on the lips, buccal mucosa, and the tongue were noted.

DIAGNOSIS

A plain abdominal X-ray in a standing position revealed dilated intestinal loops with multiple air-fluid levels. A computed tomography scan of the abdomen showing a "coffee bean" appearance of the jejunal loop with a transition point to the duodenal loop. Axial-contrast-enhanced computed tomography scan of the abdomen showing dilated jejunum loops, filled with fluid with the swirled appearance of mesentery typical for volvulus. The diagnosis of PJS was based on clinical findings along with the histopathologic confirmation of the hamartomatous polyps.

INTERVENTIONS

An emergency laparotomy was performed, revealing a jejunojejunal intussusception starting 40 cm from the duodenojejunal flexure. Jejunotomy revealed that a lead-point intussusception was a necrotic hamartomatous polyp. After resecting the involved jejunal necrotic segment, including the polyp, end-to-end jejuno-jejunal anastomosis was performed. Further exploration revealed the presence of a jejunal mass 80 cm from the duodenojejunal flexure identified as another hamartomatous pedunculated polyp. The polyp was resected, and the enterotomy was then closed transversely. The grossly normal appendix was also removed.

OUTCOMES

Clinical findings along with the histopathologically confirmed hamartomatous polyps were consistent with PJS. An appendiceal carcinoid (well-differentiated neuroendocrine tumor, European Neuroendocrine Tumor Society stage pT2) was incidentally detected during histological examination of the appendix. The patient and parents were counseled accordingly, focusing on active surveillance and control of symptoms. Two additional hamartomatous polyps (gastric and jejunal) were detected endoscopically and resected in the fourth postoperative week. A regular, 1-year follow-up and surveillance revealed no complications or recurrences.

LESSONS

Unusual neoplasms can occasionally be encountered in well-defined syndromes such as PJS. Therefore, active follow-up and surveillance are mandatory for all patients with PJS.

The Management of Peutz-Jeghers Syndrome: European Hereditary Tumour Group (EHTG) Guideline

The scientific data to guide the management of Peutz–Jeghers syndrome (PJS) are sparse. The available evidence has been reviewed and discussed by diverse medical specialists in the field of PJS to update the previous guideline from 2010 and formulate a revised practical guideline for colleagues managing PJS patients. Methods: Literature searches were performed using MEDLINE, Embase, and Cochrane. Evidence levels and recommendation strengths were assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE). A Delphi process was followed, with consensus being reached when ≥80% of the voting guideline committee members agreed. Recommendations and statements: The only recent guidelines available were for gastrointestinal and pancreatic management. These were reviewed and endorsed after confirming that no more recent relevant papers had been published. Literature searches were performed for additional questions and yielded a variable number of relevant papers depending on the subject addressed. Additional recommendations and statements were formulated. Conclusions: A decade on, the evidence base for recommendations remains poor, and collaborative studies are required to provide better data about this rare condition. Within these restrictions, multisystem, clinical management recommendations for PJS have been formulated.

Ovarian sex cord-stromal tumors: an update on clinical features, molecular changes, and management

Sex cord stromal-tumors are rare tumors of the ovary that include numerous tumor subtypes of variable histological features and biological behavior. Surgery is the main therapeutic modality for the management of these tumors, while chemotherapy and hormonal therapy may be used in some patients with progressive and recurrent tumors. Several studies investigated molecular changes in the different tumor types. Understanding molecular changes underlying the development and progression of sex cord-stromal tumors provides valuable information for diagnostic and prognostic biomarkers and potential therapeutic targets for these tumors. In this review, we provide an update on the clinical presentation, molecular changes, and management of sex cord-stromal tumors.

Molecular Features and Clinical Management of Hereditary Gynecological Cancers

Hereditary gynecological cancers are caused by several inherited genes. Tumors that arise in the female reproductive system, such as ovaries and the uterus, overlap with hereditary cancers. Several hereditary cancer-related genes are important because they might lead to therapeutic targets. Treatment of hereditary cancers should be updated in line with the advent of various new methods of evaluation. Next-generation sequencing has led to rapid, economical genetic analyses that have prompted a concomitant and significant paradigm shift with respect to hereditary cancers. Molecular tumor profiling is an epochal method for determining therapeutic targets. Clinical treatment strategies are now being designed based on biomarkers based on tumor profiling. Furthermore, the National Comprehensive Cancer Network (NCCN) guidelines significantly changed the genetic testing process in 2020 to initially consider multi-gene panel (MGP) evaluation. Here, we reviewed the molecular features and clinical management of hereditary gynecological malignancies, such as hereditary breast and ovarian cancer (HBOC), and Lynch, Li–Fraumeni, Cowden, and Peutz–Jeghers syndromes. We also reviewed cancer-susceptible genes revealed by MGP tests.

