Biomedical subjects

Gloria M Petersen

Publications and source records attributed to Gloria M Petersen.

At least 19 recordsLinked to original sources

PubMed2007

Identification of a novel tumor suppressor gene p34 on human chromosome 6q25.1.

In this study, we observed loss of heterozygosity (LOH) in human chromosomal fragment 6q25.1 in sporadic lung cancer patients. LOH was observed in 65% of the 26 lung tumors examined and was narrowed down to a 2.2-Mb region. Single-nucleotide polymorphism (SNP) analysis of genes located within this region identified a candidate gene, termed p34. This gene, also designated as ZC3H12D, C6orf95, FLJ46041, or dJ281H8.1, carries an A/G nonsynonymous SNP at codon 106, which alters the amino acid from lysine to arginine. Nearly 73% of heterozygous lung cancer tissues with LOH and the A/G SNP also exhibited loss of the A allele. In vitro clonogenic and in vivo nude mouse studies showed that overexpression of the A allele exerts tumor suppressor function compared with the G allele. p34 is located within a recently mapped human lung cancer susceptibility locus, and association of the p34 A/G SNP was tested among these families. No significant association between the less frequent G allele and lung cancer susceptibility was found. Our results suggest that p34 may be a novel tumor suppressor gene involved in sporadic lung cancer but it seems not to be the candidate familial lung cancer susceptibility gene linked to chromosomal region 6q23-25.

Alleles↗

PubMed2006

Recommendations for the care of individuals with an inherited predisposition to Lynch syndrome: a systematic review.

CONTEXT: About 2% of all colorectal cancer occurs in the context of the autosomal dominantly inherited Lynch syndrome, which is due to mutations in mismatch repair genes. Potential risk-reducing interventions are recommended for individuals known to have these mutations. OBJECTIVES: To review cancer risks and data on screening efficacy in the context of Lynch syndrome (hereditary nonpolyposis colorectal cancer) and to provide recommendations for clinical management for affected families, based on available evidence and expert opinion. DATA SOURCES AND STUDY SELECTION: A systematic literature search using PubMed and the Cochrane Database of Systematic Reviews, reference list review of retrieved articles, manual searches of relevant articles, and direct communication with other researchers in the field. Search terms included hereditary non-polyposis colon cancer, Lynch syndrome, microsatellite instability, mismatch repair genes, and terms related to the biology of Lynch syndrome. Only peer-reviewed, full-text, English-language articles concerning human subjects published between January 1, 1996, and February 2006 were included. The US Preventive Services Task Force's 2-tier system was adapted to describe the quality of evidence and to assign strength to the recommendations for each guideline. EVIDENCE SYNTHESIS: The evidence supports colonoscopic surveillance for individuals with Lynch syndrome, although the optimal age at initiation and frequency of examinations is unresolved. Colonoscopy is recommended every 1 to 2 years starting at ages 20 to 25 years (age 30 years for those with MSH6 mutations), or 10 years younger than the youngest age of the person diagnosed in the family. While fully acknowledging absence of demonstrated efficacy, the following are also recommended annually: endometrial sampling and transvaginal ultrasound of the uterus and ovaries (ages 30-35 years); urinalysis with cytology (ages 25-35 years); history, examination, review of systems, education and genetic counseling regarding Lynch syndrome (age 21 years). Regular colonoscopy was favored for at-risk persons without colorectal neoplasia. For individuals who will undergo surgical resection of a colon cancer, subtotal colectomy is favored. Evidence supports the efficacy of prophylactic hysterectomy and oophorectomy. CONCLUSIONS: The past 10 years have seen major advances in the understanding of Lynch syndrome. Current recommendations regarding cancer screening and prevention require careful consultation between clinicians, clinical cancer genetic services, and well-informed patients.

Adult↗

PubMed2006

Familial aggregation of fainting in a case-control study of neurally mediated hypotension patients who present with unexplained chronic fatigue.

