Genetic features of Lynch syndrome in the Israeli population.

Diagnosis of Lynch syndrome (LS) may be complex. Knowledge of mutation spectrum and founder mutations in specific populations facilitates the diagnostic process. Aim of the study is to describe genetic features of LS in the Israeli population and report novel and founder mutations. Patients were studied at high-risk clinics. Diagnostics followed a multi-step process, including tumor testing, gene analysis and testing for founder mutations. LS was defined by positive mutation testing. We diagnosed LS in 242 subjects from 113 families coming from different ethnicities. We identified 54 different mutations; 13 of them are novel. Sixty-seven (59%) families had mutations in MSH2, 20 (18%) in MSH6, 19 (17%) in MLH1 and 7 (6%) in PMS2; 27% of the MSH2 mutations were large deletions. Seven founder mutations were detected in 61/113 (54%) families. Constitutional mismatch repair deficiency (CMMR-D) was identified in five families. Gene distribution in the Israeli population is unique, with relatively high incidence of mutations in MSH2 and MSH6. The mutation spectrum is wide; however, 54% of cases are caused by one of seven founder mutations. CMMR-D occurs in the context of founder mutations and consanguinity. These features should guide the diagnostic process, risk estimation, and genetic counseling.

Determinants of Pouch-Related Symptoms, a Common Outcome of Patients With Adenomatous Polyposis Undergoing Ileoanal Pouch Surgery.

INTRODUCTION: Total proctocolectomy with ileal pouch anal anastomosis (IPAA) is performed in patients with adenomatous polyposis syndromes (APSs). Data regarding pouch outcomes in APS are scarce. The purposes of this study were to determine the prevalence of pouch-related symptoms in patients with APS and to identify the contributing factors. METHODS: This is a prospective cohort study. Demographic, surgical, and clinical data were collected. Endoscopy was performed, and biopsies from the terminal ileum, pouch, and cuff were obtained in all patients and reviewed by a dedicated pathologist. RESULTS: Fifty-one patients with APS after IPAA were followed. Twenty patients (39.2%) had pouch-related symptoms. Single-stage IPAA had better outcomes than 2-stage IPAA: fewer daily bowel movements (42.9% vs 13.8% with ≤5 daily bowel movement, P = 0.02), more solid consistency (52.4% vs 6.9%, P < 0.001), and less abdominal pain (19% vs 48.3%, P = 0.034). Younger age at IPAA (<20) was also associated with better outcomes: fewer daily bowel movement (58.3% vs 17.9% with ≤5 daily bowel movement, P = 0.011), less watery consistency (8.3% vs 53.8%, P = 0.005), and abdominal pain (8.3% vs 43.6%, P = 0.037). Eighteen patients (35.3%) had endoscopic signs of inflammation, and 22 patients (43.1%) had histologic signs of pouchitis. However, no correlation was found between symptoms and endoscopic or histologic findings. The median pouchitis disease activity index was low (2, interquartile range 1-4) and did not correlate with clinical symptoms. DISCUSSION: Pouch-related symptoms are common in patients with APS after IPAA. One-stage IPAA and younger age at surgery are associated with better clinical outcomes. However, symptoms do not correlate well with endoscopic or histologic findings or with pouchitis disease activity index and might be attributed to a functional pouch disorder.

Randomized clinical study: Partially hydrolyzed guar gum (PHGG) versus placebo in the treatment of patients with irritable bowel syndrome.

