High cancer risk in Peutz-Jeghers syndrome: a systematic review and surveillance recommendations

Resolving inherited and de novo germline predisposing sequence variants by means of whole exome trio analyses in childhood hematological malignancies

Molecular screening tools have significantly eased the assessment of potential germline susceptibility factors that may underlie the development of pediatric malignancies. Most of the hitherto published studies utilize the comparative analyses of the respective patients' germline and tumor tissues for this purpose. Since this approach is not able to discriminate between de novo and inherited sequence variants, we performed whole exome trio analyses in a consecutive series of 131 children with various forms of hematologic malignancies and their parents. In total, we identified 458 de novo variants with a range from zero to 28 (median value = 3) per patient, although most of them (58%) had only up to three per exome. Overall, we identified bona fide cancer predisposing alterations in five of the investigated 131 (3.8%) patients. Three of them had de novo pathogenic lesions in the SOS1, PTPN11 and TP53 genes and two of them parentally inherited ones in the STK11 and PMS2 genes that are specific for a Peutz-Jeghers and a constitutional mismatch repair deficiency (CMMRD) syndrome, respectively. Notwithstanding that we did not identify a disease-specific alteration in the two cases with the highest number of de novo variants, one of them developed two almost synchronous malignancies: a myelodysplastic syndrome and successively within two months a cerebral astrocytoma. Moreover, we also found that the rate of de novo sequence variants in the offspring increased especially with the age of the father, but less so with that of the mother. We therefore conclude that trio analyses deliver an immediate overview about the inheritance pattern of the entire spectrum of sequence variants, which not only helps to securely identify the de novo or inherited nature of genuinely disease-related lesions, but also of all other less obvious variants that in one or the other way may eventually advance our understanding of the disease process.

Genetic Mutations of Pancreatic Cancer and Genetically Engineered Mouse Models

Simple Summary

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive malignancy. Recent multi-gene analysis approaches such as next-generation sequencing have provided useful information on the molecular characterization of pancreatic tumors. Different types of pancreatic cancer and precursor lesions are characterized by specific molecular alterations. Genetically engineered mouse models (GEMMs) of PDAC are useful tools to understand the roles of altered genes. Most GEMMs are driven by oncogenic Kras, and can recapitulate the histological and molecular hallmarks of human PDAC and comparable precursor lesions. In this review, we summarize the main molecular alterations found in pancreatic neoplasms and GEMMs developed based on these alterations.

Abstract

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive malignancy, and the seventh leading cause of cancer-related deaths worldwide. An improved understanding of tumor biology and novel therapeutic discoveries are needed to improve overall survival. Recent multi-gene analysis approaches such as next-generation sequencing have provided useful information on the molecular characterization of pancreatic tumors. Different types of pancreatic cancer and precursor lesions are characterized by specific molecular alterations. Genetically engineered mouse models (GEMMs) of PDAC are useful to understand the roles of altered genes. Most GEMMs are driven by oncogenic Kras, and can recapitulate the histological and molecular hallmarks of human PDAC and comparable precursor lesions. Advanced GEMMs permit the temporally and spatially controlled manipulation of multiple target genes using a dual-recombinase system or CRISPR/Cas9 gene editing. GEMMs that express fluorescent proteins allow cell lineage tracing to follow tumor growth and metastasis to understand the contribution of different cell types in cancer progression. GEMMs are widely used for therapeutic optimization. In this review, we summarize the main molecular alterations found in pancreatic neoplasms, developed GEMMs, and the contribution of GEMMs to the current understanding of PDAC pathobiology. Furthermore, we attempted to modify the categorization of altered driver genes according to the most updated findings.

Gastric-type adenocarcinoma of the cervix in patients with Peutz-Jeghers syndrome: a systematic review of the literature with proposed screening guidelines

OBJECTIVES

To perform a systematic review of gastric-type adenocarcinoma of the cervix and lobular endocervical glandular hyperplasia (a possible precursor lesion) in Peutz-Jeghers syndrome, and to analyze data from the literature, along with our institutional experience, to determine recommendations for screening and detection.

METHODS

A comprehensive literature searc and retrospective search of pathology records at our institutio were conducted. Articles were screened by two independent reviewers. Case reports/series on lobular endocervical glandular hyperplasia/gastric-type adenocarcinoma of the cervix in Peutz-Jeghers syndrome were included. Demographic, clinical, and radiologic information was collected.

RESULTS

A total of 1564 publications were reviewed; 38 met the inclusion criteria. Forty-nine were included in the analysis (43 from the literature, 6 from our institution). Forty-three reported on gastric-type adenocarcinoma alone, 4 on lobular endocervical glandular hyperplasia alone, and 2 on concurrent lobular endocervical glandular hyperplasia/gastric-type adenocarcinoma. Median age at diagnosis was 17 (range, 4-52) for patients with lobular endocervical glandular hyperplasia alone and 35 (range, 15-72) for those with gastric-type adenocarcinoma. The most common presenting symptoms were abdominal/pelvic pain and vaginal bleeding/discharge. Imaging was reported for 27 patients; 24 (89%) had abnormal cervical features. Papanicolaou (Pap) smear prior to diagnosis was reported for 12 patients; 6 (50%) had normal cytology, 4 (33%) atypical glandular cells, and 2 (17%) atypical cells not otherwise specified. Patients with gastric-type adenocarcinoma (n=45) were treated with surgery alone (n=16), surgery/chemotherapy/radiation (n=11), surgery/chemotherapy (n=9), surgery/radiation (n=5), or radiation/chemotherapy (n=4). Twelve (27%) of 45 patients recurred; median progression-free survival was 10 months (range, 1-148). Twenty patients (44%) died; median overall survival was 26 months (range, 2-156). Thirteen patients (27%) were alive with no evidence of disease.

CONCLUSIONS

Gastric-type adenocarcinoma in Peutz-Jeghers syndrome is associated with poor outcomes and short progression-free and overall survival. Screening recommendations, including pathognomonic symptom review and physical examination, with a low threshold for imaging and biopsy, may detect precursor lesions and early-stage gastric-type adenocarcinoma, leading to better outcomes in this high-risk population.

PROSPERO REGISTRATION NUMBER

CRD42019118151.

Hotspots and trends in liver kinase B1 research: A bibliometric analysis

Introduction

In the past 22 years, a large number of publications have reported that liver kinase B1 (LKB1) can regulate a variety of cellular processes and play an important role in many diseases. However, there is no systematic bibliometric analysis on the publications of LKB1 to reveal the research hotspots and future direction.