AIMS: We hypothesized that family history of fainting is a risk factor for adult-onset neurally mediated hypotension (NMH) in patients who present with chronic fatigue rather than fainting. METHODS AND RESULTS: A nested case-control study of Gulf War veterans gathered fainting histories directly from 197 first-degree relatives of 16 fatigued NMH cases, 26 fatigued controls, and 17 healthy controls. NMH status was determined by tilt testing. Female relatives of fatigued controls reported more fainting than female relatives of cases (P<0.01); there were no significant differences in the frequency of fainting in male relatives by case or control status, or in either gender by age at first faint or by familial relationship to the proband. The odds of NMH patients giving any family history of fainting were 0.56 (95% CI 0.15, 2.07). Recurrence risks calculated using lifetime prevalences of fainting in male military personnel of similar age to our participants were low (1.5-1.7) and did not differ by case or control status. CONCLUSION: Family history of fainting is not a risk factor for adult-onset NMH in fatigued veterans. Our findings may differ from other studies of familial aggregation in NMH because of study methods or because NMH-fatiguers may differ from NMH-fainters.

Adult↗

PubMed2006

Association of family history of specific cancers with a younger age of onset of pancreatic adenocarcinoma.

BACKGROUND & AIMS: Pancreatic adenocarcinoma has been associated with several familial cancer syndromes that also predispose to other malignancies. Younger ages of onset of pancreatic cancer (PC) have been reported in families with these syndromes. METHODS: Six hundred twenty-four consecutive patients (probands) from the Mayo Clinic Pancreatic Cancer Patient Registry who completed questionnaires were analyzed for family history of cancer and cigarette smoking. The ages at diagnosis of those probands who reported a family history (first- or second-degree relative) of PC, breast, ovarian, colorectal cancer, or melanoma were compared with those probands who did not. Multivariable regression analyses were performed with age at diagnosis as the primary outcome variable. RESULTS: As expected, smokers had a younger median age of onset of PC than nonsmokers in dose-dependent fashion (P = .0003). After controlling for tobacco exposure and gender, those probands with a family history of breast (-3.23 years, P = .001), ovarian (-5.63 years, P = .005), colorectal (-3.19 years, P = .002) cancers, and melanoma (-5.75 years, P = .017) had a younger age of onset of PC than those who did not. Those with a family history of PC (-.61 years, P = .65) exhibited no difference. Probands reporting other cancers in relatives showed no difference (+.78 years, P = .49) in age of onset of PC. CONCLUSION: A family history of cancers (breast, ovarian, colorectal, melanoma) associated with specific cancer syndromes that are known to contribute also to PC risk is associated with a younger onset of PC. A family history of PC does not appear to affect age of onset of PC.

Adenocarcinoma↗

PubMed2006

Screening for early pancreatic neoplasia in high-risk individuals: a prospective controlled study.

BACKGROUND & AIMS: Individuals with a strong family history of pancreatic cancer and persons with Peutz-Jeghers syndrome (PJS) have an increased risk for pancreatic cancer. This study screened for early pancreatic neoplasia and compared the pancreatic abnormalities in high-risk individuals and control subjects. METHODS: High-risk individuals with PJS or a strong family history of pancreatic cancer were prospectively evaluated with baseline and 12-month computed tomography (CT) scan and endoscopic ultrasonography (EUS). If EUS was abnormal, EUS-fine-needle aspiration and endoscopic retrograde cholangiopancreatography (ERCP) were performed. Surgery was offered to patients with potentially neoplastic lesions. Radiologic findings and pathologic diagnoses were compared. Patients undergoing EUS and/or ERCP for benign non-pancreatic indications were concurrently enrolled as control subjects. RESULTS: Seventy-eight high-risk patients (72 from familial pancreatic cancer kindreds, 6 PJS) and 149 control patients were studied. To date, 8 patients with pancreatic neoplasia have been confirmed by surgery or fine-needle aspiration (10% yield of screening); 6 patients had 8 benign intraductal papillary mucinous neoplasms (IPMNs), 1 had an IPMN that progressed to invasive ductal adenocarcinoma, and 1 had pancreatic intraepithelial neoplasia. EUS and CT also diagnosed 3 patients with 5 extrapancreatic neoplasms. At EUS and ERCP abnormalities suggestive of chronic pancreatitis were more common in high-risk patients than in control subjects. CONCLUSIONS: Screening EUS and CT diagnosed significant asymptomatic pancreatic and extrapancreatic neoplasms in high-risk individuals. IPMN should be considered a part of the phenotype of familial pancreatic cancer. Abnormalities suggestive of chronic pancreatitis are identified more commonly at EUS and ERCP in high-risk individuals.

