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The 825C>T polymorphism of the G-protein beta-3 subunit gene (GNB3) and breast cancer.

The 825C>T polymorphism in the gene for the G-protein beta3 subunit (GNB3) has been linked to the occurrence of a splice variant of GNB3 and distinct cellular and metabolic features and may be associated with malignant disease. 500 patients with histologically confirmed breast cancer and 500 female age-matched healthy control subjects were genotyped for the GNB3 polymorphism to analyze its role for breast cancer. Prevalences of GNB3 CC, CT and TT genotypes were similar among patients (49.7, 39.8, 10.5%) and controls (50.1, 42.4, 7.5%, P = 0.25). The GNB3 genotype was furthermore not linked to tumor size, histological grading, estrogen or progesterone receptor status and age at diagnosis. In an exploratory analysis, carriage of a 825-T allele was associated with a longer metastasis-free period in patients with primary low-grade breast cancer, but not in those with primary high-grade breast cancer (Cox regression, P = 0.025). We conclude that the GNB3 825C>T polymorphism does not appear to be associated with breast cancer risk, but may influence development of metastasis in low-grade tumors.

Adult↗

Do 40% of patients resected for barrett esophagus with high-grade dysplasia have unsuspected adenocarcinoma?

Results of studies conducted in the last 2 decades suggest that the detection of high-grade dysplasia in patients with Barrett esophagus is the harbinger of a synchronous adenocarcinoma, which remains undetected even by rigorous biopsy protocols but is discovered during resection of the esophagus. The reported prevalence of synchronous carcinomas ranges from 0% to 75%. Other researchers maintain that appropriate surveillance programs can be used to detect carcinomas at a curable stage and to prevent unnecessary esophagectomies. Both logistical difficulties and potential methodological pitfalls have plagued many studies designed to investigate this issue. A large multicenter study that would stratify participants for hitherto unexplored variables (eg, age, gender, and ethnic background) may be required before the 40% occult cancer prevalence can be either confirmed or refuted. However, the large scale needed for such a study to provide reliable data and new developments in endoscopic imaging (eg, magnification endoscopy and optical coherence tomography) and endoscopic therapy (eg, mucosectomy) are likely to make such a study both ethically unacceptable and logistically and financially unfeasible. Future research should utilize the combination of new endoscopic technologies with the continuing search for validated biomarkers that help predict the biological behavior of Barrett epithelium in individual patients, with a particular focus on the possible development of preneoplastic and neoplastic lesions. Pathologists who chose to shift their focus from the traditional morphological investigation of dysplasia to the search for usable biomarkers can position themselves at the center of innovative research projects that could radically modify the management of patients with Barrett esophagus.

Adenocarcinoma↗

Estimated incidence and prevalence of female breast cancer in Italian regions.

Female breast cancer incidence and prevalence in Italy have been estimated by region and vast areas from population-based survival data of breast cancer patients and 1970-1987 specific mortality data using a mathematical model. Italian age-standardized incidence rates (ASR) for 1987 range from 70 to 90 per 100,000 women-year in the Northern regions, 55 to 73 in the Center, and 45 to 72 in the South. Overall, the ASR is about 80 in the North, 70 in the Center and 60 in the South. In the absence of competitive mortality, breast cancer cumulative risk in the 0-74 years life span is about 7 women out of 100 in the North, 6 in the Center and 5 in the South. The decreasing risk pattern from North to Center then South appears less evident when under 45 age-specific rates are considered. Very high levels for young age-groups are present both in the North (Liguria and Emilia Romagna) and South (Sardinia and Apulia). The incidence pattern by age differs from region to region and over the considered period, suggesting that a birth-cohort effect is crossing the whole country. Using to model, it can be estimated that the risk by cohort increases from the generations born at the beginning of the century to those born in the 40s, after which, for subsequent generations, it has been decreasing in all the considered areas and is similar in the North and South. We can infer that for the whole country the incidence will increase up to the years 2000-2010 when those birth-cohorts at higher risk will also be at higher risk for age. In 1987, about 250,000 Italian women had a present or past history of breast cancer: for the 1970-1987 period, prevalence has increased by approximately 5,500 cases per year.

Age Factors↗

Breast density and parenchymal patterns as markers of breast cancer risk: a meta-analysis.

