Peutz-Jeghers syndrome

Peutz-Jeghers Syndrome: A Comprehensive Review of Genetics, Clinical Features, and Management Approaches

A relatively rare inherited condition known as Peutz-Jeghers syndrome (PJS) causes mucocutaneous pigmentation and gastrointestinal hamartomatous polyps. These polyps are non-cancerous, but the presence of PJS significantly increases the chances of developing various types of cancers, such as colorectal, pancreatic, gastric, and breast cancer. The purpose of this review article is to give an abbreviated summary of what is currently known about this syndrome, covering its clinical symptoms, pathophysiology, genetics, and management. PJS also raises the risk of getting many malignancies, especially gastrointestinal and pelvic cancers. Symptoms of the gastrointestinal tract brought on by hamartomatous polyps are frequent and include stool blockage, bleeding, and stomach pain. The pigmentation commonly appears as prominent bluish-black macules and frequently affects the skin and mucous membranes. Small macules and large regions of lentiginous pigmentation are both possible. Numerous areas, including the perioral area, buccal mucosa, fingers, and lips, exhibit pigmentation. Bowel obstruction and intussusception risk can be decreased by early identification and routine surveillance of gastrointestinal polyps. The gene serine/threonine kinase 11 (STK11) controls several biological functions, including cell polarity, growth, and proliferation. Genetic counseling is recommended for the affected individuals and their families. This can help assess the risk of passing on the condition to future generations and provide information about available reproductive options. Regular surveillance is crucial for managing the syndrome and reducing the risk of cancer development. Other syndromes and extra-gastrointestinal characteristics, such as somatic tumor polyps outside the gastrointestinal tract, are also linked to this syndrome.

Case Report: Duodenal Carcinoma in a 40-Year-Old Asian Man With Cowden Syndrome

Introduction

Cowden syndrome is a rare autosomal dominant genetic disease associated with PTEN mutation and is mainly shown as systemic multisystem lesions. The incidence of adenocarcinoma of the duodenum with Cowden syndrome in Asian males is rare. We hereby describe the diagnosis, treatment, and prognosis of a patient with duodenal carcinoma and Cowden syndrome.

Case Description

A 40-year-old Chinese man was hospitalized because of gastrointestinal hemorrhage and anemia due to infiltrating adenocarcinoma of the descending part of the duodenum. He also had typical signs of Cowden syndrome, such as multiple polyps of the gastrointestinal tract, macrocephaly, papilloma of the tongue, soles hyperkeratosis, and melanosis spots. After the pancreaticoduodenectomy (classic Whipple), the lesions revealed the presence of hamartomatoid polyps, and some of them mutated into non-mucinous adenocarcinoma (80%) and mucinous adenocarcinoma (20%). Further investigation showed a lack of PTEN protein expression in the duodenal neoplasm, and genetic analysis showed the mutation of p.E242fs in PTEN. The patient was followed up for 1 year. There was no appearance of recurrence or distant metastasis.

Conclusion

It is suggested that we should pay more attention to the differential diagnosis of duodenal carcinoma combined with gastrointestinal polyps. If multiple gastrointestinal polyps with gastrointestinal bleeding are encountered, Cowden syndrome should be considered, and timely diagnosis and treatment should be implemented.

Imaging of the small bowel: a review of current practice

This article summarises radiological imaging of the small bowel, with an emphasis on Crohn's disease. Different imaging techniques are discussed, including the advantages and disadvantages of each modality, and radiological findings for common small bowel pathologies are described, supplemented with pictorial examples.

Multidetector CT enterography of focal small bowel lesions: a radiological-pathological correlation

Focal small bowel lesions present a diagnostic challenge for both the radiologist and gastroenterologist. Both the detection and characterization of small bowel masses have greatly improved with the advent of multidetector CT enterography (MD-CTE). As such, MD-CTE is increasingly utilized in the workup of occult gastrointestinal bleeding. In this article, we review the spectrum of focal small bowel masses with pathologic correlation. Adenocarcinoma, the most common primary small bowel malignancy, presents as a focal irregular mass occasionally with circumferential extension leading to obstruction. Small bowel carcinoid tumors most commonly arise in the ileum and are characterized by avid enhancement and marked desmoplastic response of metastatic lesions. Aneurysmal dilatation of small bowel is pathognomonic for lymphoma and secondary findings of lymphadenopathy and splenomegaly should be sought. Benign small bowel masses such as leiomyoma and adenoma may be responsible for occult gastrointestinal bleeding. However, primary vascular lesions of the small bowel remain the most common cause for occult small bowel gastrointestinal bleeding. The arterial phase of contrast obtained with CTE aids in recognition of the vascular nature of these lesions. Systemic conditions such as Peutz-Jeghers syndrome and Crohn's disease may be suggested by the presence of multiple small bowel lesions. Lastly, potential pitfalls such as ingested material should be considered when faced with focal small bowel masses.