BACKGROUND: The treatment of Irritable bowel syndrome (IBS) is still challenging. Partially hydrolyzed guar gum (PHGG) is a known prebiotic fiber. To assess the effects of PHGG on clinical symptoms of IBS patients in a prospective randomized double blind placebo-controlled study. METHODS: Suitable IBS patients were recruited into an 18-week-long study (2 weeks of run-in, 12 weeks of treatment and 4 weeks of follow-up). They were blindly randomized to receive 6 gr of PHGG or placebo. Treatment efficacy was evaluated by the Francis Severity IBS score, the IBS quality-of-life scores and scored parameters of weekly journal of symptoms. Deltas of changes between the final and baseline scores were compared between two groups. RESULTS: Of 121 patients who underwent randomization, 108 patients (49 in the PHGG group and 59 in the placebo group) had all the data needed for intention-to-treat analysis. A 12-week administration of PHGG led to a significant improvement of journal bloating score in the PHGG group versus placebo (-4.1±13.4 versus -1.2±11.9, P=0.03), as well as in bloating+gasses score (-4.3±10.4 versus -1.12±10.5, P = 0.035). The effect lasted for at least 4 weeks after the last PHGG administration. PHGG had no effect on other journal reported IBS symptoms or on Severity and Quality of life scores. There were no significant side effects associated with PHGG ingestion. The rate of dropouts was significantly higher among patients in the placebo group compared with the PHGG group (49.15% versus 22.45%, respectively, P = 0.01). CONCLUSIONS: The results of this study support the administration of 6 g/day PHGG for IBS patients with bloating. TRIAL REGISTRATION: NCT01779765.

Non-steroidal anti-inflammatory drugs and selective apoptotic anti-neoplastic drugs in the prevention of colorectal cancer: the role of super aspirins.

There is increasing evidence to suggest that aspirin and other non-steroidal anti-inflammatory drugs reduce the risk of colorectal cancer. This observation is supported by animal studies that show fewer tumors per animal and fewer animals with tumors after administration of several different NSAIDs. Intervention data in familial adenomatous polyposis have established that the effect is exerted on the process of human colonic adenoma formation. Supportive evidence in sporadic colorectal neoplasia, derived from 22 of 24 studies (both case-control and cohort), found a reduced risk in men and women for cancers of the colon and the rectum and for both aspirin and the other NSAIDs. Earlier detection of lesions as a result of drug-induced bleeding does not seem to account for these findings. Although the molecular mechanism responsible for the chemopreventive action of this class of drugs is not yet completely understood, the protection may affect several pathways including both cell cycle arrest and induction of apoptosis. In the third millennium the question is not if but how. Based on the consistency of epidemiological, clinical and experimental data, the association between regular long-term aspirin or NSAIDs intake and a decreased death rate from colorectal cancer is sound and there is no need for further placebo trials. At the same time, despite this consistency there is no clear data on the dose, duration or frequency of use for cancer-preventive activity.

[Muir-Torre syndrome and HNPCC: importance of clinical diagnosis and genetic investigation in family members].

Muir-Torre syndrome is a relatively rare cutaneous manifestation of hereditary nonpolypous colorectal cancer (HNPCC). This autosomal dominant syndrome is characterized by a combination of sebaceous gland and malignant visceral tumors. The common sites of internal malignancies are the gastrointestinal tract and urinary system. It appears in early adult life and its clinical course is relatively slow. In some families genetic diagnosis can identify asymptomatic carriers of the mutation. All first-degree relatives, especially mutation carriers, should be referred from the age of 20 years for routine follow-up and early treatment, as it has been proven to decrease morbidity and mortality. We present a 51-year-old man with Muir-Torre syndrome diagnosed by the presence of multiple adenomas of sebaceous glands, colonic adenoma and adenocarcinoma of the duodenum. The family history was typical for HNPCC. A mutation in the hMSH2 gene on chromosome 2p was found in the patient and in several asymptomatic family members. The aim of this report is to increase awareness of this syndrome and emphasize the importance of referring patients and their families for clinical and genetic counseling and diagnosis.

Bacteriuria following extracorporeal shock-wave lithotripsy in patients whose urine was sterile before the procedure.