Mammographic features are associated with breast cancer risk, but estimates of the strength of the association vary markedly between studies, and it is uncertain whether the association is modified by other risk factors. We conducted a systematic review and meta-analysis of publications on mammographic patterns in relation to breast cancer risk. Random effects models were used to combine study-specific relative risks. Aggregate data for > 14,000 cases and 226,000 noncases from 42 studies were included. Associations were consistent in studies conducted in the general population but were highly heterogeneous in symptomatic populations. They were much stronger for percentage density than for Wolfe grade or Breast Imaging Reporting and Data System classification and were 20% to 30% stronger in studies of incident than of prevalent cancer. No differences were observed by age/menopausal status at mammography or by ethnicity. For percentage density measured using prediagnostic mammograms, combined relative risks of incident breast cancer in the general population were 1.79 (95% confidence interval, 1.48-2.16), 2.11 (1.70-2.63), 2.92 (2.49-3.42), and 4.64 (3.64-5.91) for categories 5% to 24%, 25% to 49%, 50% to 74%, and > or = 75% relative to < 5%. This association remained strong after excluding cancers diagnosed in the first-year postmammography. This review explains some of the heterogeneity in associations of breast density with breast cancer risk and shows that, in well-conducted studies, this is one of the strongest risk factors for breast cancer. It also refutes the suggestion that the association is an artifact of masking bias or that it is only present in a restricted age range.

Breast Neoplasms↗

Correlates of screening mammography in a family practice setting.

The medical records of 243 asymptomatic women aged 50 years or older were reviewed at a community-based family practice center to determine the proportion who had been referred for a screening mammogram and to identify correlates of mammography referral. Patient demographic characteristics, breast cancer risk factors, and characteristics of past patient-physician encounters were considered. Between July 1, 1981, and July 1, 1987, 40 (16 percent) of the women had received a mammography referral from their currently assigned physician. All but two of the women had actually obtained the mammogram. The primary predictors of mammography referral were the known risk factors for breast cancer: a family history of breast cancer (prevalence rate ratio [PRR] = 9.3, P = .001) and a history of benign breast disease (PRR = 7.9, P = .002). Other predictors included having a Papanicolaou test performed by the current physician (PRR = 4.1, P = .03), having a test for stool occult blood returned by the patient (PRR = 10.2, P = .003), having been instructed in smoking cessation by the current physician (PRR = 10.0, P = .05), and, possibly, being a former smoker (PRR = 4.6, P = .09). Patient demographic characteristics, other known breast cancer risk factors (age, obesity, alcohol use, and pregnancy history), and the sex of the physician were not predictive.

Aged↗

Weight loss in overweight adults and the long-term risk of hypertension: the Framingham study.

BACKGROUND: Few studies address long-term effects of weight loss on risk of incident hypertension among overweight adults. METHODS: We evaluated weight loss among 623 overweight (body mass index [calculated as weight in kilograms divided by the square of height in meters] >/=25) middle-aged (aged 30-49 years) and 605 overweight older (aged 50-65 years) adults in Framingham, Mass. Subjects were classified first according to amount of weight lost over 4 years: (1) weight changed by less than 1.8 kg (stable weight), (2) lost 1.8 to less than 3.6 kg, (3) lost 3.6 to less than 6.8 kg, and (4) lost 6.8 kg or more. We also classified weight loss according to whether it was sustained during the next 4 years. RESULTS: After adjusting for age, sex, education, baseline body mass index, height, activity, smoking, and alcohol intake, weight loss of 6.8 kg or more led to a 21% to 29% reduction in long-term hypertension risk. After adjusting for cancer or cardiovascular disease occurring during follow-up, weight loss of 6.8 kg or more led to a 28% reduction in risk (relative risk [95% confidence interval], 0.72 [0.49-1.05]) for middle-aged adults and a 37% reduction (0.63 [0.42-0.95]) for older adults. Sustained weight loss led to a 22% reduction in hypertension risk (0.78 [0.60-1.03]) among middle-aged and a 26% reduction (0.74 [0.56-0.97]) in older adults. This risk reduction was strengthened by adjustment for prevalent cancer or cardiovascular disease during follow-up. CONCLUSION: A modest weight loss, particularly when sustained, substantially lowers the long-term risk of hypertension in overweight adults.

Adult↗

Rising incidence of breast cancer after completion of the first prevalent round of the breast cancer screening programme.