Clinics in diagnostic imaging. 159. Jejunal intussusception due to Peutz-Jeghers syndrome

A 21-year-old woman presented with acute onset of upper abdominal pain. A diagnosis of Peutz-Jeghers syndrome (PJS) was made based on the clinical picture of perioral pigmentation with imaging findings of transient jejunojejunal intussusceptions and small bowel polyps, and confirmed by characteristic histopathological appearances of Peutz-Jeghers polyps. PJS is a rare hereditary condition characterised by unique hamartomatous polyps, perioral mucocutaneous pigmentations, and increased susceptibility to gastrointestinal and extraintestinal neoplasms. Patients usually present with recurrent abdominal pain due to intussusception caused by polyps. Other modes of presentations include rectal bleeding and melaena. We describe the imaging findings of PJS and provide a brief review of bowel polyposis syndromes. The latter are relatively rare disorders characterised by multiple polyps in the large or small intestine, with associated risk of malignancies and other extraintestinal manifestations. Awareness of the manifestations and early diagnosis of these syndromes is crucial to prevent further complications.

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.

Small bowel intussusception in a pregnant woman with Peutz-Jeghers Syndrome

Intussusception is the most frequent complication of Peutz-Jeghers Syndrome (PJS), but usually seen in child age. It is a predictable, but infrequent complication in adults with PJS. However, there is no report about intussusception in pregnancy period secondary to Peutz-Jeghers (PJ) polyps in the literature. In this paper, we present a rare intussusception case in a pregnant woman with PJS, which was diagnosed with magnetic resonance imaging, and discuss this condition with a brief literature review.

Findings from the Peutz-Jeghers syndrome registry of uruguay

Background

Peutz-Jeghers syndrome (PJS) is characterized by intestinal polyposis, mucocutaneous pigmentation and an increased cancer risk, usually caused by mutations of the STK11 gene. This study collected epidemiological, clinical and genetic data from all Uruguayan PJS patients.

Methods

Clinical data were obtained from public and private medical centers and updated annually. Sequencing of the STK11 gene in one member of each family was performed.

Results and discussion

25 cases in 11 unrelated families were registered (15 males, 10 females). The average age of diagnosis and death was 18 and 41 years respectively. All patients had characteristic PJS pigmentation and gastrointestinal polyps. 72% required urgent surgery due to intestinal obstruction. 3 families had multiple cases of seizure disorder, representing 20% of cases. 28% developed cancer and two patients had more than one cancer. An STK11 mutation was found in 8 of the 9 families analyzed. A unique M136K missense mutation was noted in one family. Comparing annual live births and PJS birth records from 1970 to 2009 yielded an incidence of 1 in 155,000.

Conclusion

The Uruguayan Registry for Peutz-Jeghers patients showed a high chance of emergent surgery, epilepsy, cancer and shortened life expectancy. The M136K missense mutation is a newly reported STK 11 mutation.

Unusual presentation of intussusception of the small bowel with peutz jeghers syndrome: report of a case

The Peutz Jeghers syndrome (PJS) is an autosomal dominant disorder which is characterised by hamartomatous polyposes of the gastrointestinal tract, melanin pigmentation of the skin and mucous membranes, and an increased risk for cancer. We are reporting a case of a 15-year-old male with Peutz Jeghers syndrome, who presented to us with features of chronic intestinal obstruction and anaemia. Initially, patient was managed conservatively, but later on, an elective exploratory laparotomy was done for definitive management of intussusception. Laparotomy revealed a jejuno-jejunal intussusception with spontaneous recanalisation of gut which contained a long segment of gangrenous small bowel in the lumen. Resection and anastomosis of the jejunal segment was done. To the best of our knowledge, this might be the first case report on spontaneous recanalisation of small intestine.