Novel germline STK11 variants and breast cancer phenotype identified in an Indian cohort of Peutz-Jeghers syndrome

Peutz-Jeghers syndrome (PJS) caused by germline STK11 variants is a rare autosomal dominant cancer predisposition syndrome characterized by multiple gastrointestinal (GI) hamartomatous polyps, mucocutaneous pigmentation and a high inherited risk of developing GI, breast and other cancers. Despite GI and breast being the two most common PJS-associated cancer sites, the immunohistochemical (IHC) and molecular features of these tumors in carriers of STK11 variant is not known. Detailed phenotyping including tumor IHC and its correlation with comprehensive STK11 genotyping by full gene sequencing followed by large genomic rearrangement analysis was performed in an Indian PJS cohort. A total of 4 distinct STK11 pathogenic or likely pathogenic variants were identified in 10 PJS cases from 7 of the 19 families tested-in 4/5 classical PJS families and 3/14 suspected PJS families. The pathogenic STK11 variant identified was novel in 3/7 families. In addition, four distinct, likely benign variants identified in seven families were also novel. All of the four breast cancer cases in families with STK11 pathogenic variant were estrogen receptor (ER)-positive and Her2-negative. Several novel STK11 variants identified in this Indian PJS cohort highlight the need to study PJS in different populations across the world. This is the first report showing ER positivity in breast cancer in carriers of STK11 variants and needs confirmation in a larger pooled cohort of PJS associated breast cancers. This could help establish the role of chemoprevention or prophylactic oophorectomy in female carriers of STK11 pathogenic variants.

Identifying breast cancer susceptibility genes - a review of the genetic background in familial breast cancer

INTRODUCTION

Heritage is the most important risk factor for breast cancer. About 15-20% of breast cancer is familial, referring to affected women who have one or more first- or second-degree relatives with the disease. The heritable component in these families is substantial, especially in families with aggregation of breast cancer with low age at onset. Identifying breast cancer susceptibility genes: Since the discovery of the highly penetrant autosomal dominant susceptibility genes BRCA1 and BRCA2 in the 1990s, several more breast cancer genes that confer a moderate to high risk of breast cancer have been identified. Furthermore, during the last decade, advances in genomic technologies have led to large scale genotyping in genome-wide association studies that have identified a considerable amount of common low penetrance loci. In total, the high risk genes, BRCA1, BRCA2, TP53, STK11, CD1 and PTEN account for approximately 20% of the familial risk. Moderate risk variants account for up to 5% of the inherited familial risk. The more than 180 identified low-risk loci explain 18% of the familial risk. Altogether more than half of the genetic background in familial breast cancer remains unclear. Other genes and low risk loci that explain a part the remaining fraction will probably be identified. Clinical aspects and future perspectives: Definitive clinical recommendations can be drawn only for carriers of germline variants in a limited number of high and moderate risk genes for which an association with breast cancer has been established. Future progress in evaluating previously identified breast cancer candidate variants and low risk loci as well as exploring new ones can play an important role in improving individual risk prediction in familial breast cancer.

Mystery behind labial and oral melanotic macules: Clinical, dermoscopic and pathological aspects of Laugier-Hunziker syndrome

Labial and oral melanotic macules are commonly encountered in a broad range of conditions ranging from physiologic pigmentation to a sign of an underlying life-threatening disease. Although Laugier-Hunziker syndrome (LHS) shares some features of labial and oral pigmentation with a variety of conditions, it is a benign and acquired condition, frequently associated with longitudinal melanonychia. Herein, the demographic, clinical, dermoscopic, and pathological aspects of LHS were reviewed comprehensively. The important differential diagnoses of mucocutaneous and nail pigmentation are provided. An accurate diagnosis is crucial to design a reasonable medical strategy, including management options, malignant transformation surveillance, and psychological support. It is important that clinicians conduct long-term follow-up and surveillance due to the potential risks of malignant transformation and local severe complications in some conditions.

Update on small bowel surveillance in hereditary colorectal cancer syndromes

Despite its rarity in the general population, small bowel adenocarcinoma risk is increased in individuals with hereditary colorectal cancer syndromes (HCCS). In the last decade, the advent of capsule endoscopy and device-assisted balloon enteroscopy procedures in patients with HCCS have allowed to investigate the whole small bowel, increasing the diagnostic yield of small bowel tumor. Nonetheless, there is a significant variability in the international guideline recommendations. The aim of this review is to provide an update on surveillance of small bowel in HCCS and to identify the key points for the clinical management of these patients.