Methods

Publications were retrieved from the Web of Science Core Collection (WoSCC), Scopus, and PubMed databases. CiteSpace and VOSviewer were used to analysis the top countries, institutions, authors, source journals, discipline categories, references, and keywords.

Results

In the past 22 years, the number of LKB1 publications has increased gradually by year. The country, institution, author, journals that have published the most articles and cited the most frequently were the United States, Harvard University, Prof. Benoit Viollet, Journal of Biochemistry and Plos One. The focused research hotspot was the molecular functions of LKB1. The emerging hotspots and future trends are the clinical studies about LKB1 and co-mutated genes as biomarkers in tumors, especially in lung adenocarcinoma.

Conclusions

Our research could provide knowledge base, frontiers, emerging hotspots and future trends associated with LKB1 for researchers in this field, and contribute to finding potential cooperation possibilities.

Detection and analysis of common pathogenic germline mutations in Peutz-Jeghers syndrome

BACKGROUND

Different types of pathogenic mutations may produce different clinical phenotypes, but a correlation between Peutz-Jeghers syndrome (PJS) genotype and clinical phenotype has not been found. Not all patients with PJS have detectable mutations of the STK11/LKB1 gene, what is the genetic basis of clinical phenotypic heterogeneity of PJS? Do PJS cases without STK11/LKB1 mutations have other pathogenic genes? Those are clinical problems that perplex doctors.

AIM

The aim was to investigate the specific gene mutation of PJS, and the correlation between the genotype and clinical phenotype of PJS.

METHODS

A total of 24 patients with PJS admitted to the Air Force Medical Center, PLA (formerly the Air Force General Hospital, PLA) from November 1994 to January 2020 were randomly selected for inclusion in the study. One hundred thirty-nine common hereditary tumor-related genes including STK11/LKB1 were screened and analyzed for pathogenic germline mutations by high-throughput next-generation sequencing (NGS). The mutation status of the genes and their relationship with clinical phenotypes of PJS were explored.

RESULTS

Twenty of the 24 PJS patients in this group (83.3%) had STK11/LKB1 gene mutations, 90% of which were pathogenic mutations, and ten had new mutation sites. Pathogenic mutations in exon 7 of STK11/LKB1 gene were significantly lower than in other exons. Truncation mutations are more common in exons 1 and 4 of STK11/LKB1, and their pathogenicity was significantly higher than that of missense mutations. We also found SLX4 gene mutations in PJS patients.

CONCLUSION

PJS has a relatively complicated genetic background. Changes in the sites responsible for coding functional proteins in exon 1 and exon 4 of STK11/LKB1 may be one of the main causes of PJS. Mutation of the SLX4 gene may be a cause of genetic heterogeneity in PJS.

Peutz-Jeghers Syndrome and the Role of Imaging: Pathophysiology, Diagnosis, and Associated Cancers

Simple Summary

The Peutz-Jeghers Syndrome is a rare autosomal dominant syndrome characterized by mucocutaneous pigmentations, multiple gastrointestinal hamartomatous polyps, and an elevated risk of malignancy. Awareness of various Peutz-Jeghers Syndrome imaging patterns, associated malignancies, and their complications is crucial for accurate imaging interpretation and patient management. In this manuscript, we provide an overview of this condition, associated malignancies, and imaging surveillance protocols.

Abstract

The Peutz-Jeghers Syndrome (PJS) is an autosomal dominant neoplastic syndrome defined by hamartomatous polyps through the gastrointestinal tract, development of characteristic mucocutaneous pigmentations, and an elevated lifetime cancer risk. The majority of cases are due to a mutation in the STK11 gene located at 19p13.3. The estimated incidence of PJS ranges from 1:50,000 to 1:200,000. PJS carries an elevated risk of malignancies including gastrointestinal, breast, lung, and genitourinary (GU) neoplasms. Patients with PJS are at a 15- to 18-fold increased malignancy risk relative to the general population. Radiologists have an integral role in the diagnosis of these patients. Various imaging modalities are used to screen for malignancies and complications associated with PJS. Awareness of various PJS imaging patterns, associated malignancies, and their complications is crucial for accurate imaging interpretation and patient management. In this manuscript, we provide a comprehensive overview of PJS, associated malignancies, and surveillance protocols.

From APC to the genetics of hereditary and familial colon cancer syndromes

Hereditary colorectal cancer (CRC) syndromes attributable to high penetrance mutations represent 9-26% of young-onset CRC cases. The clinical significance of many of these mutations is understood well enough to be used in diagnostics and as an aid in patient care. However, despite the advances made in the field, a significant proportion of familial and early-onset cases remains molecularly uncharacterized and extensive work is still needed to fully understand the genetic nature of CRC susceptibility. With the emergence of next-generation sequencing and associated methods, several predisposition loci have been unraveled, but validation is incomplete. Individuals with cancer-predisposing mutations are currently enrolled in life-long surveillance, but with the development of new treatments, such as cancer vaccinations, this might change in the not so distant future for at least some individuals. For individuals without a known cause for their disease susceptibility, prevention and therapy options are less precise. Herein, we review the progress achieved in the last three decades with a focus on how CRC predisposition genes were discovered. Furthermore, we discuss the clinical implications of these discoveries and anticipate what to expect in the next decade.

Pancreatic cancer in 2021: What you need to know to win

Pancreatic cancer is one of the solid tumors with the worst prognosis. Five-year survival rate is less than 10%. Surgical resection is the only potentially curative treatment, but the tumor is often diagnosed at an advanced stage of the disease and surgery could be performed in a very limited number of patients. Moreover, surgery is still associated with high post-operative morbidity, while other therapies still offer very disappointing results. This article reviews every aspect of pancreatic cancer, focusing on the elements that can improve prognosis. It was written with the aim of describing everything you need to know in 2021 in order to face this difficult challenge.

Inherited Pancreatic Cancer Syndromes and High-Risk Screening

Pancreatic cancer is the third leading cause of cancer death in the United States, with a 5-year survival rate of 9%. Individuals with inherited pancreatic cancer syndromes are at an increased risk for developing pancreatic cancer and may benefit from pancreatic cancer surveillance with the goal to detect and intervene on early-stage cancer or high-risk precursor lesions. Given the screening implications for family members and therapeutic implications for probands, all patients diagnosed with pancreatic cancer are recommended to undergo germline genetic testing.

