[Show abstract][Hide abstract] ABSTRACT: Objectives:
Hereditary biallelic mismatch repair deficiency (BMMRD) is caused by biallelic mutations in the mismatch repair (MMR) genes and manifests features of neurofibromatosis type 1, gastrointestinal (GI) polyposis, and GI, brain, and hematological cancers. This is the first study to characterize the GI phenotype in BMMRD using both retrospective and prospective surveillance data.
The International BMMRD Consortium was created to collect information on BMMRD families referred from around the world. All patients had germline biallelic MMR mutations or lack of MMR protein staining in normal and tumor tissue. GI screening data were obtained through medical records with annual updates.
Thirty-five individuals from seven countries were identified with BMMRD. GI data were available on 24 of 33 individuals (73%) of screening age, totaling 53 person-years. The youngest age of colonic adenomas was 7, and small bowel adenoma was 11. Eight patients had 19 colorectal adenocarcinomas (CRC; median age 16.7 years, range 8-25), and 11 of 18 (61%) CRC were distal to the splenic flexure. Eleven patients had 15 colorectal surgeries (median 14 years, range 9-25). Four patients had five small bowel adenocarcinomas (SBC; median 18 years, range 11-33). Two CRC and two SBC were detected during surveillance within 6-11 months and 9-16 months, respectively, of last consecutive endoscopy. No patient undergoing surveillance died of a GI malignancy. Familial clustering of GI cancer was observed.
The prevalence and penetrance of GI neoplasia in children with BMMRD is high, with rapid development of carcinoma. Colorectal and small bowel surveillance should commence at ages 3-5 and 8 years, respectively.Am J Gastroenterol advance online publication, 5 January 2016; doi:10.1038/ajg.2015.392.
Full-text · Article · Jan 2016 · The American Journal of Gastroenterology
[Show abstract][Hide abstract] ABSTRACT: A 46-year-old female presents with a pelvic mass and is diagnosed as having a high-grade endometrial stromal sarcoma. During surgery, she is noted to have areas of intussusception of the small bowel secondary to large hamartomatous polyps. The patient had a previous history of small bowel obstruction secondary to what had been thought to be hyperplastic polyps but represented hamartomatous polyps on further review. Additional examination revealed the presence of subtle hyperpigmented macules on the fingers leading to a diagnosis of Peutz-Jeghers Syndrome (PJS). The diagnosis was confirmed by the presence of a germ-line STK11 mutation. Immunohistochemistry analysis of the tumor showed decreased expression of STK-11 as compared to one of the patient's hamartomatous polyps. Next generation sequencing of the tumor specimen failed to demonstrate a "second hit" somatic mutation in STK-11. This case represents the first case of endometrial stromal sarcoma associated with PJS and illustrates the importance of increased awareness of this condition among oncologists. PJS is associated with dysregulation of the mTOR pathway; treatment with an mTOR inhibitor was not effective in this case.
Full-text · Article · Dec 2015 · Hereditary Cancer in Clinical Practice
[Show abstract][Hide abstract] ABSTRACT: Objective To understand motivations, educational needs, and concerns of individuals contemplating whole-exome sequencing (WES) and determine what amount of genetic information might be obtained by sequencing a generally healthy cohort so as to more effectively counsel future patients. Patients and Methods From 2012 to 2014, 40 medically educated, generally healthy scientists at Mayo Clinic were invited to have WES conducted on a research basis; 26 agreed to be in a drawing from which 10 participants were selected. The study involved pre- and posttest genetic counseling and completion of 4 surveys related to the experience and outcomes. Whole-exome sequencing was conducted on DNA from blood from each person. Results Most variants (76,305 per person; range, 74,505-77,387) were known benign allelic variants, variants in genes of unknown function, or variants of uncertain significance in genes of known function. The results of suspected pathogenic/pathogenic variants in Mendelian disorders and pharmacogenomic variants were disclosed. The mean number of suspected pathogenic/pathogenic variants was 2.2 per person (range, 1-4). Four pharmacogenomic genes were included for reporting; variants were found in 9 of 10 participants. Conclusion This study provides data that may be useful in establishing reality-based patient expectations, outlines specific points to cover during counseling, and increases confidence in the feasibility of providing adequate preparation and counseling for WES in generally healthy individuals.