Metachronous triple cancer associated with Peutz-Jeghers syndrome treated with curative surgery: a case report

Background

Peutz–Jeghers syndrome (PJS) is an autosomal dominant disorder characterized by mucocutaneous pigmentation and hamartomatous gastrointestinal polyposis. It is well known that individuals with PJS are at an increased risk of cancer in a variety of organs.

Case presentation

Here, we present a patient with PJS who achieved long-term survival by undergoing repeat curative surgery for metachronous triple cancer. Her medical history included hilar cholangiocarcinoma and cervical carcinoma; curative surgery was performed for both conditions. On annual follow-up, the level of carcinoembryonic antigen was elevated at 6.9 ng/ml. Enhanced computed tomography revealed a cystic tumor consisting of mural nodules at the pancreatic head; the maximal diameter was 15 mm. Magnetic resonance imaging clearly demonstrated the tumor with low intensity on T1-weighted images and high intensity on T2-weighted images. Endoscopic ultrasound sonography showed a high echoic tumor at the pancreatic head, which was confirmed as adenocarcinoma by fine-needle aspiration biopsy. The preoperative diagnosis was intraductal papillary mucinous carcinoma (IPMC; T1N0M0, stage IA). Subtotal stomach-preserving pancreaticoduodenectomy was performed and the final diagnosis was IPMC, stage 0 (TisN0M0).

Conclusions

Aggressive surgery for metachronous triple cancer resulted in good long-term prognosis. Continuous and systematic follow-up would allow the detection of malignancy at an early stage and make treatment with curative surgery possible.

Non-familial juvenile polyposis of the stomach with gastric cancers: a case report

Background

Juvenile polyposis is an autosomal dominant inherited disease characterized by the development of numerous hamartomatous and nonneoplastic polyps of the gastrointestinal tract. Juvenile polyposis has also recently been reported as a predisposition for gastrointestinal cancer.

Case presentation

A 63-year-old man underwent esophagogastroduodenoscopy because of anemia and hypoalbuminemia during a follow-up for gastric polyposis, which showed multiple reddish polyps and two elevated lesions in the stomach. The elevated lesions were diagnosed as well-differentiated adenocarcinomas by biopsy. He had no specific physical findings or family history. Computed tomography showed gastric wall thickening without lymphadenopathy or distant metastasis. Colonoscopy showed an adenoma in the transverse colon. He underwent laparoscopy-assisted total gastrectomy with Roux-en-Y esophagojejunostomy. The resected specimen revealed numerous variously sized non-pedunculated polyps throughout the stomach, diagnosed histopathologically as hamartomatous polyps. The two elevated lesions were diagnosed as a well-differentiated adenocarcinoma restricted to the mucosa and a well-to-poorly differentiated adenocarcinoma invading the submucosa with prominent lymphatic permeation, respectively. Genetic analysis failed to identify any germline mutations in the genes usually associated with juvenile polyposis, including SMAD4 and BMPR1A. However, based on the few characteristic physical findings and histopathological features, the final diagnosis was juvenile polyposis restricted to the stomach.

Conclusions

This patient represented a rare case of non-familial juvenile polyposis of the stomach with gastric cancers. Juvenile polyposis has malignant potential, and patients should therefore be carefully followed up. Surgical treatment, particularly total gastrectomy, is recommended as a standard treatment in patients with juvenile polyposis of the stomach with gastric cancer.

Familial Pancreatic Cancer and the Future of Directed Screening

Pancreatic cancer (PC) is the third most common cause of cancer-related death in the United States and the 12th most common worldwide. Mortality is high, largely due to late stage of presentation and suboptimal treatment regimens. Approximately 10% of PC cases have a familial basis. The major genetic defect has yet to be identified but may be inherited by an autosomal dominant pattern with reduced penetrance. Several known hereditary syndromes or genes are associated with an increased risk of developing PC and account for approximately 2% of PCs. These syndromes include the hereditary breast-ovarian cancer syndrome, Peutz-Jeghers syndrome, familial atypical multiple mole melanoma, Lynch syndrome, familial polyposis, ataxia-telangiectasia, and hereditary pancreatitis. Appropriate screening using methods such as biomarkers or imaging, with endoscopic ultrasound and magnetic resonance imaging, may assist in the early detection of neoplastic lesions in the high-risk population. If these lesions are detected and treated before the development of invasive carcinoma, PC disease morbidity and mortality may be improved. This review will focus on familial PC and other hereditary syndromes implicated in the increased risk of PC; it will also highlight current screening methods and the future of new screening modalities.