Hereditary gynecological tumors associated with Peutz-Jeghers syndrome (Review)

Peutz-Jeghers syndrome (PJS) is an autosomal dominant disease that is characterized by gastrointestinal hamartomatous polyposis and mucocutaneous melanin spots. The tumor suppressor gene, STK11/LKB1, which is located on chromosome 19p13.3, has been reported to be responsible for this condition. PJS is complicated by benign and malignant tumors of various organs and complications from rare diseases, including sex cord tumor with annular tubules (SCTAT) and minimal deviation adenocarcinoma (MDA), which have also recently attracted attention in the field of gynecology. Among the total MDA cases, 10% are complications of PJS, and mutations in the STK11 gene are closely associated with the development and prognosis of MDA. Furthermore, a new type of uterine cervical tumor, lobular endocervical glandular hyperplasia (LEGH), has been identified and has been predicted to be a precancerous lesion of MDA. The first case of LEGH induced by a germline STK11 mutation has also been described. A high risk of endometrial cancer in PJS has also been reported. These developments suggest that PJS is an important syndrome of hereditary gynecological tumors that requires further study.

Acute malignant intestinal obstruction accompanied by synchronous multifocal intestinal cancer in Peutz-Jeghers syndrome: report of a case

Acute mechanical intestinal obstruction is one of the most common modes of presentation in patients with Peutz-Jeghers syndrome (PJS). This report presents a case of PJS with malignant acute jejunal obstruction accompanied by synchronous foci of duodenal, jejunal, and ileal cancer originated from hamartomatous polyps. The follow-up endoscopic findings of the patient also revealed severe polyposis of the entire gastrointestinal tract, including the stomach and colon, in addition to the small intestine. Very few cases of multifocal synchronous small intestinal cancer in PJS patients have been reported in the previous literature.

Duodenojejunal intussusception in Peutz-Jeghers syndrome: Report of a case

Recurrent intussusception is one of the common modes of presentation in patients with Peutz-Jeghers syndrome. This report presents a case of Peutz-Jeghers syndrome with synchronous duodenojejunal and jejunojejunal intussusceptions due to hamartomatous polyps. Very few cases of duodenojejunal intussusception in Peutz-Jeghers syndrome patients have so far been reported in the literature.

Melaena with Peutz-Jeghers syndrome: a case report

Introduction

Peutz-Jeghers syndrome (PJS) is a rare familial disorder characterised by mucocutaneous pigmentation, gastrointestinal and extragastrointestinal hamartomatous polyps and an increased risk of malignancy. Peutz-Jeghers polyps in the bowel may result in intussusception. This complication usually manifests with abdominal pain and signs of intestinal obstruction.

Case Presentation

We report the case of a 24-year-old Caucasian male who presented with melaena. Pigmentation of the buccal mucosa was noted but he was pain-free and examination of the abdomen was unremarkable. Upper gastrointestinal endoscopy revealed multiple polyps. An urgent abdominal computed tomography (CT) scan revealed multiple small bowel intussusceptions. Laparotomy was undertaken on our patient, reducing the intussusceptions and removing the polyps by enterotomies. Bowel resection was not needed.

Conclusion

Melaena in PJS needs to be urgently investigated through a CT scan even in the absence of abdominal pain and when clinical examination of the abdomen shows normal findings. Although rare, the underlying cause could be intussusception, which if missed could result in grave consequences.

[A case of Peutz-Jeghers syndrome with intraductal papillary mucinous carcinoma of pancreas]

Peutz-Jeghers syndrome (PJS), which is characterized by multiple hamartomatous polyps of the gastrointestinal tract and mucocutaneous pigmentation, is a rare autosomal dominant disease. This syndrome is often represented as a surgical emergency with complications of the polyps such as intussusception, small bowel obstruction, bleeding, and volvulus. In particular, many studies have reported that patients with this syndrome have a high risk of gastrointestinal or extragastrointestinal malignancy including gastric, duodenal, jejunal, ileal, and colonic carcinoma as well as malignancies involving other organs such as the gallbladder, biliary tract, pancreas, tonsils, breast, and reproductive system. However, there are few reported cases of an association of this syndrome with extraintestinal malignancy. In addition to that, there is no reported case of this syndrome with malignant tumor or intraductal papillary mucinous tumor of pancreas in Korea. We experienced a case of PJS accompanying intraductal papillary mucinous carcinoma of the pancreas, therefore we report this case with literatures reviewed.

Obesity related hyperinsulinaemia and hyperglycaemia and cancer development

Excess body weight in combination with physical inactivity is a major determinant for the development of insulin resistance with associated hyperglycaemia and hyperinsulinaemia and further leads to tumour development. Several prospective epidemiological studies have shown a direct association between excess weight and common malignancies, such as colon, breast (post-menopausal), endometrial, gallbladder, pancreatic, kidney and oesophageal cancers, but also less frequent malignancies, such as leukaemia, multiple myeloma and non-Hodgkin lymphoma. Insulin resistance and hyperinsulinaemia are certainly key biological mechanisms underlying the relationship between adiposity and tumour development. The anti-diabetic drug, metformin, in addition to reduction of insulin resistance has also shown anti-tumour properties, and is increasingly being considered as a drug to prevent and treat obesity-related cancers. Several biological pathways have been involved in the association between excess body weight, insulin resistance and cancer, such as chronic low-grade inflammation, glucose toxicity, AGE product metabolism and the adenosine monophosphate kinase pathway.