Adult↗

PubMed2006

Opportunities and barriers in the age of team science: strategies for success.

OBJECTIVE: To provide the voice of experience to investigators contemplating engagement in the realm of "team science". METHODS: Leaders were brought together from academia, government, and industry to share perspectives and insights based on real-life experiences. A panel discussion was held at the 2005 annual meeting of the American Association of Cancer Research. This article summarizes that forum. RESULTS: The panel focused on eight specific topics that were determined in advance to be the most important: the main justification for team science, funding team science, pre-arranged versus assigned partnerships, the role of novel technology with industrial partners, recognition for efforts and contribution in team science, budgets, keys to success when bridging disciplines and cultures, and balancing goals between academia and business. Although there were some differences of opinion, there were also a number of areas of agreement. Many practical suggestions were provided on how to succeed in the age of team science. PRINCIPAL CONCLUSION: The nature of scientific discovery in cancer research is increasingly requiring team science. Understanding the perspectives of academia, government, and business in this new world order is essential to successful navigation and, ultimately, major accomplishment in the effort to defeat the disease.

Biotechnology↗

PubMed2006

Case-control genetic association studies in gastrointestinal disease: review and recommendations.

As our knowledge of genetic variation grows, our ability to use this information to unravel the mysteries of human disease expands. Identification of genes and inexpensive methods to sequence them has resulted in a rising interest in evaluating specific variants and whether they may result in clinical manifestations or symptoms. Genetic variants include restriction fragment length polymorphisms, variable number tandem repeats, DNA microsatellites, and single nucleotide polymorphisms. Using these variants, genetic association studies, also referred to as candidate gene association or genotype-disease association studies are being performed by clinical and basic researchers alike. They are relatively easy to perform, but as a result of their deceivingly simple design, can be conducted or interpreted poorly. A positive association between a genotype and a GI disease of interest may be because the genotype causes (or increases susceptibility to) the disease, but may also be the result of the genotype being in linkage disequilibrium with the actual disease susceptibility gene, or be a false positive due to chance or bias in study design. An excellent understanding of the genetic and methodological issues surrounding these studies is therefore essential. We provide an overview of terminology and provide insight into the complexities underlying these studies. Recommendations for reporting the results of a genetic association study are provided to assist with study planning and manuscript preparation.

Case-Control Studies↗

PubMed2006

Pancreatic cancer genetic epidemiology consortium.

We have organized the Pancreatic Cancer Genetic Epidemiology (PACGENE) Consortium to identify susceptibility genes in familial pancreatic cancer (FPC). The Consortium comprises seven data collection centers, a statistical genetics core, and a pathology/archival genotyping core. We recruit kindreds containing two or more affected blood relatives ascertained through incident pancreatic adenocarcinoma cases, physician referrals, and/or through Internet recruitment. Accrual to a database containing core clinical, demographic, lifestyle, and family history information from questionnaires is ongoing, along with biospecimen collection. To date, 13,147 patients have been screened for family history, of whom 476 (50% male) probands and 1,912 of their adult (99% unaffected) relatives have been enrolled. Of these, 379 kindreds meet criteria for FPC, having at least two first-degree relatives with pancreatic cancer. Cumulative incidence curves using available age of diagnosis (onset) among and affected relatives were compared with those for incident pancreatic cancer cases reported to 13 U.S. Surveillance Epidemiology and End Results (SEER) sites from 1973 to 2000 (N = 72,700). The mean age +/- SD at diagnosis among 466 PACGENE probands and 670 affected relatives was 64.1 +/- 11.8 and was 65.4 +/- 11.6 for the subset of 369 FPC probands and 429 relatives. Both samples were significantly younger than the mean age at diagnosis in the SEER population (70.0 +/- 12.1 years; differences in curves versus SEER, P < 0.001). Age at diagnosis (excluding probands) in FPC kindreds does not decrease with increasing number of affected individuals. In our sample, younger age at diagnosis was observed whether we grouped probands by recruitment sites that predominantly recruited through high-risk referrals, or through screening all pancreatic cancer patients for family history. Linkage studies are ongoing. The PACGENE Consortium will be a valuable family-based resource that will greatly enhance genetic epidemiology research in pancreatic cancer.