Hamartomatous polyposis syndrome associated malignancies: Risk, pathogenesis and endoscopic surveillance

Hamartomatous polyposis syndromes (HPS) are a heterogeneous spectrum of diseases that are characterized by diffuse hamartomatous polyps lining the gastrointestinal (GI) tract together with extra-GI manifestations. Classical HPS includes juvenile polyposis syndrome, Peutz-Jeghers syndrome, PTEN hamartoma tumor syndrome and hereditary mixed polyposis syndrome. Patients with HPS have a higher risk of GI and extra-GI malignancies than the general population, although the underlying mechanisms remain unclear and are obviously different from the carcinogenesis of classical adenocarcinoma and colitis-associated malignancy. In this review we aimed to clarify the risks, possible mechanism and endoscopic surveillance of HPS-associated GI malignancies.

BRCA mutations and gastrointestinal cancers: When to expect the unexpected?

BRCA1/2 pathogenic variants are widely known as major risk factors mainly for breast and ovarian cancer, while their role in gastrointestinal (GI) malignancies such as colorectal cancer (CRC), gastric cancer and oesophageal cancer (OeC) is still not well established. The main objective of this review is to summarise the available evidence on this matter. The studies included in the review were selected from PubMed/GoogleScholar/ScienceDirect databases to identify published articles where BRCA1/2 pathogenic variants were assessed either as a risk factor or a prognostic/predictive factor in these malignancies. Our review suggests that BRCA1/2 might have a role as a risk factor for colorectal, gastric and OeC, albeit with differences among these diseases: In particular BRCA1 seems to be much more frequently mutated in CRC whereas BRCA2 appears to be much more closely associated with gastric and OeC. Early-onset cancer seems to be also associated with BRCA1/2 mutations and a few studies suggest a positive prognostic role of these mutations. The assessment of a potentially predictive role of these mutations is hampered by the fact that most patients with these diseases have been treated with platinum compounds, where it is expected that a higher probability of response should be seen. A few clinical trials focused on poly (ADP-ribose) polymerase inhibitors use in GI cancers are currently ongoing.

Inherited Predisposition to Gastric Cancer

Approximately 10% of patients with gastric cancer show familial aggregation and up to 3% are related to an inherited cancer syndrome. There are multiple germline pathogenic variants and cancer syndromes associated with an increased risk of gastric cancer. Appropriate assessment of familial and genetic risk may allow a personalized approach to gastric cancer prevention through screening and risk-reducing surgeries. The ability to better identify carriers with pathogenic genetic variants associated with gastric cancer before a diagnosis of cancer requires effective genetic risk assessment and testing, followed by optimal screening and surveillance recommendations to further reduce the morbidity and mortality.

Pancreatic cancer epidemiology: understanding the role of lifestyle and inherited risk factors

Pancreatic cancer is a leading cause of cancer death worldwide and its global burden has more than doubled over the past 25 years. The highest incidence regions for pancreatic cancer include North America, Europe and Australia, and although much of this increase is due to ageing worldwide populations, there are key modifiable risk factors for pancreatic cancer such as cigarette smoking, obesity, diabetes and alcohol intake. The prevalence of these risk factors is increasing in many global regions, resulting in increasing age-adjusted incidence rates for pancreatic cancer, but the relative contribution from these risk factors varies globally due to variation in the underlying prevalence and prevention strategies. Inherited genetic factors, although not directly modifiable, are an important component of pancreatic cancer risk, and include pathogenic variants in hereditary cancer genes, genes associated with hereditary pancreatitis, as well as common variants identified in genome-wide association studies. Identification of the genetic changes that underlie pancreatic cancer not only provides insight into the aetiology of this cancer but also provides an opportunity to guide early detection strategies. The goal of this Review is to provide an up-to-date overview of the established modifiable and inherited risk factors for pancreatic cancer.

Advances in the epidemiology of pancreatic cancer: Trends, risk factors, screening, and prognosis

Pancreatic cancer is a malignancy with poor prognosis and high mortality. The recent increase in pancreatic cancer incidence and mortality has resulted in an increased number of studies on its epidemiology. This comprehensive and systematic literature review summarizes the advances in the epidemiology of pancreatic cancer, including its epidemiological trends, risk factors, risk prediction models, screening modalities, and prognosis. The risk factors for pancreatic cancers can be categorized as those related to individual characteristics, lifestyle and environment, and disease status. Several prediction models for pancreatic cancer have been developed in populations with new-onset diabetes or a family history of pancreatic cancer; however, these models require further validation. Despite recent progress in pancreatic cancer screening, the quantity and quality of related studies are also unsatisfactory, especially with respect to the identification of high-risk populations and development of effective screening modality. Apart from the populations with familial genetic risk and those at a high risk of sporadic pancreatic cancer, risk factors such as new-onset diabetes may be a new direction for timely intervention. We hope this work will provide new ideas for further prevention and treatment of pancreatic cancer.

Pancreas in Hereditary Syndromes: Cross-sectional Imaging Spectrum

A wide spectrum of hereditary syndromes predispose patients to distinct pancreatic abnormalities, including cystic lesions, recurrent pancreatitis, ductal adenocarcinoma, nonductal neoplasms, and parenchymal iron deposition. While pancreatic exocrine insufficiency and recurrent pancreatitis are common manifestations in cystic fibrosis and hereditary pancreatitis, pancreatic cysts are seen in von Hippel-Lindau disease, cystic fibrosis, autosomal dominant polycystic kidney disease, and McCune-Albright syndrome. Ductal adenocarcinoma can be seen in many syndromes, including Peutz-Jeghers syndrome, familial atypical multiple mole melanoma syndrome, Lynch syndrome, hereditary breast and ovarian cancer syndrome, Li-Fraumeni syndrome, and familial pancreatic cancer syndrome. Neuroendocrine tumors are commonly seen in multiple endocrine neoplasia type 1 syndrome and von Hippel-Lindau disease. Pancreatoblastoma is an essential component of Beckwith-Wiedemann syndrome. Primary hemochromatosis is characterized by pancreatic iron deposition. Pancreatic pathologic conditions associated with genetic syndromes exhibit characteristic imaging findings. Imaging plays a pivotal role in early detection of these conditions and can positively affect the clinical outcomes of those at risk for pancreatic malignancies. Awareness of the characteristic imaging features, imaging-based screening protocols, and surveillance guidelines is crucial for radiologists to guide appropriate patient management. ^©RSNA, 2021.