Current Approaches to Pediatric Polyposis Syndromes

Colorectal adenomatous polyposis syndromes encompass a diverse group of disorders with varying modes of inheritance and penetrance. Children may present with overt disease or within screening programs for families at high risk. We provide an overview of the array of pediatric polyposis syndromes, current screening recommendations, and surgical indications and technical considerations. Optimal disease management for these pediatric patients is still evolving and has implications for screening, surveillance, pediatric surgical management, and transition of care gastroenterologic neoplasia physicians and surgeons.

Genetic analysis and clinical description of Greek patients with Peutz-Jeghers syndrome: Creation of a National Registry

Peutz-Jeghers syndrome (PJS) is a rare autosomal dominant disorder caused by germline mutations in the STK11 tumor suppressor gene. PJS patients face a cumulative cancer risk as high as 93% for all sites combined. The present study reports the spectrum of STK11 mutations in eight families with clinical diagnosis of PJS, summarizes the clinical characteristics of sixteen mutation carriers and launches a National Registry for PJS in Greece. STK11 loss-of-function (LoF) mutations were detected in 87.5% of index patients. Carriers presented with their first manifestation at a median age of 24.9 years, while early-onset breast cancer was the most frequent malignancy observed, highlighting the need for breast surveillance. Out of the deleterious STK11 mutations identified, two were novel: c.375_376delGT and c.676_679dupAACG, with 57.2% of these potentially occurring de novo. Using all available clinical and genetic data, the National Registry for Greek PJS was established in an attempt to better characterize the syndrome and raise awareness among patients and clinicians (available at https://www.peutzjeghersgreece.org). This is the first comprehensive genetic analysis and clinical characterization of Greek PJS patients, where a high incidence of breast cancer was observed and the first attempt to centralize all data in a National Registry.

Cancer risk in patients with Peutz-Jeghers syndrome: A retrospective cohort study of 336 cases

Peutz-Jeghers syndrome is a rare autosomal dominant inherited disorder characterized by mucocutaneous pigmentation and hamartomatous gastrointestinal polyposis. A growing body of evidence has shown that Peutz-Jeghers syndrome could cause an increased risk of various cancers, yet the range of cancer risk estimates was wide among different studies. In this retrospective cohort study, 336 patients with Peutz-Jeghers syndrome in China were enrolled. The clinical characteristics, cancer spectrum, relative cancer risks, and cumulative cancer risks were analyzed. In total, 52 patients were diagnosed of cancer in the follow-up period, at a median age of 41 years (range: 21-67). The relative risk for cancer in Peutz-Jeghers syndrome patients was 63.858 (confidence interval: 47.514-85.823), and the cumulative cancer risk at the age of 60 years was 55%. Colorectal cancer was the most common cancer for Peutz-Jeghers syndrome patients (relative risk: 237.918, confidence interval: 154.417-366.572) and the cumulative cancer risk at the age of 60 years was 28%. There was a statistically significant difference in the cumulative cancer risk between patients with family history and those without family history, as well as between patients living in rural area and those living in urban areas ( p < 0.05), while no significant effects of gender and intussusception history on the cumulative cancer risk was found ( p > 0.05). Hopefully, our study may contribute to the management of this rare disorder and establishment of related surveillance projects, especially in China.

An Overview of Autosomal Dominant Tumour Syndromes with Prominent Features in the Oral and Maxillofacial Region

Several autosomal dominant inherited tumour syndromes demonstrate prominent features in the oral and maxillofacial region. Although multiple organ systems are frequently involved, the target organs more frequently affected are the skin (nevoid basal cell carcinoma syndrome, Brooke-Spiegler syndrome, Birt-Hogg-Dube syndrome and Muir-Torre syndrome), gastrointestinal tract (Peutz-Jegher syndrome and Gardner syndrome) or endocrine system (multiple endocrine neoplasia type 2b and hyperparathyroidism-jaw tumour syndrome). In some syndromes, the disease is multisystem with skin index lesions presenting in the head and neck (Cowden syndrome and tuberous sclerosis complex). The pertinent features of these syndromes are reviewed with a systems-based approach, emphasising their clinical impact and diagnosis.