Full-text · Article · Oct 2015 · Mayo Clinic Proceedings
[Show abstract][Hide abstract] ABSTRACT: Germ-line mutations in MLH1, MSH2, MSH6, and PMS2 have been shown to cause Lynch syndrome. The penetrance of the cancer and tumor spectrum has been repeatedly studied, and multiple professional societies have proposed clinical management guidelines for affected individuals. Several studies have demonstrated a reduced penetrance for monoallelic carriers of PMS2 mutations compared with the other mismatch repair (MMR) genes, but clinical management guidelines have largely proposed the same screening recommendations for all MMR gene carriers. The authors considered whether enough evidence existed to propose new screening guidelines specific to PMS2 mutation carriers with regard to age at onset and frequency of colonic screening. Published reports of PMS2 germ-line mutations were combined with unpublished cases from the authors' research registries and clinical practices, and a discussion of potential modification of cancer screening guidelines was pursued. A total of 234 monoallelic PMS2 mutation carriers from 170 families were included. Approximately 8% of those with colorectal cancer (CRC) were diagnosed before age 30, and each of these tumors presented on the left side of the colon. As it is currently unknown what causes the early onset of CRC in some families with monoallelic PMS2 germline mutations, the authors recommend against reducing cancer surveillance guidelines in families found having monoallelic PMS2 mutations in spite of the reduced penetrance.Genet Med advance online publication 09 April 2015Genetics in Medicine (2015); doi:10.1038/gim.2015.27.
No preview · Article · Apr 2015 · Genetics in medicine: official journal of the American College of Medical Genetics
[Show abstract][Hide abstract] ABSTRACT: Discriminating neoplastic from non-neoplastic polyps can significantly reduce the cost of colonoscopy. The American Society for Gastrointestinal Endoscopy (ASGE) recently set threshold levels for optical diagnostic accuracy to be acceptable for clinical use.
No preview · Article · Jun 2014 · Gastrointestinal Endoscopy
[Show abstract][Hide abstract] ABSTRACT: Purpose:
The Muir-Torre syndrome variant of Lynch syndrome is characterized by the presence of sebaceous neoplasms (adenoma, epithelioma/sebaceoma, carcinoma) and Lynch syndrome-associated cancers (colon, endometrial, and others). Several clinical scoring systems have been developed to identify patients with colon cancer at high risk of Lynch syndrome. However, no such system has been described for patients presenting with sebaceous neoplasms.
Based on logistic regression analysis, a scoring system was developed for patients with sebaceous neoplasm to identify those with the highest likelihood of having Muir-Torre syndrome. The final version of the scoring system included variables such as age at presentation of initial sebaceous neoplasm, total number of sebaceous neoplasms, personal history of a Lynch-related cancer, and family history of Lynch-related cancers.
Patients with a score of 3 or more were more likely to have Muir-Torre syndrome (28 of 29 patients), those with a score of 2 had intermediate likelihood (12 of 20 patients), and no patient with a score of 0 or 1 was diagnosed with Muir-Torre syndrome.
The Mayo Muir-Torre syndrome risk scoring system appears to identify whether patients who present with sebaceous neoplasms are in need of further Lynch syndrome evaluation using easily ascertained clinical information. Abnormal mismatch repair gene immunohistochemistry of a sebaceous neoplasm is a poor predictor in regard to diagnosing Lynch syndrome.
No preview · Article · Mar 2014 · Genetics in medicine: official journal of the American College of Medical Genetics
[Show abstract][Hide abstract] ABSTRACT: Telomeres are nucleoprotein structures that cap the end of chromosomes and shorten with sequential cell divisions in normal aging. Short telomeres are also implicated in the incidence of many cancers, but the evidence is not conclusive for colorectal cancer (CRC). Therefore, the aim of this study was to assess the association of CRC and telomere length.