A novel pathogenic splice site variation in STK11 gene results in Peutz-Jeghers syndrome

Background

Peutz–Jeghers syndrome (PJS) is a rare autosomal dominantly inherited disease resulting in multiple gastrointestinal hamartomatous polyps, mucocutaneous pigmentation, and an increased risk of various types of cancer, and is caused by variations in the serine/threonine protein kinase STK11 (LKB1).

Methods

STK11 gene variations were identified by analyzing STK11 cDNA and genomic DNA. Minigenes carrying the wild‐type and mutant sequences were subjected to in vitro splicing assay to dissect the features of these mutations. The different distribution of wild‐type and mutant protein in cells were tested by Immunofluorescence assays and the functional analysis of the variation were performed using Western blot.

Results

A novel heterozygous splice‐acceptor site variation (c.921‐2 A>C) in intron 7 of the STK11 gene which is co‐segregates with the PJS phenotypes in the proband and all the affected family members and three previously reported variations (c.180C>G, c.580G>A, c.787_790del) were identified in the four families. The c.921‐2 A>C substitution resulted in the inactivation of a splice site and the utilization of a cryptic splice acceptor site surrounding exon 8, generating three different aberrant RNA transcripts, leading to frameshift translation and protein truncation. The results of minigenes indicated that the spliceosome can use a variety of 3’ acceptor site sequences to pair with a given 5’ donor site. The immunofluorescent visualization showed that the distribution of mutant STK11 was different from that of wild‐type STK11, suggesting the mutation may be the causative effect on the dysfunction of the mutant protein. The rescue experiments indicated that the failure of suppressing mTOR phosphorylation by shRNA STK11 could be eliminated by supply of wild‐type STK11 rather than mutant STK11.

Conclusion

We identified a novel heterozygous mutation (c.921‐2 A>C) in the STK11 in a Chinese PJS family. Haploinsufficiency of STK11 might contribute to the pathogenesis of the disease.

Curing pancreatic cancer

The distinct biology of pancreatic cancer with aggressive and early invasive tumor cells, a tumor promoting microenvironment, late diagnosis, and high therapy resistance poses major challenges on clinicians, researchers, and patients. In current clinical practice, a curative approach for pancreatic cancer can only be offered to a minority of patients and even for those patients, the long-term outcome is grim. This bitter combination will eventually let pancreatic cancer rise to the second leading cause of cancer-related mortalities. With surgery being the only curative option, complete tumor resection still remains the center of pancreatic cancer treatment. In recent years, new developments in neoadjuvant and adjuvant treatment have emerged. Together with improved perioperative care including complication management, an increasing number of patients have become eligible for tumor resection. Basic research aims to further increase these numbers by new methods of early detection, better tumor modelling and personalized treatment options. This review aims to summarize the current knowledge on clinical and biologic features, surgical and non-surgical treatment options, and the improved collaboration of clinicians and basic researchers in pancreatic cancer that will hopefully result in more successful ways of curing pancreatic cancer.

Peutz-Jeghers syndrome

PURPOSE OF REVIEW

Peutz-Jeghers syndrome is a rare, autosomal dominant, hereditary polyposis syndrome defined by gastrointestinal hamartomas and mucocutaneous pigmentations, caused by a germline mutation in the serine/ threonine kinase 11 or liver kinase B1 (STK11/LKB1) genes. Hamartomatous polyps located throughout the gastrointestinal tract can be complicated by bleeding and small bowel intussusception, potentially leading to the need for emergency surgery. Individuals suffering from Peutz-Jeghers syndrome have an increased lifetime risk of various forms of cancer (gastrointestinal, pancreatic, lung, breast, uterine, ovarian and testicular). Surveillance should lead to the prevention of complications and thus a reduction in mortality and morbidity of patients.

RECENT FINDINGS

A combined approach based on wireless capsule endoscopy, magnetic resonance enterography and device-assisted enteroscopy is effective in reduction of the polyp burden and thus decreasing the risk of bleeding and intussusception. Current guidelines for screening and surveillance are mostly based on expert opinion rather than evidence.

SUMMARY

Peutz-Jeghers syndrome is an emerging disease that significantly affects the quality of life enjoyed by patients. Despite of all the progress in improved early diagnostics, options for advanced endoscopic therapy and elaborate surveillance, acute and chronic complications decrease the life expectancy of patients suffering from Peutz-Jeghers syndrome.

A Case of Peutz-Jeghers Syndrome Presenting With an Inoperable Periampullary Tumor

Peutz-Jeghers syndrome (PJS) is a syndrome characterized by multiple hamartomatous polyps in the gastrointestinal system and melanin pigments accumulating in the skin and mucous membranes. Patients with PJS have an increased risk of gastrointestinal malignancies. In this syndrome, pancreatic cancer is primarily detected in older ages. In this article, we present a case of a patient with an unresectable periampullary tumor and PJS.

Clinical Perspective on Proteomic and Glycomic Biomarkers for Diagnosis, Prognosis, and Prediction of Pancreatic Cancer

Pancreatic ductal adenocarcinoma (PDAC) is known as a highly aggressive malignant disease. Prognosis for patients is notoriously poor, despite improvements in surgical techniques and new (neo)adjuvant chemotherapy regimens. Early detection of PDAC may increase the overall survival. It is furthermore foreseen that precision medicine will provide improved prognostic stratification and prediction of therapeutic response. In this review, omics-based discovery efforts are presented that aim for novel diagnostic and prognostic biomarkers of PDAC. For this purpose, we systematically evaluated the literature published between 1999 and 2020 with a focus on protein- and protein-glycosylation biomarkers in pancreatic cancer patients. Besides genomic and transcriptomic approaches, mass spectrometry (MS)-based proteomics and glycomics of blood- and tissue-derived samples from PDAC patients have yielded new candidates with biomarker potential. However, for reasons discussed in this review, the validation and clinical translation of these candidate markers has not been successful. Consequently, there has been a change of mindset from initial efforts to identify new unimarkers into the current hypothesis that a combination of biomarkers better suits a diagnostic or prognostic panel. With continuing development of current research methods and available techniques combined with careful study designs, new biomarkers could contribute to improved detection, prognosis, and prediction of pancreatic cancer.

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.