Surveillance of patients with hereditary gastrointestinal cancer syndromes

Gastrointestinal cancers are among the most frequent tumors. Although most cases are sporadic, up to 5-6% develops in the context of gastrointestinal hereditary syndromes. These entities have specific characteristics and often a germline mutation identified, thus allowing performing genetic counseling. This review summarizes the most common gastrointestinal hereditary syndromes, focusing on the surveillance recommendations.

Genetic Screening and Analysis of LKB1 Gene in Chinese Patients with Peutz-Jeghers Syndrome

BACKGROUND Peutz-Jeghers syndrome (PJS) is an autosomal dominant genetic disease. It severely decreases patient quality of life and leads elevated cancer risk. Germline mutation of LKB1 is the leading cause of familial PJS. MATERIAL AND METHODS To characterize the germline mutation of LKB1 gene in Chinese familial and sporadic PJS patients, 14 PJS families, 5 sporadic PJS patients, and 250 healthy adults were collected and genomic DNAs of peripheral blood were extracted. Mutation screenings of LKB1 were performed using MLPA (multiplex ligation-dependent probe amplification), PCR, direct sequencing, and PCR-DHPLC (denaturing high-performance liquid chromatography). RESULTS A total of 12 kinds of germline mutations were found in 9 familial PJS patients, most of which were point mutations (7/12); 4 large deletions of LKB1 were also observed. Of the 12 mutations, 7 were pathogenic (2 were de novo), 4 were just polymorphisms, and 1 was indefinitely pathogenic. No pathogenic mutation in exons of the LKB1 gene was detected in the 5 sporadic PJS patients. The mutation detection rate for the LKB1 gene was 85.7% in our Chinese familial PJS and 63.2% in all Chinese PJS patients. Eight familial PJS patients were identified with pathogenic germline mutations in 14 unrelated families (57.1%). Further methylation detection and analysis showed promoter methylation in carcinomatous polyps. CONCLUSIONS LKB1 gene germline mutation with pathogenic effect is a common cause of familial PJS in Chinese patients; however, it is not the only molecular pathogen of PJS. Methylation in the LKB1 gene promoter region may cause carcinomatous change in intestinal polyps.

Unusual Sertoli Cell Tumor Associated With Sex Cord Tumor With Annular Tubules in Peutz-Jeghers Syndrome

We report the case of an 11-year-old girl with Peutz-Jeghers syndrome and a unilateral ovarian tumor most consistent with Sertoli cell tumor associated with sex cord tumor with annular tubules. The ovary was replaced by a lobular, solid, yellow tumor. Microscopic examination showed 2 components that focally merged. The first was composed of uniform, cytologically bland cells arranged mostly in diffuse sheets and focally in tubules. The second showed typical sex cord tumor with annular tubules with extensive calcification. The predominant component of the tumor clearly fell in the sex cord category and most closely resembled Sertoli cell tumor. This case adds to the limited information on ovarian sex cord tumors, other than typical sex cord tumor with annular tubules, arising in association with Peutz-Jeghers syndrome, a topic reviewed herein.

Wireless capsule endoscopy in adolescents with familial adenomatous polyposis

Aims and background

Guidelines for surveillance in patients with familial adenomatous polyposis (FAP) recommend mutation carriers to undergo periodic colorectal examination starting in the early teens. Performing colonoscopy in children may lead to complications. Wireless capsule endoscopy (WCE) has been introduced recently to evaluate both the upper and lower gastrointestinal tract, and seems suitable as a first screening examination for adolescents. The aim of this study was to evaluate the pros and cons of WCE.

Methods

This was a retrospective review of a single institution database of adolescent patients with FAP identified through the Hereditary Colorectal Tumor Registry between 2007 and 2013. The main outcomes were identification of upper and lower gastrointestinal tract polyps, tolerance of the examination, and number and size of polyps.

Results

Of 46 adolescent patients with FAP, 14 (30.4%) patients carrying adenomatous polyposis coli gene ( APC) mutation, 6 male and 8 female, age (median, range) 12 (10-17) years, body mass index 19 (13-24), underwent WCE as first screening examination. The examination was completed in 13 patients (93.3%). Wireless capsule endoscopy identified the duodenal papilla in 4 patients and colonic and rectal polyps in all 13 patients. In 7 patients, fewer than 25 polyps were identified. No complications were recorded related to the use of the video capsule.

Conclusions

Wireless capsule endoscopy is feasible and well-tolerated as a first screening examination in adolescent patients. It cannot be used as alternative to the colonoscopy, but could improve compliance with colonoscopy, and increase early adherence to a surveillance program.