In this case-control study, we measured relative telomere length from peripheral blood leukocytes (PBLs) DNA with quantitative PCR in 598 CRC patients and 2,212 healthy controls.
Multivariate analysis indicated that telomere length was associated with risk for CRC, and this association varied in an age-related manner; younger individuals (≤50 years of age) with longer telomeres (80-99 percentiles) had a 2-6 times higher risk of CRC, while older individuals (>50 years of age) with shortened telomeres (1-10 percentiles) had 2-12 times the risk for CRC. The risk for CRC varies with extremes in telomere length in an age-associated manner.
Younger individuals with longer telomeres or older individuals with shorter telomeres are at higher risk for CRC. These findings indicate that the association of PBL telomere length varies according to the age of cancer onset and that CRC is likely associated with at minimum two different mechanisms of telomere dynamics.
Full-text · Article · Mar 2014 · Clinical and Translational Gastroenterology
[Show abstract][Hide abstract] ABSTRACT: Patients with familial adenomatous polyposis (FAP) are known to have an increased risk for gastric adenomas. The clinical features of gastric adenomas in FAP have not been well characterized, and there is a lack of standardized approaches to the management of these lesions.
To study the endoscopic appearance, risk factors, clinical course, and response to therapy of gastric adenomas in patients with FAP.
We retrospectively reviewed the records of 97 patients with FAP who underwent esophagogastroduodenoscopy (EGD) at Mayo Clinic (Florida, Rochester and Arizona) between 2004 and 2013.
Nine patients (9%) had biopsy-proven gastric adenomas. Adenomas were located in the antrum (five patients), in the body and fundus in the setting of background fundic gland polyps (FGP) (three patients), and in the body not associated with FGP (one patient). Adenoma size was 3-40 mm and the number of adenomas per patient ranged from one to 20. Adenomas in the antrum were flat and subtle, whereas those in the gastric body or fundus were polypoid and difficult to differentiate from the cystic FGPs seen in patients with FAP. The performing endoscopists reported difficulty with identifying adenomas, and six patients had at least one EGD within the previous three years where gastric adenomas were not reported. Adenomas were classified as tubular in eight patients and tubulovillous in one patient. High grade dysplasia was noted in one patient. After a median follow-up of 63 months (interquartile range: 20-149 months), no patient in our entire cohort (with or without gastric adenomas) developed gastric cancer. The patients in whom gastric adenoma developed, compared to those without gastric adenoma, were more likely to be younger [36 +/- 12 vs. 48 +/- 15 years, p = 0.02], have concomitant chronic gastritis [22% vs. 0%, p = 0.008], and have desmoid tumors [5(56%) vs. 19(22%), p 0.04]002E CONCLUSIONS: Gastric adenomas are not uncommon in patients with FAP and are often difficult to identify endoscopically. Endoscopists should have a high degree of suspicion for gastric adenomas in these patients and a low threshold to biopsy. Given the benign clinical course, recommended initial management is conservative with endoscopic therapy and periodic surveillance.