Age of Onset↗

PubMed2005

Risk of malignancy in first-degree relatives of patients with pancreatic carcinoma.

BACKGROUND: Approximately 5-10% of pancreatic carcinoma (PC) patients report a family history of the disease. In some families, mutations of tumor suppressor genes have been elucidated, but for most the causative gene remains unidentified. Counseling the families of PC patients regarding their risk of cancer remains problematic because little information is available. METHODS: The authors analyzed family history questionnaires completed by 426 unselected, sequential Mayo Clinic patients with PC. The prevalence of malignancy reported among 3355 of their first-degree relatives was compared with the Surveillance, Epidemiology, and End Results Project (SEER) 9 (2000) registry. Age-adjusted and gender-adjusted standardized incidence ratios (SIRs) were generated. RESULTS: Greater than 130,000 person-years at risk for cancer among the first-degree relatives were analyzed. The risk of PC was found to be increased among the first-degree relatives of patients with PC (SIR of 1.88; 95% confidence interval [95% CI], 1.27-2.68), as was the risk of liver carcinoma (SIR of 2.70; 95% CI, 1.51-4.46). Lymphoma (SIR of 0.28; 95% CI, 0.12-0.55), bladder carcinoma (SIR of 0.55; 95% CI, 0.31-0.89), breast carcinoma (SIR of 0.73; 95% CI, 0.57-0.92), lung carcinoma (SIR of 0.62; 95% CI, 0.47-0.80), and prostate carcinoma (SIR of 0.71; 95% CI, 0.54-0.92) were found to be underrepresented. When the proband was age < 60 years, the risk of PC to first-degree relatives was found to be increased further (SIR of 2.86; 95% CI, 1.15-5.89). In this subgroup, no other malignancies were found to be significantly increased, although the risks of melanoma (SIR of 1.73; 95% CI, 0.70-3.57), ovarian carcinoma (SIR of 2.20; 95% CI, 0.72-5.12), and colon carcinoma (SIR of 1.37; 95% CI, 0.80-2.19) were suggestive. CONCLUSIONS: There was a nearly twofold increased risk of PC in the first-degree relatives of PC probands. This risk was found to increase nearly threefold when patients were diagnosed before age 60 years. At the current time, in the absence of a pedigree suggestive of known familial cancer syndromes, the current study results do not support targeted screening for other malignancies in the first-degree relatives of patients with sporadic PC.

Adult↗

PubMed2005

Lower cancer incidence in Amsterdam-I criteria families without mismatch repair deficiency: familial colorectal cancer type X.

CONTEXT: Approximately 60% of families that meet the Amsterdam-I criteria (AC-I) for hereditary nonpolyposis colorectal cancer (HNPCC) have a hereditary abnormality in a DNA mismatch repair (MMR) gene. Cancer incidence in AC-I families with MMR gene mutations is reported to be very high, but cancer incidence for individuals in AC-I families with no evidence of an MMR defect is unknown. OBJECTIVE: To determine if cancer risks in AC-I families with no apparent deficiency in DNA MMR are different from cancer risks in AC-I families with DNA MMR abnormalities. DESIGN, SETTING, AND PARTICIPANTS: Identification (1997-2001) of 161 AC-I pedigrees from multiple population- and clinic-based sources in North America and Germany, with families grouped into those with (group A) or without (group B) MMR deficiency by tumor testing. A total of 3422 relatives were included in the analyses. MAIN OUTCOME MEASURES: Cancer incidence in groups A and B (excluding the 3 affected members used to define each pedigree as AC-I) and computed age- and sex-adjusted standardized incidence ratios (SIRs) using Surveillance, Epidemiology, and End Results data. RESULTS: Group A families from both population- and clinic-based series showed increased incidence of the HNPCC-related cancers. Group B families showed increased incidence only for colorectal cancer (SIR, 2.3; 95% confidence interval, 1.7-3.0) and to a lesser extent than group A (SIR, 6.1; 95% confidence interval, 5.2-7.2) (P<.001). CONCLUSIONS: Families who fulfill AC-I criteria but who have no evidence of a DNA MMR defect do not share the same cancer incidence as families with HNPCC-Lynch syndrome (ie, hereditary MMR deficiency). Relatives in such families have a lower incidence of colorectal cancer than those in families with HNPCC-Lynch syndrome, and incidence may not be increased for other cancers. These families should not be described or counseled as having HNPCC-Lynch syndrome. To facilitate distinguishing these entities, the designation of "familial colorectal cancer type X" is suggested to describe this type of familial aggregation of colorectal cancer.