Tumour spectrum in non-BRCA hereditary breast cancer families in Sweden

BACKGROUND

Approximately 30 % of all breast cancer is at least partly attributed to hereditary factors. Familial breast cancer is often inherited in the context of cancer syndromes. The most commonly mutated genes are BRCA1 and BRCA2 in hereditary breast and ovarian cancer syndrome. The genetic background in families with hereditary breast cancer without predisposing germ line mutations in BRCA1 and BRCA2 (non-BRCA families) is still to a large extent unclear even though progress has been made. The aim of this study was to compare cancer proportions in familial non-BRCA hereditary breast cancer compared to the general population in search of putative new breast cancer syndromes.

METHODS

Pedigrees from 334 non-BRCA hereditary breast cancer families in the county of Stockholm, Sweden, were investigated and the distribution of cancer diagnoses other than breast cancer was compared with the distribution of cancer diagnoses in the general Swedish population in two reference years, 1970 and 2010. A cancer diagnosis was regarded as overrepresented in the non-BRCA families if the confidence interval was above both population reference values.

RESULTS

We found that endometrial cancer was overrepresented in the non-BRCA families with a 6.36 % proportion (CI 4.67-8.2) compared to the proportion in the general population in the reference years 1970 (3.07 %) and 2010 (2.64 %). Moreover tumours of the ovary, liver, pancreas and prostate were overrepresented.

CONCLUSION

In conclusion, we found an overrepresentation of endometrial cancer in our cohort of hereditary non-BRCA families. Our result supports previous inconsistent reports of a putative breast and endometrial cancer syndrome. An association has been suggested in studies of families with several cases of breast cancer in close relatives or bilateral breast cancer. To clarify this issue we suggest further studies on a breast and endometrial cancer syndrome in cohorts with a strong pattern of hereditary breast cancer. Identifying new breast cancer syndromes is of importance to improve genetic counselling for women at risk and a first step towards detection of new susceptibility genes.

Q-switched Nd:YAG laser treatment for labial lentigines associated with Peutz-Jeghers syndrome

BACKGROUND AND OBJECTIVE

Labial lentigines associated with Peutz-Jeghers syndrome are cosmetically disfiguring and distressful. Although multiple treatment modalities including Q-switched ruby laser and Q-switched alexandrite laser have been proposed, experience with Q-switched Nd:YAG laser has been lacking. This study aimed to retrospectively evaluate the efficacy and safety of Q-switched Nd:YAG laser (532 nm) for labial lentigines in Peutz-Jeghers syndrome.

PATIENTS AND METHODS

Demographic and clinical data of 11 patients diagnosed with Peutz-Jeghers syndrome were analyzed. A quartile grading system was used. All patients were treated with a Q-switched Nd:YAG laser system with the following parameters: wavelength 532 nm; spot size 3 mm; pulse duration 5-20 ns; fluence 1.8-2.2 J/cm(2) .

RESULTS

After two to six (mean 3.6) treatment sessions, an average grade of 3.73 was achieved. Eight patients (72.7 %) showed an excellent response with more than 75 % lesion clearance. Three patients (27.3 %) showed a good response. Repeated treatments led to improved clearance of labial lentigines. Age, gender, and Fitzpatrick skin type were not statistically associated with efficacy grades after the first treatment session. Neither recurrence in treated areas nor significant complications were observed.

CONCLUSIONS

Q-switched Nd:YAG laser provides an effective and safe treatment option for labial lentigines associated with Peutz-Jeghers syndrome.

[Hereditary predisposition to cancers of the digestive tract, breast, gynecological and gonadal: focus on the Peutz-Jeghers]

Peutz-Jeghers syndrome (PJS) is a rare autosomal dominant disease due to mutations in the tumor suppressor gene STK11. PJS is characterized by periorificial hyperpigmented macules (lentiginosis) and hamartomatous polyposis. Polyps can be located anywhere in the gastrointestinal tract, but are preferably observed in the small bowel (70-90%), the colon (50%) and the stomach (25%). They tend to be cancerous in a particular sequence hamartoma-dysplasia-cancer. The diagnosis is often made in the first or second decade following the appearance of lentigines or upon the occurrence of complications due to polyps (obstruction, intussusception, occult bleeding responsible for anemia). Furthermore PJS is associated with a significant increase in cancer risk (relative risk of 89% over the life according to the most recent series). Digestive cancers are the more frequent with cumulative incidences of 55% for gastro-intestinal cancer (39% for colorectal cancer, 13% for small bowel cancer and between 11 and 36% for pancreatic cancer, respectively). There is also an increased risk of non digestive cancers. In particular the risk of breast cancer is similar to that of patients carrying deleterious BRCA1 or BRCA2 mutations (cumulative incidence of 45%). Gynecological and gonadal tumors are frequent as well and can be more (adenoma malignum) or less aggressive (ovarian sex cord tumors with annular tubules and testicular tumors with calcified Sertoli cells). Finally the frequency of lung cancer is moderately increased. Recommendations for screening and management based on retrospective series in the literature have led to various strategies. The aim of this paper is to summarize the clinical and molecular diagnostic criteria of PJS as well as recommendations on screening strategies, management and monitoring.