Suppression of Peutz-Jeghers polyposis by targeting mammalian target of rapamycin signaling

PURPOSE

Peutz-Jeghers syndrome (PJS) is a unique disorder characterized by the development of hamartomas in the gastrointestinal tract as well as increased risks for variety of malignancies. Germ-line mutations of LKB1 cause PJS. We have generated Lkb1+/- mice, which model human PJS. Rapamycin and its analogues are promising preventive and therapeutic agents that specifically inhibit signaling from mammalian target of rapamycin (mTOR). Hyperactivation of mTOR signaling has been associated with PJS. The objective of the study is to investigate the efficacy of mTOR inhibition in suppressing Peutz-Jeghers polyposis in Lkb1+/- mice.

EXPERIMENTAL DESIGN

We initiated a trial of rapamycin in Lkb1+/- mice at 9 months of age (after the onset of polyposis) at the dose of 2 mg/kg/d for a 2-month period. We assessed the efficacy of rapamycin by measuring polyp sizes and tumor burden. To examine the effect of rapamycin on mTOR signaling, phosphorylation levels of S6 were evaluated by immunostaining.

RESULTS

We observed a significant decrease in mean tumor burden (Student's t test, P = 0.023) as well as total tumor burden in rapamycin-treated group compared with control group. Comparison of the polyp size observed in both rapamycin-treated and control groups showed that rapamycin efficiently decreased the tumor burden of large polyps (> 8 mm). This inhibition of rapamycin was associated with a decrease in phosphorylated S6 levels in the polyps.

CONCLUSIONS

Rapamycin effectively suppresses Peutz-Jeghers polyposis in a mouse model, suggesting that rapamycin or its analogues may represent a new targeted therapy for the treatment of PJS.

Pathology of the hereditary colorectal carcinoma

Positive familial history (first or second degree relative) for colorectal carcinoma (CRC) can be found in approximately 30% of all newly diagnosed cases, but less than 5% will be due to a defined genetic category of hereditary CRC. Pathologic examination of the biopsy or resection specimen can help in identification of unsuspected cases of certain forms of hereditary CRC due to the characteristic morphologic findings. Additional immunohistochemical and molecular studies can then provide a definitive diagnosis. The most common form of hereditary CRC is Lynch syndrome (hereditary non-polyposis colorectal cancer, HNPCC) which is characterized by proximally located tumors frequently showing mucinous and medullary type histologic features. The syndrome results from a germline mutation in genes for mismatch repair (MMR) proteins leading to insufficient DNA repair and development of tumors characterized by high levels of instability in short tandem repeat DNA sequences (microsatellites) or "microsatellite instability-high" (MSI-H). The presence of intra-epithelial lymphocytes is single most helpful morphologic feature in identification of CRC caused by deficiency in MMR proteins, for which MSI-H status is a good marker but morphologic features and MSI-H do not differentiate tumors caused by germline mutations in one of the MMR genes (Lynch syndrome) from sporadic CRC due to inactivation of MLH-1 through promoter methylation. Hereditary CRC may also arise in various familial polyposis syndromes which include familial adenomatous polyposis (FAP), attenuated FAP and other multiple adenomas syndromes as well as various hamartomatous polyposis syndromes. All of these rare conditions have characteristic clinical presentation and histopathologic features of polyps and most of them have defined genetic abnormality. Furthermore, due to the germline nature of mutations in these syndromes, various extracolonic manifestations may be the first sign of the disease and knowledge of such associations can greatly improve the quality of care for these patients. The role of pathologist is to recognize these characteristics and initiate appropriate follow up with clinicians and genetic counselors.