Elevated hemoglobin A1c is associated with the presence of pancreatic cysts in a high-risk pancreatic surveillance program

Background

Emerging evidence demonstrates that surveillance of individuals at high-risk (HRIs) of developing pancreatic adenocarcinoma allows for identification and treatment of resectable tumors with improved survival. Population-based data suggest that hyperglycemia may be present up to three years before the development of pancreatic cancer. We investigated whether elevated hemoglobin A1c (HbA1c) is associated with the development of pancreatic cysts in a pancreatic surveillance program.

Methods

We performed a retrospective study of HRIs who underwent pancreatic surveillance at a single institution between May 2013 and March 2019, according to published criteria. We collected demographic information, clinical data including HbA1c, and imaging results. We compared data using univariable and multivariable analyses. Our primary outcome was the presence of pancreatic cysts on initial surveillance in patients with elevated HbA1c.

Results

Ninety-eight patients underwent surveillance imaging via EUS or MRCP and seventy-four patients met inclusion criteria. Thirty patients were found to have cysts on initial imaging. Older age (p < 0.01) and HbA1c in the prediabetic range or higher (p = 0.01) were associated with the presence of cysts or solid lesions on univariable analysis. After controlling for confounders, age (aOR 9.08, 95% CI 2.29–36.10), and HbA1c > 5.7% (aOR 5.82, 95% CI 1.50–22.54) remained associated with presence of cysts and solid lesions in HRIs. In patients with cysts or solid lesions there was a strong association between increased age and elevated HbA1c (p < 0.01).

Conclusion

HRIs with elevated HbA1c were more likely to have pancreatic cysts compared to individuals with lower HbA1c on initial imaging in a pancreatic surveillance program. These findings may help tailor the surveillance protocols for those at increased risk of developing pancreatic adenocarcinoma.

LKB1 and cancer: The dual role of metabolic regulation

Liver kinase B1 (LKB1) is an essential serine/threonine kinase frequently associated with Peutz-Jeghers syndrome (PJS). In this review, we provide an overview of the role of LKB1 in conferring protection to cancer cells against metabolic stress and promoting cancer cell survival and invasion. This carcinogenic effect contradicts the previous conclusion that LKB1 is a tumor suppressor gene. Here we try to explain the contradictory effect of LKB1 on cancer from a metabolic perspective. Upon deletion of LKB1, cancer cells experience increased energy as well as oxidative stress, thereby causing genomic instability. Meanwhile, mutated LKB1 cooperates with other metabolic regulatory genes to promote metabolic reprogramming that subsequently facilitates adaptation to strong metabolic stress, resulting in development of a more aggressive malignant phenotype. We aim to specifically discuss the contradictory role of LKB1 in cancer by reviewing the mechanism of LKB1 with an emphasis on metabolic stress and metabolic reprogramming.

Appendiceal cancer leading to intussusception detected incidentally during follow-up for Peutz-Jeghers syndrome

Peutz-Jeghers syndrome is an autosomal dominant disorder characterized by hamartomatous polyposis, pigmentation, and malignant tumors. We report a case of ileocecal carcinoma that was incidentally detected during follow-up for Peutz-Jeghers syndrome. A 39-year-old man with solitary Peutz-Jeghers syndrome had undergone three abdominal surgeries. He had been followed up via upper and lower gastrointestinal endoscopy and small intestinal endoscopy. In the endoscopic examination of the lower gastrointestinal tract, a 35 mm large, bumpy, elevated lesion was observed in the cecum. This lesion was not observed 9 months earlier during lower endoscopy. Biopsy of the specimen confirmed tubulovillous adenoma and carcinoma. This lesion was judged to be an indication for operation, and we performed ileocecectomy + D3 lymph node dissection. From the excised specimen, poorly differentiated carcinoma and adenoma components in contact with Peutz-Jeghers-type polyps in the appendix were recognized. A review of the computed tomography image obtained 2 years ago confirmed appendiceal swelling. We suspect that the ileocecal carcinoma in the appendix may have rapidly developed within the 9 months, and was incidentally detected on lower endoscopic examination during follow-up. For the prevention of appendicular tumorigenesis, prophylactic appendectomy may be considered in certain cases during follow-up for Peutz-Jeghers syndrome.

Interesting case of dual pathology: Crohn's disease and Peutz-Jeghers syndrome

An 18-year-old man presented with fever, night sweats and progressive weight loss over 2 months. He had a history of Peutz-Jeghers syndrome (PJS) complicated by previous intussusception requiring left hemicolectomy. Colonoscopy revealed deep punched out ulceration throughout the colon with multiple polyps. He was investigated for tuberculosis based on his occupation as dairy farmer. Following a negative QuantiFERON test, he was started on infliximab as emergency therapy and made a good recovery at 6 months follow-up. We describe a case of newly diagnosed Crohn's disease (CD) in an adolescent with a background diagnosis of PJS. While inflammatory bowel disease, such as CD, is common in the UK, the association with PJS is very rare, with only two existing case reports in the literature.

PEUTZ-JEGHERS SYNDROME IN RESOURCE-LIMITED SCENARIO

ABSTRACT BACKGROUND: Peutz-Jeghers Syndrome (PJS) is a rare, autosomal dominant disease, caused by deletions in the chromosome 19p33.3/ gene LKB1/STK11. These mutations inactivate a serine/threonine kinase and predispose to carcinogenesis. In PJS, tumors of the gastrointestinal, testicles, pulmonary, breast, pancreas, uterus and ovaries can be found. OBJECTIVE: To evaluate demographics, clinical presentation and complication/outcomes of pediatric patients presenting with Peutz-Jeghers syndrome (PJS), as well as to present and discuss management in the context of limited resources. METHODS: We conducted a retrospective chart review of a cohort of six patients, who were diagnosed and/or followed at the Clinics Hospital, University of Campinas - Sao Paulo/Brazil, between 2000 and 2018. Data analyzed included gender, age of presentation, age of diagnosis, family history, PJS complications. RESULTS: Median age of diagnosis of 6.7 years, with a mean time of follow-up of 8.1 years. Mucocutaneous pigmentation was universally present. Half of the patients had a known family history at the time of diagnosis. On follow up, intestinal intussusception was documented in four out of six patients, in most (three), in different locations and in multiple occasions. The active investigation of siblings and parents of the index case led to the diagnosis of three first-degree relatives in the present case series. CONCLUSION: In this first pediatric PJS Brazilian case series, we report a wide spectrum of PJS manifestations and complications. In a resource limited scenario, despite limitations for the surveillance of complications, the relative frequency of complications was not higher than historically reported.