Adaptor Proteins, Signal Transducing↗

PubMed2005

Genetic counseling outcomes: perceived risk and distress after counseling for hereditary colorectal cancer.

Genetic counseling may turn risk information into cancer prevention behavior by modifying health beliefs and cancer-related distress. We assessed the effect of genetic counseling on these factors in 101 adult first-degree-relatives of colorectal cancer patients from families with known or suspected hereditary nonpolyposis colorectal cancer. Before counseling and once afterward, subjects completed self-report measures of perceived lifetime risk and cancer-distress. Most persons overestimated their cancer risk, and higher perceived risk was associated with believing that colorectal cancer cannot be prevented. Individual perceived risk changed after counseling, although mean perceived risk was unchanged. After adjusting for baseline risk, older persons and those with higher estimated objective cancer risk had larger postcounseling decreases. Distress after counseling was positively correlated with baseline distress and anxiety symptoms, and inversely correlated with tolerance for ambiguity. The findings suggest counseling interventions that should increase the likelihood of screening and offer hypotheses for future research.

Adaptation, Psychological↗

PubMed2005

Probability of pancreatic cancer following diabetes: a population-based study.

BACKGROUND & AIMS: Although diabetes occurs frequently in pancreatic cancer, the value of new-onset diabetes as a marker of underlying pancreatic cancer is unknown. METHODS: We assembled a population-based cohort of 2122 Rochester, Minnesota, residents age > or =50 years who first met standardized criteria for diabetes between January 1, 1950, and December 31, 1994, and identified those who developed pancreatic cancer within 3 years of meeting criteria for diabetes. We compared observed rates of pancreatic cancer with expected rates based on the Iowa Surveillance Epidemiology and End Results registry. In a nested case control study, we compared body mass index (BMI) and smoking status in diabetes subjects with and without pancreatic cancer. RESULTS: Of 2122 diabetic subjects, 18 (0.85%) were diagnosed with pancreatic cancer within 3 years of meeting criteria for diabetes; 10 of 18 (56%) were diagnosed <6 months after first meeting criteria for diabetes, and 3 were resected. The observed-to-expected ratio of pancreatic cancer in the cohort was 7.94 (95% CI, 4.70-12.55). Compared with subjects without pancreatic cancer, diabetic subjects with pancreatic cancer were more likely to have met diabetes criteria after age 69 (OR = 4.52, 95% CI, 1.61-12.74) years but did not differ significantly with respect to BMI values (29.2 +/- 6.8 vs 26.5 +/- 5.0, respectively). A larger proportion of those who developed pancreatic cancer were ever smokers (92% vs 69%, respectively), but this did not reach statistical significance. CONCLUSIONS: Approximately 1% of diabetes subjects aged > or =50 years will be diagnosed with pancreatic cancer within 3 years of first meeting criteria for diabetes. The usefulness of new-onset diabetes as marker of early pancreatic cancer needs further evaluation.

Age Distribution↗

PubMed2005

Changing trends in the incidence, stage, survival, and screen-detection of colorectal cancer: a population-based study.