The diagnostic role of abdominal CT imaging findings in adults intussusception: focused on the vascular compromise

Intussusception is defined as telescoping of one segment of the gastrointestinal tract into an adjacent one. Unlike that in children, adult intussusception is a relatively rare condition. More than 90% of patients with adult intussusception have been reported to have an organic cause, with benign or malignant tumors for accounting for approximately 65% of the cases. In general, the diagnosis is easily made by means of computed tomography (CT) or magnetic resonance (MR) imaging. The imaging appearance of a bowel-within-bowel configuration with or without contained fat and mesenteric vessels, is pathognomonic. As the intussusceptum enters into the intussuscipiens, the mesentery is carried forward and trapped between the overlapping layers of bowel. The twisting or severe constriction of the mesenteric vessels may result in vascular compromise with subsequent edematous thickening of the involved bowel. In these circumstances, ischemic necrosis may develop if timely intervention is not undertaken. Therefore, determination of the presence or absence of intestinal necrosis in intussusception is important in patient management. On CT, the presence of well-known diagnostic CT criteria for strangulated obstruction (especially severe engorgement or twisting of the mesenteric vessels) as well as evidence of loss of the layered pattern, accumulation of extraluminal fluid collection, and bowel perforation, may suggest the diagnosis of intestinal necrosis. CT and MR imaging are limited in determining the primary disease causing intussusception. However, CT and MR provide excellent pre-operative evaluation, including the possible extension and/or dissemination of a malignant tumor. CT and MR imaging may also be useful in suggesting the presence of vascular compromise.

Avances en radiología del intestino delgado: enteroclisis por tomografía computarizada

Computed tomography (CT) enteroclysis is a new technique consisting of helical CT of the abdomen and pelvis after administration of water through a nasojejunal tube and intravenous contrast, resulting in adequate distension and visualization of the small bowel wall. The use of this technique is especially recommended in patients with gastrointestinal bleeding of unknown etiology, possible neoplastic processes of the small bowel, partial small bowel obstruction, and inflammatory bowel disease. One-hundred consecutive patients underwent CT enteroclysis (multiple detectors; 8, 16, or 64) over a 1-year period for suspected lesions of the small bowel. Of these, 31 were positive: Crohn's disease (17), tumors (8), partial obstruction (2), radiation enteritis (1), sprue (1), pneumatosis cystoids (1), and dilatation of bowel loops (1). In 28 of the 31 patients, the findings were confirmed by pathology, endoscopy or clinical follow-up.

Eponyms in Radiology of the Digestive Tract: Historical Perspectives and Imaging Appearances

Eponyms are a means of honoring individuals who have made lasting contributions to medicine. Eponyms are frequently encountered in the field of radiology, especially radiology of the digestive tract. However, the use of eponyms may fail to convey a precise meaning or definition and could result in miscommunication. Furthermore, in some instances, more than one individual may have contributed to the discovery or description of a particular structure or disease, whereas in others, an eponym may have been incorrectly applied and then propagated for years thereafter in the medical literature. Still, eponyms are a means of honoring those who have made important discoveries and observations, and familiarity with these terms is important for proper reporting and accurate communication. Moreover, the acquisition of some historical knowledge about the individuals whose names are associated with various structures or diseases helps restore some humanity to the science of medicine.

The hamartomatous polyposis syndromes: a clinical and molecular review

Inherited forms of gastrointestinal cancer have been a major focus of study and advancement over the past decade. Familial adenomatous polyposis and hereditary nonpolyposis colon cancer are the two most common heritable colon cancer syndromes. Inherited polyposis syndromes are characterized by the dominant type of polyp (whether adenomatous or hamartomatous) present and by the polyp's location within the gastrointestinal tract. The hamartomatous polyposis syndromes are characterized by an overgrowth of cells native to the area in which they normally occur. They represent a small but appreciable number of the gastrointestinal inherited cancer predisposition syndromes; it is now known that many of these syndromes carry a substantial risk for developing colon cancer as well as other gastrointestinal and pancreatic cancers. Patients afflicted with these syndromes are also at significant risk for extraintestinal malignancies. Seven inherited hamartomatous polyposis syndromes have been described: familial juvenile polyposis syndrome, Cowden's syndrome, Bannayan-Ruvalcaba-Riley syndrome, Peutz-Jeghers syndrome, basal cell nevus syndrome, neurofibromatosis 1, and multiple endocrine neoplasia syndrome 2B. Hereditary mixed polyposis syndrome is a variant of juvenile polyposis characterized by both hamartomatous and adenomatous polyps. The hamartomatous syndromes occur at approximately 1/10th the frequency of the adenomatous syndromes and account for <1% of colorectal cancer in Northern America. While the diagnosis of these inherited syndromes is primarily clinical, genetic testing is now available for all six syndromes. However, there are a significant number of spontaneous mutations seen in each of the syndromes. The management of these patients necessitates a coordinated multidisciplinary approach. The purpose of this review is to characterize the clinical and pathological features of these syndromes and to review the targets of cancer surveillance. The molecular alterations responsible for the inherited hamartomatous polyposis syndromes will also be discussed.