An unusual presentation revealing Peutz-Jeghers syndrome in adult

Introduction

Peutz-Jeghers syndrome (PJS) is a rare hereditary disease characterized by hyperpigmentation on the lips and oral cavity and gastrointestinal hamartomatous polyps. The most common complications in PJS patients are bleeding, bowel obstruction and intussusception.

Presentation of case

We hereby report a case of a 33-year-old female, without a family history of the disease, who presented to the emergency room with acute abdominal pain, bloating and not passing gas. On abdominal examination, upper abdominal and periumbilical tenderness was found. Computed tomography (CT) of the abdomen demonstrated suspected ascending colon intussusception. The patient underwent a mid-line laparotomy that showed an ileocolic intussusception. Reduction of this intussusception was successfully done with resection of the affected segment that showed presence of two pedunculated polyps. The specimen was sent thereafter to our department for histopathological evaluation, which confirmed the diagnosis of hamartomatous Peutz-Jeghers polyps with no malignancy. Afterwards, the patient was carefully reexamined and the physical examination revealed multiple pigmented spots on the face and lips. Thus, the diagnosis of Peutz-Jeghers syndrome was made.

Discussion

PJS is a rare autosomal dominant disorder that often remain undiagnosed for many years. Acute complications such as intestinal obstruction secondary to intussusception is one of infrequent revealing symptoms.

Conclusion

Early identification, in patients with PJS and family members, as well as close cancer surveillance can improve certainly prognosis in these individuals.

Distinct promoter methylation patterns of LKB1 in the hamartomatous polyps of Peutz-Jeghers syndrome and its potential in gastrointestinal malignancy prediction

Background

Peutz-Jeghers Syndrome (PJS) is known as a rare inherited polyposis due to the malfunction of serine/threonine kinase gene LKB1. However, not all of PJS patients carry LKB1 germline mutation. Previous researches have observed the elevated DNA methylation level in PJS polyps. Nevertheless, the mechanism of such abnormal and its impact on PJS patients remains to be fully described.

Results

The results proved a significant increase on the methylation level of LKB1 promoter in PJS polyps compared with normal colon biopsies through bisulfite PCR followed by Sanger sequencing. Moreover, the methylation pattern in PJS polyps could be further categorized as three different scenarios: hypermethylated, hemimethylated and hypomethylated pattern. Furthermore, immunohistochemistry of DNMT1/3a/3b suggested the up-regulation of DNMT1 and 3a might participate the epigenetic alternation of LKB1 in PJS polyps. Logistic regression suggested hypomethylated LKB1 promoter in PJS polyps as a risk factor for gastrointestinal malignancies in PJS patients.

Conclusions

The promoter methylation level of LKB1 gene in PJS polyps is generally elevated compared with normal colon mucosa. Yet not all of PJS polyps carry hypermethylated LKB1 promoter. Hypomethylation in this region has linked to malignant tumors in PJS patients. Given the rarity of PJS, this work together with previous researches, have proved the importance of LKB1 promoter methylation in PJS development and prognosis.

A case of jejunal solitary Peutz-Jeghers polyp with intussusception identified by double-balloon enteroscopy

Solitary Peutz-Jeghers polyp is a rare hamartomatous polyp that has similar histologic characteristics with those of polyps in Peutz-Jeghers syndrome, without associated mucocutaneous hyperpigmentation and a family history. Previous reports indicated that solitary Peutz-Jeghers polyp is rarely found in the small intestine. We experienced a rare case of jejunal solitary Peutz-Jeghers polyp. A 29-year-old man was admitted to our hospital with a 6-month history of upper abdominal pain. He had no hyperpigmentation or a family history of Peutz-Jeghers syndrome. Abdominal computed tomography showed a 3-cm tumor-like structure at the tip of a mildly intussuscepted jejunum. Per oral double-balloon enteroscopy revealed a 3-cm pedunculated polyp in the jejunum. The patient underwent partial jejunal resection under laparotomy. Macroscopically, the surgical specimen showed a pedunculated polyp, measuring 30 × 15 × 10 mm in size, with lobulated head. Histopathologic examination revealed irregular aggregation of hyperplastic crypts with branching muscular bundles originating from the muscularis mucosae. Based on these histologic findings, we finally diagnosed the patient as a solitary Peutz-Jeghers polyp in the jejunum. The present case indicated that solitary Peutz-Jeghers polyp should be considered in a patient with solitary hamartomatous polyp in the gastrointestinal tract.

Deleterious mis-splicing of STK11 caused by a novel single-nucleotide substitution in the 3' polypyrimidine tract of intron five

Background

Pathogenic variants in STK11, also designated as LKB1, cause Peutz–Jeghers syndrome, which is a rare autosomal dominant disorder characterized by mucocutaneous pigmentation changes, polyposis, and a high risk of cancer.

Methods

A male meeting the clinical diagnostic criteria for Peutz–Jeghers syndrome underwent next‐generation sequencing. To validate the predicted splicing impact of a detected STK11 variant, we performed RNA‐Seq on mRNA extracted from patient‐derived Epstein‐Barr virus‐transformed lymphocytes treated with cycloheximide to inhibit nonsense‐mediated decay ex vivo.

Results

Blood testing identified a novel single‐nucleotide substitution, NM_000455.4:c.735‐10C>A, at the end of the 3′ polypyrimidine tract of intron five in STK11. RNA‐Seq confirmed a predicted eight base pair insertion in the mRNA transcript. Following inhibition of nonsense‐mediated decay, the out‐of‐frame insertion was detected in 50% of all RNA‐Seq reads. This confirmed a strong, deleterious splicing impact of the variant.

Conclusion

We characterized a novel likely pathogenic germline variant in intron five of STK11 associated with Peutz–Jeghers syndrome. The study highlights RNA‐Seq as a useful supplement in hereditary cancer predisposition testing.

Intestinal intussusception in Peutz Jeghers syndrome: A case report

Hamartomatous polyposis is a rare cause of intussusception in adults. But this complication is the most frequent for patient with Peutz Jeghers syndrome. Small bowel screening is recommended for those patients in order to prevent emergency repetitive surgeries. We report here the case of a 20-year-old patient with confirmed Peutz Jeghers syndrome since eight years for whom a scheduled laparotomy was indicated. Asymptomatic intestinal intussusception was discovered intraoperatively. The patient was treated successfully with enterectomy and side to side anastomosis. Postoperative course was uneventful. Regular assessment as recommended for those patients is performed. Gastrointestinal intussusception in adults is rare and is often diagnosed preoperatively in a context of bowel obstruction. In the case of our patient, intussusception was diagnosed intraoperatively. This fact confirms the necessity of well-timed polypectomy in order to prevent this complication and the risk of extended resection in patients who are exposed to short gut syndrome by requiring iterative resections.