During 10 months at our hospital, 413 patients underwent extracorporeal shock-wave lithotripsy (ESWL). The occurrence of complications was examined in the 126 (30.5%) of these patients who had sterile urine before the procedure and who had neither indwelling catheters nor stents. No patient received prophylactic antibiotics. After ESWL, nine patients (7%) developed bacteriuria, which was usually transient and required no therapy. Seven of the nine cases developed within 2 weeks of ESWL. In no case did other complications follow bacteriuria. Patients in whom bacteriuria was suspected because of fever all proved to have sterile urine. Our results indicate that patients whose urine is sterile before ESWL do not need antimicrobial prophylaxis.

Prevalence of the I1307K APC gene variant in Israeli Jews of differing ethnic origin and risk for colorectal cancer.

BACKGROUND & AIMS: Israeli Jews of European birth, i.e., Ashkenazim, have the highest colorectal cancer incidence of any Israeli ethnic group. The I1307K APC gene variant was found in 6.1% of American Jews, 28% of their familial colorectal cancer cases, but not in non-Jews. We assessed the I1307K prevalence in Israeli Jews of differing ethnic origin and risk for colorectal cancer. METHODS: DNA samples from 500 unrelated Jews of European or non-European origin, with or without a personal and/or family history of neoplasia, were examined for the I1307K variant by the allele-specific oligonucleotide (ASO) method. RESULTS: In persons at average risk for colorectal cancer, I1307K was found in 5.0% of 120 European and 1.6% of 188 non-European Jews (P = 0.08). It occurred in 15.4% of 52 Ashkenazi Israelis with familial cancer (P = 0.02) and was not detected in 51 non-European Jews at increased cancer risk. Colorectal neoplasia occurred personally or in the families of 13 of 20 Ashkenazi I1307K carriers, 8 of whom also had a personal or family history of noncolonic neoplasia. CONCLUSIONS: The I1307K APC variant may represent a susceptibility gene for colorectal, or other, cancers in Ashkenazi Jews, and partially explains the higher incidence of colorectal cancer in European Israelis.

Prospective assessment of microsatellite instability in gastrointestinal neoplasia in Ashkenazi and non-Ashkenazi Jews.

BACKGROUND: Microsatellite instability (MSI) is a useful marker of replication errors in neoplasia, resulting from mutations in the mismatch repair (MMR) genes. Nearly all hereditary non-polyposis colorectal cancer (HNPCC) and about 15% of sporadic colorectal cancers (CRC) exhibit high MSI (MSI-H). The use of the Amsterdam criteria for HNPCC diagnosis may fail to identify many HNPCC cases. Genetic screening of mutations in the MMR genes is laborious, time-consuming, expensive and limited by a low detection rate. Hence, MSI testing is a feasible and cost-effective method to select suspected HNPCC patients for genetic analysis. MSI has not been used routinely or prospectively in the assessment of newly diagnosed CRC. AIMS: To prospectively evaluate MSI status in a cohort of patients seen at the Gastrointestinal Oncology Unit of the Tel Aviv Medical Center. METHODS: Ninety-eight consecutive patients with colonic or gastric neoplasia were included. Samples from neoplastic and normal mucosa were obtained at the time of diagnostic endoscopy. MSI was determined based on five Bethesda markers using standard polymerase chain reaction procedures. RESULTS: The overall incidence of MSI was 20.4%. MSI-H was detected in 22.2% of CRC, 20% of colonic adenomas and 18.2% of gastric neoplasia. MSI-positive neoplasia tended to display multiple colonic sites, moderate-well differentiated tumors, and a higher rate of familial gastrointestinal neoplasia. CONCLUSIONS: MSI may be involved in the early stages of some colorectal tumorigenesis pathways since it may be detected in adenomas. MSI may serve as a cost-effective, reliable and important tool in the selection of HNPCC-suspected families for genetic testing. A small study population, referral bias or ethnic variation might explain the higher MSI rate. It is suggested that, similar to familial adenomatous polyposis, a state of attenuated HNPCC may exist. Hence, the clinical approach in positive patients, and their family members, should be conducted as for families with genetically proven HNPCC.