BACKGROUND & AIMS: Colorectal cancer (CRC) screening has been advocated increasingly during the past 2 decades, but there is little direct evidence that it has affected cancer incidence or presentation at the population level. This study assessed concurrent trends in CRC incidence, presentation, survival, mortality, and polypectomies in Olmsted County, Minnesota. METHODS: Longitudinal observational study was conducted of all Olmsted County residents with colorectal adenocarcinoma first diagnosed in 1980-1999. RESULTS: Altogether, 889 invasive CRCs were diagnosed among Olmsted County residents from 1980 through 1999. Annual age- and sex-adjusted CRC incidence rates decreased significantly during this period (P = .02) with a 23% decline from 60 per 100,000 in 1980-1984 to 46 per 100,000 in 1995-1999. This was primarily accounted for by a 40% reduction in left-sided CRC (P < .001). The incidence of right-sided CRC remained unchanged, but the proportion of right-sided CRC increased from 46% to 58%. Cancer stage shifted downward, and survival improved over time. The overall proportion of screen-detected CRC rose from 8% to 17%. Annual adjusted adenomatous polypectomy rates increased dramatically from 86 to 320 per 100,000 (P < .001). CONCLUSIONS: The incidence of CRC in Olmsted County has declined in recent years. An impact of screening is suggested by the observed upward trend in screen-detected cases, a favorable stage shift, and a concurrent rise in polypectomy rates. However, the incidence of right-sided cancer remains unaltered and might be less affected by historically used screening interventions. Most CRCs still present symptomatically, and more effective population screening is needed.

Age Distribution↗

PubMed2005

Genomics, genetic epidemiology, and genomic medicine.

Medical science is on the threshold of unparalleled progress as a result of the advent of genomics and related disciplines. Human genomics, the study of structure, function, and interactions of all genes in the human genome, promises to improve the diagnosis, treatment, and prevention of disease. This opportunity is the result of the recent completion of the Human Genome Project. It is anticipated that genomics will bring to physicians a powerful means to discover hereditary elements that interact with environmental factors leading to disease. However, the expected transformation toward genomics-based medicine will occur over decades. It will require efforts of many scientists and physicians to begin now to sort out the vast amounts of information in the human genome and translate it to meaningful applications in clinical practice. Meanwhile, practicing physicians and health professionals need to be trained in the principles, applications, and limitations of genomics and genomic medicine. Only then will we be in a position to benefit patients, which is the ultimate goal of accelerating scientific progress in medicine. In this inaugural article, we introduce and discuss concepts, facts, and methods of genomics and genetic epidemiology that will be drawn on in the forthcoming topics of the clinical genomics series.

Chromosome Mapping↗

PubMed2005

The genetics of irritable bowel syndrome.

Because of the heterogeneity in symptoms and diagnostic findings, patients with irritable bowel syndrome (IBS) remain a challenge to treat and to study. This difficulty stems from lack of understanding of the pathophysiology of this disorder. Environmental factors likely play an important role in the pathogenesis and clinical manifestations of IBS. Several recent studies suggest a genetic basis for IBS, either in etiology or predicting response to therapy. Because of interest in studying the genetic contributors to this and other functional gastrointestinal disorders, we review the literature on genetic risk factors that might explain the familial clustering of IBS. Familial aggregation studies and twin studies suggest a modest contribution of genetics to the development of IBS. Pharmacogenomic and association studies provide stronger, although far from conclusive, evidence for genetic variants that affect expression of IBS. Together, these studies suggest that a multidisciplinary approach with clinical and psychological tools, epidemiologic methods, and genetic techniques might help elucidate the molecular components leading to the common symptoms of IBS and result in better treatments for those with IBS.

Humans↗

PubMed2004

Prospective risk of pancreatic cancer in familial pancreatic cancer kindreds.