Preview · Article · Feb 2014 · Hereditary Cancer in Clinical Practice
[Show abstract][Hide abstract] ABSTRACT: Heterozygous loss-of-function SMAD4 mutations are associated with juvenile polyposis syndrome and hereditary hemorrhagic telangiectasia. Some carriers exhibit symptoms of both conditions, leading to juvenile polyposis-hereditary hemorrhagic telangiectasia syndrome. Three families have been reported with connective tissue abnormalities. To better understand the spectrum and extent of clinical findings in SMAD4 carriers, medical records of 34 patients (20 families) from five clinical practices were reviewed. Twenty-one percent of the patients (7/34) had features suggesting a connective tissue defect: enlarged aortic root (n = 3), aortic and mitral insufficiency (n = 2), aortic dissection (n = 1), retinal detachment (n = 1), brain aneurysms (n = 1), and lax skin and joints (n = 1). Juvenile polyposis-specific findings were almost uniformly present but variable. Ninety-seven percent of the patients had colon polyps that were generally pan-colonic and of variable histology and number. Forty-eight percent of the patients (15/31) had extensive gastric polyposis. Hereditary hemorrhagic telangiectasia features, including epistaxis (19/31, 61%), mucocutaneous telangiectases (15/31, 48%), liver arteriovenous malformation (6/16, 38%), brain arteriovenous malformation (1/26, 4%), pulmonary arteriovenous malformation (9/17, 53%), and intrapulmonary shunting (14/23, 61%), were documented in 76% of the patients. SMAD4 carriers should be managed for juvenile polyposis and hereditary hemorrhagic telangiectasia because symptoms of both conditions are likely yet unpredictable. Connective tissue abnormalities are an emerging component of juvenile polyposis-hereditary hemorrhagic telangiectasia syndrome, and larger studies are needed to understand these manifestations.Genet Med advance online publication 13 February 2014Genetics in Medicine (2014); doi:10.1038/gim.2014.5.
Preview · Article · Feb 2014 · Genetics in medicine: official journal of the American College of Medical Genetics
[Show abstract][Hide abstract] ABSTRACT: Colorectal cancer (CRC) tumor DNA is characterized by chromosomal damage termed chromosomal instability (CIN) and excessively shortened telomeres. Up to 80% of CRC is microsatellite stable (MSS) and is historically considered to be chromosomally unstable (CIN+). However, tumor phenotyping depicts some MSS CRC with little or no genetic changes, thus being chromosomally stable (CIN-). MSS CIN- tumors have not been assessed for telomere attrition.
MSS rectal cancers from patients ≤50 years old with Stage II (B2 or higher) or Stage III disease were assessed for CIN, telomere length and telomere maintenance mechanism (telomerase activation [TA]; alternative lengthening of telomeres [ALT]). Relative telomere length was measured by qPCR in somatic epithelial and cancer DNA. TA was measured with the TRAPeze assay, and tumors were evaluated for the presence of C-circles indicative of ALT. p53 mutation status was assessed in all available samples. DNA copy number changes were evaluated with Spectral Genomics aCGH.
Tumors were classified as chromosomally stable (CIN-) and chromosomally instable (CIN+) by degree of DNA copy number changes. CIN- tumors (35%; n=6) had fewer copy number changes (<17% of their clones with DNA copy number changes) than CIN+ tumors (65%; n=13) which had high levels of copy number changes in 20% to 49% of clones. Telomere lengths were longer in CIN- compared to CIN+ tumors (p=0.0066) and in those in which telomerase was not activated (p=0.004). Tumors exhibiting activation of telomerase had shorter tumor telomeres (p=0.0040); and tended to be CIN+ (p=0.0949).
MSS rectal cancer appears to represent a heterogeneous group of tumors that may be categorized both on the basis of CIN status and telomere maintenance mechanism. MSS CIN- rectal cancers appear to have longer telomeres than those of MSS CIN+ rectal cancers and to utilize ALT rather than activation of telomerase.
[Show abstract][Hide abstract] ABSTRACT: Cultural, religious, and financial barriers may hinder uptake of CRC screening in Arab communities. We aim to understand attitudes and barriers that contribute to the low rate of CRC screening among Palestinians in the West Bank.
This was a national, cross-sectional study of Palestinian adults over 50 years of age. A self-administered questionnaire was developed and validated. Data was randomly collected in all major districts of the West Bank. The primary outcome was the willingness to undergo CRC screening. Multivariable logistic regression models were used to assess the strength of association between the primary outcome and its predictors while controlling for possible confounders.
Of 1601 people approached for interview, 1352 agreed to participate (response rate 84%). Rate of CRC screening was very low (14%, n=193). Willingness to undergo CRC screening was 79% for Fecal Occult Blood Testing and 67% for colonoscopy. Most people, 81% (1098), were willing to undergo CRC screening if recommended by a physician. Only 14% (n=194) said they were informed about CRC screening by a physician. Urban residents were more likely to be screened for CRC compared to non-urban residents (OR 0.73 [0.56-0.93], p=0.011). Multivariable analysis showed that education below secondary school, lack of familiarity with CRC screening, distrust of Western medicine, religious objection, and finding the test to be embarrassing were all associated with decreased odds of accepting CRC screening.