Radiological work-up in Peutz-Jeghers syndrome

BACKGROUND

The development of modern imaging studies such as high-resolution US and various MR imaging sequences have enabled their application to the examination of the gastrointestinal tract. OBJECTIVE. To compare radiological contrast studies, US and MRI in patients with Peutz-Jeghers syndrome (PJS).

MATERIALS AND METHODS

Ten members of two families were evaluated. The patients were divided into three groups according to the presence of perioral pigmentations and current clinical symptomatology. Patients were examined using US, MRI and radiological contrast studies.

RESULTS

In the disease-free family members ( n=3), no pathological findings were found. In asymptomatic ( n=4) and symptomatic patients ( n=3), polyps were demonstrated using contrast studies in all cases. MRI demonstrated all the polyps. Ultrasound revealed the polyps in three out of six patients. In addition to the polyps, intussusceptions were shown. There was no evidence of malignant transformation on any of the studies.

CONCLUSIONS

Although PJS is a childhood or teenage disease, patients should be closely monitored during adulthood because of the development of gastrointestinal and extragastrointestinal malignancies. Contrast studies remain the gold standard. However, radiological follow-up could be undertaken by US or MRI, which would not impose a radiation burden during life-time follow-up.

CT of the duodenum: an overlooked segment gets its due

Abdominal computed tomography (CT) is frequently performed to evaluate gastrointestinal pathologic conditions, and the majority of the gastrointestinal radiology literature has concentrated on the colon, stomach, and distal small bowel. In a description of CT findings of duodenal pathologic conditions, congenital, traumatic, inflammatory, and neoplastic diseases are presented. Congenital duodenal anomalies such as duplications and diverticula are usually asymptomatic, while annular pancreas and malrotation may manifest in the 1st decade of life. CT plays a vital role in the diagnosis of traumatic duodenal injury. Primary inflammatory processes of the duodenum such as ulcers and secondary involvement from pancreatitis can reliably be diagnosed at CT. Infectious diseases of the duodenum are difficult to diagnose, as the findings are not specific. While small bowel malignancies are relatively rare, lipoma, adenoma, and adenocarcinoma, as well as local extension from adjacent malignancies, can be diagnosed at CT. Careful CT technique and attention to the duodenum can result in reliable prospective diagnoses.

Small intestinal neoplasms

Small intestinal neoplasms are uncommonly encountered in clinical practice. They may occur sporadically, in association with genetic diseases (e.g., familial adenomatous polyposis coli or Peutz-Jeghers syndrome), or in association with chronic intestinal inflammatory disorders (e.g., Crohn's disease or celiac sprue). Benign small intestinal tumors (e.g., leiomyoma, lipoma, hamartoma, or desmoid tumor) usually are asymptomatic but may present with intussusception. Primary malignancies of the small intestine-including adenocarcinoma, leiomyosarcoma, carcinoid, and lymphoma-may present with intestinal obstruction, jaundice, bleeding, or pain. Extraintestinal neoplasms may involve the intestine via contiguous spread or peritoneal metastasis. Hematogenous metastases to the intestine from an extraintestinal primary are unusual and are most typical of melanoma. Because the small intestine is relatively inaccessible to routine endoscopy, diagnosis of small intestinal neoplasms is often delayed for months after onset of symptoms. When the diagnosis is suspected, enteroclysis is the most useful imaging study. Small bowel endoscopy (enteroscopy) is increasingly widely available and may permit earlier, nonoperative diagnosis.

Peutz-Jeghers syndrome: risks of a hereditary condition

BACKGROUND

Peutz-Jeghers syndrome (PJS) is a rare autosomal-dominant disorder characterized by hamartomatous polyposis of the gastrointestinal tract and melanin pigmentation of the skin and mucous membranes. We review the clinical features of PJS with special emphasis on the risks for its gene carriers.

METHODS

Review of the literature.

RESULTS

Risks imposed by the presence of polyps in PJS patients include surgical emergencies like small bowel intussusception, and chronic or acute bleeding from the polyps. As the polyps in PJS are hamartomas, the disease had in the past always been thought not to have malignant potential. However, more and more reports suggest an association of PJS with both gastrointestinal and non-gastrointestinal tumours. Whether these malignancies originate from the polyps is not clear, but the frequent occurrence of some rare extra-intestinal malignancies such as tumours of the ovary (sex cord tumours with annular tubules), cervix (adenoma malignum) and testis (Sertoli cell tumours) indicates a general susceptibility for the development of malignancies. The PJS gene, which was recently identified to encode for the serine threonine kinase STK11, is therefore thought to act as a tumour-suppressor gene.