Genetics of breast cancer: management strategies and risk-reducing surgery

The last two decades have witnessed major advances in genetic sequencing which have led to more accurate identification of women at risk of developing breast cancer and calculating the associated cancer risk. This review discusses the current genetic mutations conferring risk of developing breast cancer and the management pathway for these women with identifiable mutations as well as those with a strong family history for breast cancer. Management of these individuals is complex and should involve a multidisciplinary team with interest and expertise in breast cancer genetics. There are several treatment options ranging from surveillance to risk-reducing surgery. Risk reduction surgery has been popularised by celebrities who are carriers of breast cancer genes, and raised public awareness of breast cancer genetics and associated risk.

Primary experience of small bowel polypectomy with balloon-assisted enteroscopy in young pediatric Peutz-Jeghers syndrome patients

For Peutz-Jeghers syndrome (PJS) patients, small bowel polyps develop and result in symptoms at an early age. Balloon-assisted enteroscopy (BAE) is verified as a safe and efficient choice to evaluate and remove small intestinal polyps in adult PJS. But the safety of BAE, especially BAE-facilitated polypectomy for young pediatrics, is little known. This prospective study focused on the effectiveness and safety of BAE-facilitated polypectomy in small bowel for young pediatric PJS. PJS patients (aged 0-14 years old) with BAE (including both single-balloon and double-balloon enteroscopies) were included from 1 September 2012 to 30 April 2018. The demographic data, medical history, and details of BAE were recorded. BAE-related complications and symptom relief after BAE were evaluated and compared between the PJS patients aged 5-10 years old (the younger pediatric group) and those aged 11-14 years old (the older pediatric group). A total of 41 pediatric PJS patients (5-14 years old) subjected to 82 BAEs were included. BAE-facilitated polypectomy was performed for 33 children (80.5%), and 242 polyps in small bowel were removed. For 10 (24.4%) patients, one or more giant polyps (maximum diameter larger than 5 cm) were removed. For eight patients, no polypectomy was done as no polyps were observed (six subjects) or not suitable for BAE-facilitated polypectomy (two subjects) because of high risk of perforation. The complication rates of BAE and BAE-facilitated polypectomy were 1.2% (1/82) and 1.8% (1/55), and the symptom relief rate was 70.8% (17/24). Compared with the older pediatric group, the younger pediatric group showed no increased BAE complication rate (0.0% vs. 5.0%, p = 0.488) and a comparable rate of symptom relief after BAE therapy (80.8% vs. 55.6%, p = 0.356).Conclusion: BAE-facilitated polypectomy in young pediatric PJS is safe and effective.What is known:• Small bowel evaluation and prophetic polypectomy are important for pediatric PJS patients to avoid polyp-related intussusception, obstruction, and bleeding.• BAE polypectomy was a recommended intervention for removing small bowel polyps in adult PJS patients.What is new:• BAE-facilitated small bowel polypectomy is safe and effective for young pediatric PJS, even for those aged less than 10 years old.

Hereditary and Sporadic Pancreatic Ductal Adenocarcinoma: Current Update on Genetics and Imaging

Pancreatic ductal adenocarcinoma (PDAC) is a genetically heterogeneous, biologically aggressive malignancy with a uniformly poor prognosis. While most pancreatic cancers arise sporadically, a small subset of PDACs develop in patients with hereditary and familial predisposition. Detailed studies of the rare hereditary syndromes have led to identification of specific genetic abnormalities that contribute to malignancy. For example, germline mutations involving BRCA1, BRCA2, PRSS1, and mismatch repair genes predispose patients to PDAC. While patients with Lynch syndrome develop a rare "medullary" variant of adenocarcinoma, intraductal papillary mucinous tumors are observed in patients with McCune-Albright syndrome. It is now well established that PDACs originate via a multistep progression from microscopic and macroscopic precursors due to cumulative genetic abnormalities. Improved knowledge of tumor genetics and oncologic pathways has contributed to a better understanding of tumor biology with attendant implications on diagnosis, management, and prognosis. In this article, the genetic landscape of PDAC and its precursors will be described, the hereditary syndromes that predispose to PDAC will be reviewed, and the current role of imaging in screening and staging assessment, as well as the potential role of molecular tumor-targeted imaging for evaluation of patients with PDAC and its precursors, will be discussed. Keywords: Abdomen/GI, Genetic Defects, Oncology, Pancreas Supplemental material is available for this article. © RSNA, 2020.

The paradox of cancer genes in non-malignant conditions: implications for precision medicine

Next-generation sequencing has enabled patient selection for targeted drugs, some of which have shown remarkable efficacy in cancers that have the cognate molecular signatures. Intriguingly, rapidly emerging data indicate that altered genes representing oncogenic drivers can also be found in sporadic non-malignant conditions, some of which have negligible and/or low potential for transformation to cancer. For instance, activating KRAS mutations are discerned in endometriosis and in brain arteriovenous malformations, inactivating TP53 tumor suppressor mutations in rheumatoid arthritis synovium, and AKT, MAPK, and AMPK pathway gene alterations in the brains of Alzheimer's disease patients. Furthermore, these types of alterations may also characterize hereditary conditions that result in diverse disabilities and that are associated with a range of lifetime susceptibility to the development of cancer, varying from near universal to no elevated risk. Very recently, the repurposing of targeted cancer drugs for non-malignant conditions that are associated with these genomic alterations has yielded therapeutic successes. For instance, the phenotypic manifestations of CLOVES syndrome, which is characterized by tissue overgrowth and complex vascular anomalies that result from the activation of PIK3CA mutations, can be ameliorated by the PIK3CA inhibitor alpelisib, which was developed and approved for breast cancer. In this review, we discuss the profound implications of finding molecular alterations in non-malignant conditions that are indistinguishable from those driving cancers, with respect to our understanding of the genomic basis of medicine, the potential confounding effects in early cancer detection that relies on sensitive blood tests for oncogenic mutations, and the possibility of reverse repurposing drugs that are used in oncology in order to ameliorate non-malignant illnesses and/or to prevent the emergence of cancer.