Understanding cultural and religious barriers to CRC screening among Arabs can help understand barriers to CRC screening in Arab populations in the Middle East and in Western countries.
No preview · Article · Sep 2013 · Clinical gastroenterology and hepatology: the official clinical practice journal of the American Gastroenterological Association
[Show abstract][Hide abstract] ABSTRACT: Background: Both shorter and longer telomeres in peripheral blood leukocyte (PBL) DNA have been associated with cancer risk. However, associations remain inconsistent across studies of the same cancer type. This study compares DNA preparation methods to determine telomere length from colorectal cancer patients. Methods: We examined PBL relative telomere length (RTL) measured by quantitative PCR (qPCR) in 1,033 colorectal cancer patients and 2,952 healthy controls. DNA was extracted with Phenol/Chloroform, PureGene or QIAamp. Results: We observed differences in RTL depending on DNA extraction method (p<0.001). Phenol/Chloroform extracted DNA had a mean RTL (T/S ratio) of 0.78 (range 0.01-6.54) ) compared to PureGene extracted DNA (mean RTL of 0.75; range 0.00-12.33). DNA extracted by QIAamp yielded a mean RTL of 0.38 (range 0.02-3.69). We subsequently compared RTL measured by qPCR from an independent set of 20 colorectal cancer cases and 24 normal controls in PBL DNA extracted by each of the three extraction methods. The range of RTL measured by qPCR from QIAamp-extracted DNA (0.17-0.58-) was smaller than from either PureGene or Phenol/Chloroform (ranges: 0.04-2.67 and 0.32-2.81, respectively). Conclusions: RTL measured by qPCR from QIAamp-extracted DNA was smaller than from either PureGene or Phenol/Chloroform (p<0.001). Impact: Differences in DNA extraction method may contribute to the discrepancies between studies seeking to find an association between the risk of cancer or other diseases and RTL.
No preview · Article · Sep 2013 · Cancer Epidemiology Biomarkers & Prevention
[Show abstract][Hide abstract] ABSTRACT: Screening for the Muir-Torre variant of Lynch Syndrome (LS) using Mismatch Repair (MMR) gene immunohistochemistry (IHC) on sebaceous neoplasms (SNs) is technically feasible. To date, research into the clinical utility of MMR IHC for this indication is limited. We conducted a retrospective chart review of 90 patients with MMR IHC completed on at least one SN from January 2005 to May 2010. SNs included were adenomas, epitheliomas, carcinomas and basal and squamous cell carcinomas with sebaceous differentiation. Of the 90 patients, 13 (14 %) had genetically confirmed or fulfilled clinical criteria for a diagnosis of MTS and 51 patients (57 %) presented with an abnormal MMR IHC result (loss of one or more MMR proteins) on at least one SN. Abnormal IHC had a sensitivity of 85 %, specificity of 48 %, positive predictive value (PPV) of 22 % and negative predictive value (NPV) of 95 % when evaluating for MTS. When personal or family history of colorectal cancer (≥2 family members with a history of colorectal cancer) was taken into consideration, ignoring IHC results, sensitivity was 92 %, specificity was 99 %, PPV was 92 % and NPV was 99 %. MMR IHC on SNs when used to screen for MTS has poor diagnostic utility. We recommend that MMR IHC not be performed routinely on SNs when the patient does not have either personal or family history of colorectal cancer.
No preview · Article · Dec 2012 · Journal of Genetic Counseling
[Show abstract][Hide abstract] ABSTRACT: Background:
Colorectal cancer (CRC) can be prevented by the early detection and removal of advanced adenomas (AAs) by colonoscopy. Our aim was to evaluate peripheral blood leukocyte (PBL) telomere length as a potential biomarker for the presence of AAs.