CONCLUSIONS

PJS gene carriers not only run risks of polyp-induced gastrointestinal complications, but also are at increased risk of developing cancer, both within and outside the gastrointestinal tract. As genetic identification of asymptomatic gene carriers in this relatively rare disorder becomes possible, surveillance and screening protocols need to be developed for PJS patients and their relatives.

STK11/LKB1 germline mutations are not identified in most Peutz-Jeghers syndrome patients

Germline mutations of the STK11 gene mapped to chromosome 19p13.3 are responsible for Peutz Jeghers syndrome (PJS), a dominant disorder associated with characteristic gastrointestinal hamartomatous polyps and a predisposition to various cancers. We conducted a detailed investigation of germline STK11 alterations by protein truncation test and genomic DNA sequence analysis in ten unrelated PJS families. We identified a novel truncating deletion spanning STK11 exons 2-7 in a single patient and several known polymorphisms. Loss of heterozygosity studies in PJS polyps of four of these patients identified an allelic deletion of D19S886 in another patient. Our results suggest that STK11 mutations account for only a proportion of PJS cases.

Colonoscopic diagnosis of lymphoid hyperplasia causing recurrent intussusception: report of a case

This paper describes a 6-year-old boy with recurrent ileocecal intussusception due to lymphoid hyperplasia in the terminal ileum, which was diagnosed preoperatively by colonoscopy. At the age of 3 years, he developed diarrhea and a tender abdominal mass. He was diagnosed as having intussusception by ultrasound and was treated by hydrostatic barium enema. After resolution, he had three recurrent episodes of intussusception. A contrast barium enema revealed a small mass in the ileocecal region. Colonoscopy showed several exaggerated folds of the terminal ileum and a biopsy showed lymphoid hyperplasia. Because the repeated intussusception seemed to have been caused by the lymphoid hyperplasia in the terminal ileum, he underwent an ileocecal resection without any subsequent recurrence. Based on the above findings, we conclude that a colonoscopy may thus be useful both for diagnosing lymphoid hyperplasia in the terminal ileum as a cause of recurrent intussusception and for deciding how to manage it.

Peutz-Jeghers syndrome: confirmation of linkage to chromosome 19p13.3 and identification of a potential second locus, on 19q13.4

Peutz-Jeghers syndrome (PJS) is an autosomal dominant disease with variable expression and incomplete penetrance, characterized by mucocutaneous pigmentation and hamartomatous polyposis. Patients with PJS have increased frequency of gastrointestinal and extraintestinal malignancies (ovaries, testes, and breast). In order to map the locus (or loci) associated with PJS, we performed a genomewide linkage analysis, using DNA polymorphisms in six families (two from Spain, two from India, one from the United States, and one from Portugal) comprising a total of 93 individuals, including 39 affected and 48 unaffected individuals and 6 individuals with unknown status. During this study, localization of a PJS gene to 19p13.3 (around marker D19S886) had been reported elsewhere. For our families, marker D19S886 yielded a maximum LOD score of 4.74 at a recombination fraction (theta) of .045; multipoint linkage analysis resulted in a LOD score of 7.51 for the interval between D19S886 and 19 pter. However, markers on 19q13.4 also showed significant evidence for linkage. For example, D19S880 resulted in a maximum LOD score of 3.8 at theta = .13. Most of this positive linkage was contributed by a single family, PJS07. These results confirm the mapping of a common PJS locus on 19p13.3 but also suggest the existence, in a minority of families, of a potential second PJS locus, on 19q13.4. Positional cloning and characterization of the PJS mutations will clarify the genetics of the syndrome and the implication of the gene(s) in the predisposition to neoplasias.

Biliary obstruction due to duodenojejunal intussusception in Peutz-Jeghers syndrome

We report a 58-year-old woman with Peutz-Jeghers syndrome and episodic abdominal pain over a period of 30 years, possibly due to recurrent duodenojejunal intussusception, which eventually led to complete duodenal and biliary obstruction and associated mesothelioma.