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.

Peutz-Jeghers syndrome with mesenteric fibromatosis: A case report and review of literature

BACKGROUND

Peutz-Jeghers syndrome (PJS) and mesenteric fibromatosis (MF) are rare diseases, and PJS accompanying MF has not been previously reported. Here, we report a case of a 36-year-old man with both PJS and MF, who underwent total colectomy and MF surgical excision without regular follow-up. Two years later, he sought treatment for recurrent acute abdominal pain. Emergency computed tomography showed multiple soft tissue masses in the abdominal and pelvic cavity, and adhesions in the small bowel and peritoneum. Partial intestinal resection and excision of the recurrent MF were performed to relieve the symptoms.

CASE SUMMARY

A 36-year-old male patient underwent total colectomy for PJS with MF. No regular reexamination was performed after the operation. Two years later, due to intestinal obstruction caused by MF enveloping part of the small intestine and peritoneum, the patient came to our hospital for treatment. Extensive recurrence was observed in the abdomen and pelvic cavity. The MF had invaded the small intestine and could not be relieved intraoperatively. Finally, partial bowel resection, proximal stoma, and intravenous nutrition were performed to maintain life.

CONCLUSION

Regular detection is the primary way to prevent deterioration from PJS. Although MF is a benign tumor, it has characteristics of invasive growth and ready recurrence. Therefore, close follow-up of both the history of MF and gastrointestinal surgery are advisable. Early detection and early treatment are the main means of improving patient prognosis.

Familial Pancreatic Cancer: Current Perspectives

Pancreatic cancer (PC) is a highly lethal disease, mostly incurable when detected. Thus, despite advances in PC treatments, only around 7% of patients survive 5-years after diagnosis. This morbid outcome is secondary to multifactorial reasons, such as late-stage diagnosis, rapid progression and minimal response to chemotherapy. Based on these factors, it is of special relevance to identify PC high-risk individuals in order to establish preventive and early detection measures. Although most PC are sporadic, approximately 10% cases have a familial basis. No main causative gene of PC has been identified but several known germline pathogenic mutations are related with an increased risk of this tumor. These inherited cancer syndromes represent 3% of all PC. On the other hand, in 7% of cases of PC, there is a strong family history without a causative germline mutation, a situation known as familial pancreatic cancer (FPC). In recent years, there is increasing evidence supporting the benefit of genetic germline analysis in PC patients, and periodic pancreatic screening in PC high-risk patients (mainly those with a lifetime risk greater than 5%), although there is no general agreement in the group of patients and individuals to study and screen. In the present review, we expose an update in the field of hereditary and FPC, with the aim of describing the current strategies and implications in genetic counseling, surveillance and therapeutic interventions.

Complete histopathologic examination of risk reduction gastrectomy specimens for CDH1 germline mutation: Is it warranted in routine clinical practice?

AIMS

CDH1 germline mutation is associated with high penetrance of hereditary diffuse gastric cancer (HDGC). Due to the lack of endoscopically identifiable lesions, routine surveillance is ineffective in the early detection of gastric cancer, and risk-reduction gastrectomy is often recommended. Many academic pathology departments elect to submit the entire gastrectomy specimen for histological examination, which is associated with significantly increased cost, technical and professional time, and turnaround time.

METHODS

We present our experience with 5 completely submitted and 2 representatively submitted prophylactic total gastrectomy cases in HDGC patients.

RESULTS

Multifocal intramucosal signet ring cell carcinoma was identified in all cases except one, in which only in situ carcinoma was identified. The tumoral foci (2 to 35 per case; average 14.4) were concentrated in proximal stomach. No submucosal invasion or nodal metastases was seen in any case. The final stage was either stage 0 (pTisN0cM0) or stage 1a (pT1aN0cM0).

CONCLUSIONS

Our findings are in line with that reported in the literature. Considering that deeply invasive carcinoma is very rare in this situation, and no further treatment is indicated for the vast majority of those patients, complete submission and pathologic examination of the entire stomach provides little additional value for routine clinical management. We propose a two-step approach with targeted submission of the proximal stomach, and subsequent entire submission of the remaining stomach if no intramucosal carcinoma is identified during the initial targeted examination.

Colon cancer of Peutz-Jeghers syndrome with gallolyticus endocarditis

We report a case of Peutz-Jeghers syndrome with gallolyticus endocarditis which has not yet been reported. Colon cancer was observed and implicated in Peutz-Jeghers syndrome. A 44-year-old female with fever and heart murmur was diagnosed as infective endocarditis caused by streptococcus gallolyticus. After treatment with antibiotics and mitral valbuloplasty, we performed gastrointestinal endoscopic studies and found polyps in stomach and colon. Histological findings of a large pedunculated colon polyp revealed hamartomatous polyp with a lesion of adenocarcinoma with adenoma. She had pigmentation of digits. Her father had also digits pigmentation and died of pancreas cancer. Peutz-Jeghers syndrome with colon cancer was incidentally diagnosed by infective endocarditis and subsequent colonoscopy.

Prediction of Deleterious Non-synonymous SNPs of Human STK11 Gene by Combining Algorithms, Molecular Docking, and Molecular Dynamics Simulation

Serine-threonine kinase11 (STK11) is a tumor suppressor gene which plays a key role in regulating cell growth and apoptosis. It is widely known as a multitasking kinase and engaged in cell polarity, cell cycle arrest, chromatin remodeling, energy metabolism, and Wnt signaling. The substitutions of single amino acids in highly conserved regions of the STK11 protein are associated with Peutz-Jeghers syndrome (PJS), which is an autosomal dominant inherited disorder. The abnormal function of the STK11 protein is still not well understood. In this study, we classified disease susceptible single nucleotide polymorphisms (SNPs) in STK11 by using different computational algorithms. We identified the deleterious nsSNPs, constructed mutant protein structures, and evaluated the impact of mutation by employing molecular docking and molecular dynamics analysis. Our results show that W239R and W308C variants are likely to be highly deleterious mutations found in the catalytic kinase domain, which may destabilize structure and disrupt the activation of the STK11 protein as well as reduce its catalytic efficiency. The W239R mutant is likely to have a greater impact on destabilizing the protein structure compared to the W308C mutant. In conclusion, these mutants can help to further realize the large pool of disease susceptibilities linked with catalytic kinase domain activation of STK11 and assist to develop an effective drug for associated diseases.