OBJECTIVES: After completion of the prevalent screening round of the breast cancer screening programme in Limburg, The Netherlands, incidences started rising once again. This increase was contrary to expectations, which had predicted a slightly higher, but stable, incidence after the first screening round. The trends in incidence were studied to find explanations for the observed rise in incidence. SETTING: Breast cancer screening programme in mid-Limburg and southern Limburg, the Netherlands. METHODS: The data files of the breast cancer screening programme and the Maastricht cancer registry were linked to evaluate the effect of breast cancer screening. Only the first primary breast tumour was included in the evaluation. RESULTS: The second peak of incidence after the prevalent screening round was 45% higher than the incidences before the start of the screening. Also, the decrease in incidence of large and node positive tumours was interrupted. Compared with national detection rates, the number of screen detected cancers was lower before 1995 and higher after that year. After 1997, incidence decreased again of all breast cancers, but also of large and node positive tumours. The incidence of node positive tumours showed large fluctuations, probably due to the introduction of the sentinel node procedure and immunohistochemistry. In 1999, incidence of large tumours and node positive tumours was 18% and 28%, respectively, lower than before the start of the screening. CONCLUSIONS: An increase in the background incidences and improved detection in the screening programme most likely explain this trend. The improved detection after 1995, and the lower than desirable decrease in large tumours, indicate that the screening performance was not optimal before 1996. The incidence of node positive tumours cannot be used any more as an indicator of the success of the screening programme because of detection bias.

Aged↗

A high prevalence of antibody to the hepatitis C virus in patients with hepatocellular carcinoma in Japan.

In Japan, hepatocellular carcinoma (HCC) is one of the most prevalent cancers, with a reported fatality rate showing a consistent and significant increase in the last decade. At most, only 25% of HCC cases are positive for the hepatitis B surface antigen (HBsAg). To investigate a potential role for hepatitis C virus (HCV) in the development of HCC, sera from 105 HBsAg-negative HCC patients were collected from five districts of Japan and assayed for antibody to HCV antigen (HCVAb). A large number of these patients (76.2%) were found to be positive for the HCVAb in comparison with the reported prevalence in sera from blood donors (1.1%). A history of blood transfusion was found in 39.6% of the cases positive for HCVAb, which was significantly different to the lower rate (4.7%) observed in HCC patients who were both positive for HBsAg and negative for HCVAb (P less than 0.001).

Blood Transfusion↗

A questionnaire to measure knowledge of and education about tumor diseases in Sweden.

BACKGROUND: The increasing incidence of cancers in Sweden can only partly be explained by the increase in length of life. The general public is largely unaware of recent progress in scientific understanding of how a normal cell can be transformed into a cancer cell. METHODS: The authors constructed a questionnaire to assess public knowledge of cancer prevalence, causation, and pathogenesis, as well as attitudes towards risk factors and possibilities of prevention. It also included demographic and life-style factors. RESULTS: Reported here is the theoretical background for the questionnaire, which is published in its entirety. The questionnaire was distributed in 1993 to a random sample of 10% of the adults in two townships in southern Sweden (n = 1,005 and 972, respectively). The response rate was 70% within two weeks, and after a reminder, 78%. CONCLUSIONS: This response indicates a high level of public interest in cancer knowledge and constitutes a good basis for further education activities.

Adolescent↗

Delay in seeking a cancer diagnosis: delay stages and psychophysiological comparison processes.

Two analyses of patient delay in seeking a medical diagnosis are considered. In the first, a model of delay is presented. Specifically, delay is comprised of four stages (appraisal, illness, behavioural and scheduling delay intervals), each governed by a conceptually distinct set of decisional and appraisal processes beginning with the initial day that an unexplained symptom is detected to the day the individual appears before a physician. The second analysis is a social psychological one of the attributions individuals draw when relating their symptoms to their expectations and knowledge about physiological bodily processes. The eight principles of Psychophysiological Comparison Theory (PCT) provide the basis for clarifying the psychological processes of symptom interpretation and appraisal. Two studies were conducted with women seeking diagnostic evaluations for prevalent cancers: breast or gynaecological tumours. Regarding the delay model, results indicated that the delay intervals were independent (i.e. uncorrelated). Also, appraisal delay constituted the majority (at least 60 per cent) of the total delay. In the test of PCT, support was found across measures of symptoms, the context in which the symptoms arose, and the inferences people made about the symptoms.

Adolescent↗

Gene-gene, gene-environment & multiple interactions in colorectal cancer.

This review comprehensively evaluates the influence of gene-gene, gene-environment and multiple interactions on the risk of colorectal cancer (CRC). Methods of studying these interactions and their limitations have been discussed herein. There is a need to develop biomarkers of exposure and of risk that are sensitive, specific, present in the pathway of the disease, and that have been clinically tested for routine use. The influence of inherited variation (polymorphism) in several genes has been discussed in this review; however, due to study limitations and confounders, it is difficult to conclude which ones are associated with the highest risk (either individually or in combination with environmental factors) to CRC. The majority of the sporadic cancer is believed to be due to modification of mutation risk by other genetic and/or environmental factors. Micronutrient deficiency may explain the association between low consumption of fruit/vegetables and CRC in human studies. Mitochondrial modulation by dietary factors influences the balance between cell renewal and death critical in colon mucosal homeostasis. Both genetic and epigenetic interactions are intricately dependent on each other, and collectively influence the process of colorectal tumorigenesis. The genetic and environmental interactions present a good prospect and a challenge for prevention strategies for CRC because they support the view that this highly prevalent cancer is preventable.