LKB1 preserves genome integrity by stimulating BRCA1 expression

Serine/threonine kinase 11 (STK11, also known as LKB1) functions as a tumor suppressor in many human cancers. However, paradoxically loss of LKB1 in mouse embryonic fibroblast results in resistance to oncogene-induced transformation. Therefore, it is unclear why loss of LKB1 leads to increased predisposition to develop a wide variety of cancers. Here, we show that LKB1 protects cells from genotoxic stress. Cells lacking LKB1 display increased sensitivity to irradiation, accumulates more DNA double-strand breaks, display defective homology-directed DNA repair (HDR) and exhibit increased mutation rate, compared with that of LKB1-expressing cells. Conversely, the ectopic expression of LKB1 in cells lacking LKB1 protects them against genotoxic stress-induced DNA damage and prevents the accumulation of mutations. We find that LKB1 post-transcriptionally stimulates HDR gene BRCA1 expression by inhibiting the cytoplasmic localization of the RNA-binding protein, HU antigen R, in an AMP kinase-dependent manner and stabilizes BRCA1 mRNA. Cells lacking BRCA1 similar to the cell lacking LKB1 display increased genomic instability and ectopic expression of BRCA1 rescues LKB1 loss-induced sensitivity to genotoxic stress. Collectively, our results demonstrate that LKB1 is a crucial regulator of genome integrity and reveal a novel mechanism for LKB1-mediated tumor suppression with direct therapeutic implications for cancer prevention.

Appendix carcinoid associated with the Peutz-Jeghers syndrome

INTRODUCTION

The Peutz-Jeghers syndrome (PJS) is a rare hereditary, autosomal-dominant disorder.

It is characterized by a gastrointestinal polyposis and mucocutaneous melanic spots. It has also been reported as a precondition for malignancies with a life-time-hazard for cancer up to 93%, caused by a germline mutation in the STK11 gene.

PRESENTATION OF CASE

A 21-year-old man presented with nausea and abdominal pain. He had a known history of PJS since the age of 13 when he was treated for intussusception due to a hamartomatous polyp. Preoperative diagnostics revealed a second intussusception and an extensive intestinal polyposis. Intraoperative findings confirmed the suspected diagnoses and desvagination was performed. Nearly 50 polyps were removed from the small intestinum over several longitudinal sections. As the appendix appeared thickened an appendectomy was performed simultaneously. Histology showed hamartomatous polyps and the incidental finding of a pT1 carcinoid of the appendix. The patient recovered well and needed no further treatment for his carcinoid tumor.

DISCUSSION

The mechanism of carcinogenesis in PJS still remains debatable, although the genetic disorder underlying the syndrome is known. A predisposition for carcinoid tumors also stays questionable. To our knowledge there is no description of an association between carcinoid tumors of the appendix and PJS to date.

CONCLUSION

Life-expectancy in patients with PJS is reduced. Causes are the development of malignancies and complications from the polyps such as intussusception. Since there is no treatment possible main focus must be aimed at early recognition of malignancies and the prevention of complications.

Oral pigmentation in McCune-Albright syndrome

IMPORTANCE

The differential diagnosis for oral lentigines includes several syndromes with important associated systemic findings. McCune-Albright syndrome (MAS), a mosaic condition associated with café au lait pigmentation, is not typically considered a mucosal lentiginosis syndrome. The clinical phenotype of MAS is variable because of mosaicism, but oral pigmentation developing in mid-childhood to early adulthood should be recognized as a clinical feature of MAS.

OBSERVATIONS

We present 4 patients with MAS who developed oral mucosal pigmentation during childhood or early adulthood. All patients had other characteristic findings of MAS including hyperfunctioning endocrinopathies, polyostotic fibrous dysplasia, and café au lait pigmentation.

CONCLUSIONS AND RELEVANCE

Oral pigmentation is an underrecognized finding in MAS and presents later in development compared with the other mucosal lentiginosis syndromes. The diagnosis of MAS is most commonly a clinical diagnosis because mutational analysis is challenging in mosaic conditions. Expanding the cutaneous phenotype to include oral pigmentation further characterizes the clinical findings in this mosaic condition, broadens the differential diagnosis of syndromes with oral pigmentation, and in some cases may aid in earlier diagnosis of MAS.