Inherited breast cancer

Five to ten percent of breast cancer is attributable to the autosomal dominant inheritance of a high-risk susceptibility gene. There are a number of known inherited cancer syndromes that confer a higher risk of breast cancer. Recently, the BRCA1 gene, which is responsible for 45% of hereditary early-onset breast cancer and for the majority of co-inheritance of breast and ovarian cancer, has been cloned. Another gene that confers an increased risk of breast cancer is the BRCA2 gene, which maps to the long arm of chromosome 13 by linkage analysis. Mutations in BRCA2 account for approximately 40% of hereditary early-onset breast cancer. In addition, at least 7% of breast cancer may occur in women who are heterozygous for mutations in a gene for ataxia-telangiectasia, an autosomal recessive chromosome instability syndrome. Predictive testing for some predisposing conditions is possible through indirect or direct mutation testing. In this article, the genetics of breast cancer are reviewed, and practical concerns for the surgeon in counseling high-risk patients are addressed.

CT of intussusception in the pediatric patient: diagnosis and pitfalls

Intussusception in the pediatric patient may have a varied clinical presentation depending on its location, presence of lead point, intermittent occurrence, or underlying systemic disease. Computed tomography (CT) may be used at times in the evaluation of children with complicated presentations. The purpose of this investigation was to review the findings of CT images obtained in children with intussusception. Five patients with intussusception were diagnosed by CT at our institution between 1989 and 1994. An intraluminal mass was found in all patients. Intraluminal eccentrically located fat, as well as the target sign of alternating layers of high and low attenuation, was seen in most patients. In patients with a more long-standing process, fluid-distended loops, inflammation, and loss of tissue planes were seen and corresponded with necrosis and areas of nonviable bowel found at surgery. Finally, potential pitfalls with the layered or target appearance are discussed in the form of two patients who were initially felt to have intussusception at CT, but in whom the target appearance was later found to be due to other processes.

Peutz-Jeghers syndrome with osseous metaplasia of the intestinal polyps

A case of Peutz-Jeghers syndrome (PJS) with osseous metaplasia in three of 15 hamartomatous polyps of the small intestine is reported. At 35 years of age, the patient was diagnosed as having PJS by cutaneous pigmentation around the mouth and polyposis of the stomach, duodenum and intestine. Fifty-two polys of the large intestine were resected, which were characteristic of those of PJS. Three of them showed adenomatous and carcinomatous changes, but there was no osseous metaplasia in any of the resected polyps. At age 40, he had surgery under the diagnosis of intestinal obstruction. There were 15 polyps in the resected jejunum. These polyps were also characteristic of those of PJS. Additionally, three of these polyps were accompanied by osseous metaplasia. Histologically, mature bone formation and calcification were found close to the hyperplastic glands in the submucosa or in the propriate muscle. Malignant transformation was not observed. Osseous metaplasia is extremely rare in benign polyps, and it has not been reported in hamartomatous polyps of PJS to date. The knowledge of this association may be helpful in the clinical diagnosis of this benign lesion in PJS.

Intussusception, adenovirus, and children: a brief reaffirmation

Surgical specimens (n = 48) or autopsy case materials (n = 15) were studied from 63 pediatric patients (44 males and 19 females) with intussusceptions involving the ileocecal junction (38 patients [60.3%]), ileum (16 patients [25.4%]), jejunum (four patients [6.3%]), and other sites (five patients [8%]). Lymphoid hyperplasia formed the leading edge in 32 cases (51%); other lesions included Meckel diverticulum (six cases), lymphoma (four cases), adenomyomatous hamartoma (four cases), cecal duplication cyst (three cases), ectopic pancreas (two cases), congenital bowel malformation (two cases), and examples of Peutz-Jeghers polyp, lymphangioma, leiomyoma, and inflammatory fibroid polyp (one case each). In six cases there was no associated lesion. Immunohistochemical evaluation for adenovirus was performed in 16 of the 32 cases in which lymphoid hyperplasia was present, and five reactive cases were identified; characteristic intranuclear adenovirus inclusions were visible on hematoxylin-eosin-stained specimens from all five of these cases as well as in five additional cases (a total of 10 of 32 cases [31.2%]). The presence of Yersinia sp was confirmed by serology in one case having characteristic histologic findings. Fourteen deaths were attributable to consequences of intussusception; these patients were younger (median and mean ages, 5.5 and 8.6 months; age range, 1 month to 3.5 years) than the surviving patients (median and mean ages, 2.0 and 3.2 years; age range, 6 days to 14 years), but were not more likely to have evidence of adenovirus infection.

Gastric adenocarcinoma metastatic to the testes in Peutz-Jeghers syndrome

Peutz-Jeghers syndrome is associated with an increased frequency of gastrointestinal and extraintestinal malignancies. Ultrasound, CT, and MRI findings of testicular metastases from gastric adenocarcinoma in a boy with Peutz-Jeghers syndrome are presented.