PBL telomere length was measured in patients with AAs (n=35), in a control group of similarly aged patients who had a normal colonoscopy (n=145) and in a separate population group with no history of cancer, again similarly aged (n=495). Telomere measurements were performed using a quantitative PCR assay and reported as ratios of telomere and single copy gene measurements.
Telomere lengths tended to be lower in patients with AAs than in patients in the normal colonoscopy group (p<0.001) as well as those in the population group (p=0.011). A telomere/single copy gene ratio of 0.5 was found to have an estimated 94% sensitivity and a 56% specificity for AAs; a combination of sensitivity and specificity for which a value of >0.5 would reduce the odds of a patient having AAs by a factor of 0.11 (the negative likelihood ratio). Thirty three percent of individuals in the population group tested above this cutoff and could be considered at low risk for AAs.
PBL telomeres are shortened in patients with colorectal neoplasia, suggesting that PBL telomere length could be a promising non-invasive blood biomarker to pre-screen for risk of AAs prior to colonoscopy.
No preview · Article · Jul 2012 · The International journal of biological markers
[Show abstract][Hide abstract] ABSTRACT: The surgical management of pancreatic endocrine tumors in patients with multiple endocrine neoplasia type 1 (MEN-1) is controversial and complicated by the fact that these tumors are frequently multifocal. The degree of tumor resection is determined by weighing the risk of malignancy or tumor recurrence against the risks of endocrine/exocrine insufficiency with complete gland removal.
A retrospective review was performed identifying 4 patients with MEN-1 and pancreatic endocrine tumors treated with pancreatic resection over a 2-year period at our institution.
Mean age at operation was 35 years. Surgical approach was determined by size of tumor(s) and presence of multifocality. MRI and EUS were performed in all patients. While EUS identified a greater number of tumors when compared to MRI (median 5 versus 1), both studies grossly underestimated the total number of tumors found on final pathology. Three patients underwent laparoscopic total pancreatectomy for multifocal disease with diffuse pancreatic involvement, finding a median of 12 tumors. One patient underwent laparoscopic subtotal pancreatectomy for a presumed single pancreatic tail mass, but was found to have multifocal disease on final pathology consisting of 7 tumors. The average number of tumors found on final pathology was 13.5 with an average size of 2.6 cm. The median number of lymph nodes analyzed was 14. Diffuse, multifocal disease was present in all 4 patients. No major postoperative complications were observed.
In patients with MEN-1 and pancreatic endocrine tumors, preoperative workup underestimates extent of disease and total pancreatectomy should be considered for complete tumor removal.
No preview · Article · Jul 2012 · JOP: Journal of the pancreas
[Show abstract][Hide abstract] ABSTRACT: Ampullary and extensive periampullary lesions can be difficult to treat and often require pancreaticoduodenectomy (PD) for complete removal, even if benign. However, PD may be overtreatment for noninvasive lesions, and pancreas-sparing total duodenectomy (PSTD) is an emerging valid surgical option for selected cases.
We reviewed patients undergoing PSTD at our institution over 16 months and a comparison group who had undergone PD for benign duodenal disease over the past 15 years. We also reviewed cases in the English-language literature and performed a meta-analysis of those patients who had undergone PSTD.
PSTD had been performed in four patients, who had an average hospital length of stay (LOS) of 13 days; two of them experienced complications. None required conversion to PD, experienced a postoperative fistula or endocrine or exocrine insufficiency, or required intensive care. Two of the PSTDs were performed laparoscopically. Open PD for benign duodenal disease was performed in 22 patients, with overall morbidity and pancreas fistula rates of 82 and 27 %, respectively. The meta-analysis found 128 unique cases of PSTD with morbidity and mortality rates of 46.4 and 2.3 %, respectively. Pancreaticobiliary leak was seen in 20 %, with an average LOS of 17 days.
Although PSTD can be used to avoid PD and can be performed laparoscopically, it is technically challenging and still associated with morbidity.
No preview · Article · Jun 2012 · World Journal of Surgery