GNAS is not involved in gastrointestinal tumour formation in Peutz-Jeghers syndrome

Peutz-Jeghers syndrome (PJS), caused by germ-line mutations in LKB1, is characterized by the development of hamartomatous polyps in the gastrointestinal (GI) tract. McCune Albright syndrome (MAS), caused by somatic activating mutations in GNAS, presents with cutaneous, skeletal, and endocrine manifestations. Recently, hamartomatous GI polyps with histological features similar to those in PJS were observed in MAS patients, suggesting a role for GNAS in the pathogenesis of PJS. This study reports the first somatic GNAS mutation analysis in GI tumours of PJS patients. No mutations were observed, suggesting that GNAS is not involved in the pathogenesis of GI tumours in PJS.

Hereditary colorectal cancer syndromes

SUMMARY Colorectal cancer (CRC) is one of the most common malignancies and the second-leading cause of cancer death in both sexes in developed countries. Over the last 25 years, highly penetrant monogenic germline mutations that predispose to CRC and other digestive tumors have been identified, accounting for up to 5% of all CRC cases. Identification and characterization of these disorders have allowed modification of their natural history, with a substantial decrease in morbidity and mortality among high-risk patients. Recognizing hereditary CRC has also impacted predictive genetic testing and personalized medicine based on genomic information. This review summarizes the current knowledge on hereditary CRC regarding pathogenesis, clinical features, diagnostic evaluation and management recommendations.

Clinicopathologic correlations of liver kinase B1, E-cadherin, and N-cadherin expression in non-small cell lung cancer

The role of liver kinase B1 (LKB1) as a tumor suppressor has emerged from the observation of increased risk of malignancy in gastrointestinal tract in Peutz-Jeghers syndrome patients harboring LKB1 gene mutations. LKB1 gene inactivation has recently been demonstrated in a subset of lung carcinoma and has been proven to trigger epithelial-mesenchymal transition in lung adenocarcinoma cells. However, the clinicopathologic significance, particularly prognosis, of LKB1 protein expression remains largely unclear. Using immunohistochemistry, we investigated the correlations between LKB1, E-cadherin, and N-cadherin expression and clinicopathologic parameters of lung cancer patients. Immunohistochemistry on specimens of the normal bronchial epithelium revealed that LKB1 was strongly or moderately expressed in the cytoplasm, and E-cadherin was expressed clearly on the cell membrane, whereas N-cadherin was absent or only weakly expressed at the membrane and/or in the cytoplasm. In contrast, in lung cancer samples, LKB1 expression was absent or decreased in 25.7% (29/113) cases accompanied with loss of membranous E-cadherin expression (25/29, P = 0.009) and increased membranous and/or cytoplasmic N-cadherin expression (18/29, P = 0.007). Loss of LKB1 expression positively correlated with histologic type (P=0.001), poor differentiation (P = 0.004), and adverse prognosis (P < 0.001). Moreover, loss of LKB1 expression correlated with lymph node metastasis (P=0.022) in lung adenocarcinoma samples and was an independent factor that impacted lung adenocarcinoma patients' prognosis (P = 0.003). Therefore, loss of LKB1 expression correlates with epithelial-mesenchymal transition markers and may be a useful marker of poor survival for the patient with lung adenocarcinoma.

10 rare tumors that warrant a genetics referral

The number of described cancer susceptibility syndromes continues to grow, as does our knowledge on how to manage these syndromes with the aim of early detection and cancer prevention. Oncologists now have greater responsibility to recognize patterns of cancer that warrant referral for a genetics consultation. While some patterns of common cancers are easy to recognize as related to hereditary cancer syndromes, there are a number of rare tumors that are highly associated with cancer syndromes yet are often overlooked given their infrequency. We present a review of ten rare tumors that are strongly associated with hereditary cancer predisposition syndromes: adrenocortical carcinoma, carcinoid tumors, diffuse gastric cancer, fallopian tube/primary peritoneal cancer, leiomyosarcoma, medullary thyroid cancer, paraganglioma/pheochromocytoma, renal cell carcinoma of chromophobe, hybrid oncocytoic, or oncocytoma histology, sebaceous carcinoma, and sex cord tumors with annular tubules. This review will serve as a guide for oncologists to assist in the recognition of rare tumors that warrant referral for a genetic consultation.