Individuals with a family history of pancreatic cancer have an increased risk of developing pancreatic cancer. Quantification of this risk provides a rational basis for cancer risk counseling and for screening for early pancreatic cancer. In a prospective registry-based study, we estimated the risk of pancreatic cancer in individuals with a family history of pancreatic cancer. Standardized incidence ratios were calculated by comparing the number of incident pancreatic cancers observed with those expected using Surveillance, Epidemiology and End Results (SEER) rates. Familial pancreatic cancer (FPC) kindreds were defined as kindreds having at least one pair of first-degree relatives with pancreatic cancer, and sporadic pancreatic cancer (SPC) kindreds as families without such an affected pair. Nineteen incident pancreatic cancers developed among 5,179 individuals from 838 kindreds (at baseline, 370 FPC kindreds and 468 SPC kindreds). Of these 5,179 individuals, 3,957 had at least one first-degree relative with pancreatic cancer and contributed 10,538 person-years of follow-up. In this group, the observed-to-expected rate of pancreatic cancer was significantly elevated in members of FPC kindreds [9.0; 95% confidence interval (CI), 4.5-16.1], but not in the SPC kindreds (1.8; 95% CI., 0.22-6.4). This risk in FPC kindreds was elevated in individuals with three (32.0; 95% CI, 10.2-74.7), two (6.4; CI, 1.8-16.4), or one (4.6; CI, 0.5-16.4) first-degree relative(s) with pancreatic cancer. Risk was not increased among 369 spouses and other genetically unrelated relatives. Risk was higher in smokers than in nonsmokers. Individuals with a strong family history of pancreatic cancer have a significantly increased risk of developing pancreatic cancer.

Adult↗

PubMed2004

Role and limitations of epidemiology in establishing a causal association.

Cancer risk assessment is one of the most visible and controversial endeavors of epidemiology. Epidemiologic approaches are among the most influential of all disciplines that inform policy decisions to reduce cancer risk. The adoption of epidemiologic reasoning to define causal criteria beyond the realm of mechanistic concepts of cause-effect relationships in disease etiology has placed greater reliance on controlled observations of cancer risk as a function of putative exposures in populations. The advent of molecular epidemiology further expanded the field to allow more accurate exposure assessment, improved understanding of intermediate endpoints, and enhanced risk prediction by incorporating the knowledge on genetic susceptibility. We examine herein the role and limitations of epidemiology as a discipline concerned with the identification of carcinogens in the physical, chemical, and biological environment. We reviewed two examples of the application of epidemiologic approaches to aid in the discovery of the causative factors of two very important malignant diseases worldwide, stomach and cervical cancers. Both examples serve as paradigms of successful cooperation between epidemiologists and laboratory scientists in the pursuit of the understanding of cancer etiology.

Carcinogens↗

PubMed2004

Screening for pancreatic neoplasia in high-risk individuals: an EUS-based approach.

BACKGROUND & AIMS: Relatives of patients with pancreatic cancer and persons with certain inherited syndromes are at increased risk for developing pancreatic cancer. We prospectively evaluated the feasibility of screening for pancreatic neoplasia in high-risk individuals. METHODS: Individuals from familial pancreatic cancer kindreds and a patient with Peutz-Jeghers syndrome underwent screening endoscopic ultrasound (EUS). If the EUS was abnormal, EUS-guided fine-needle aspiration, endoscopic retrograde cholangiopancreatography (ERCP), and spiral computed tomography (CT) were performed. Patients with abnormalities suggesting neoplasia had surgery. RESULTS: Thirty-eight patients were studied; 31 (mean age, 58 yr; 42% men) from kindreds with > or =3 affected with pancreatic cancer; 6 from kindreds with 2 affected relatives, 1 was a patient with Peutz-Jeghers syndrome. None had symptoms referable to the pancreas or suggestive of malignancy. Six pancreatic masses were found by EUS: 1 invasive ductal adenocarcinoma, 1 benign intraductal papillary mucinous neoplasm, 2 serous cystadenomas, and 2 nonneoplastic masses. Hence, the diagnostic yield for detecting clinically significant pancreatic neoplasms was 5.3% (2 of 38). The 1 patient with pancreatic cancer was treated and still is alive and disease-free >5 years after surgery. EUS changes similar to those associated with chronic pancreatitis were found, which were more common in patients with a history of regular alcohol intake (P = 0.02), but also occurred in patients who did not consume alcohol. Screening also led to a new diagnosis and treatment of symptomatic upper-gastrointestinal conditions in 18.4% of patients. CONCLUSIONS: EUS-based screening of asymptomatic high-risk individuals can detect prevalent resectable pancreatic neoplasia but false-positive diagnoses also occur.

Age Distribution↗