Cocarcinogenesis↗

Human papillomavirus infection in the etiology of laryngeal carcinoma.

PURPOSE OF REVIEW: One fifth of cancers worldwide are associated with viral infection. Indeed, the causal link between human papillomavirus and cervical carcinoma is so well established that it is thought to be the first necessary cause of human cancer ever identified. One of the primary aims of research in this area is to reduce cancer prevalence by vaccination. However, the role that human papillomavirus plays in carcinogenesis of the head and neck region may also have important implications for its prevention and treatment. RECENT FINDINGS: Although human papillomavirus was first identified in the larynx 20 years ago, the extent to which it is present in epithelium of the normal population is unclear. Laryngeal papillomas are the most common benign tumors in the larynx. They are associated with a small risk (3 to 7%) of malignant transformation, in which smoking and irradiation appear to be cofactors. The search for alternate risk factors for the development of laryngeal cancer, particularly in those who are nonsmokers and nondrinkers, has led to the hypothesis that human papillomavirus may have a pivotal role. Epidemiologic studies, although not conclusive, strongly suggest its involvement in the etiology of a subset of laryngeal carcinomas. Recent molecular evidence supports this. SUMMARY: An adequately powered, multicenter case-control study is required to elucidate the full extent of this association and to examine the relation between the virus and other risk factors.

Humans↗

Evaluation of the nutritional status and tumor characteristics in premenopausal and postmenopausal breast cancer patients.

Evaluation of the nutritional status, fat tissue distribution, and tumor characteristics was carried out in patients with primary breast cancer. The patients were classified into two groups according to their menopause: premenopausal and postmenopausal. Breast cancer prevalence was considerably higher in postmenopausal patients (61%). The patients' nutritional status was shown through the body mass index. Based on this indicator, the patients were characterized as nonobese and obese. In the premenopausal group, there was no significant difference between these categories, whereas the number of obese patients was significantly higher (80%) in the postmenopausal group. The analysis of tumor parameters as related to menopause and body size did not yield any significant differences. However, the estrogen receptor content was significantly higher in postmenopausal patients (p < 0.0001). Distribution of fat tissue of the android type was higher in obese postmenopausal women than in premenopausal ones (77%). The investigation showed that the breast cancer incidence odds are 3.5 times higher in obese postmenopausal than in premenopausal patients.

Adult↗

The risk of colorectal cancer in ulcerative colitis: a meta-analysis.

BACKGROUND AND AIMS: Controversy surrounds the risk of colorectal cancer (CRC) in ulcerative colitis (UC). Many studies have investigated this risk and reported widely varying rates. METHODS: A literature search using Medline with the explosion of references identified 194 studies. Of these, 116 met our inclusion criteria from which the number of patients and cancers detected could be extracted. Overall pooled estimates, with 95% confidence intervals (CI), of cancer prevalence and incidence were obtained using a random effects model on either the log odds or log incidence scale, as appropriate. RESULTS: The overall prevalence of CRC in any UC patient, based on 116 studies, was estimated to be 3.7% (95% CI 3.2-4.2%). Of the 116 studies, 41 reported colitis duration. From these the overall incidence rate was 3/1000 person years duration (pyd), (95% CI 2/1000 to 4/1000). The overall incidence rate for any child was 6/1000 pyd (95% CI 3/1000 to 13/1000). Of the 41 studies, 19 reported results stratified into 10 year intervals of disease duration. For the first 10 years the incidence rate was 2/1000 pyd (95% CI 1/1000 to 2/1000), for the second decade the incidence rate was estimated to be 7/1000 pyd (95% CI 4/1000 to 12/1000), and in the third decade the incidence rate was 12/1000 pyd (95% CI 7/1000 to 19/1000). These incidence rates corresponded to cumulative probabilities of 2% by 10 years, 8% by 20 years, and 18% by 30 years. The worldwide cancer incidence rates varied geographically, being 5/1000 pyd in the USA, 4/1000 pyd in the UK, and 2/1000 pyd in Scandinavia and other countries. Over time the cancer risk has increased since 1955 but this finding was not significant (p=0.8). CONCLUSIONS: Using new meta-analysis techniques we determined the risk of CRC in UC by decade of disease and defined the risk in pancolitics and children. We found a non-significant increase in risk over time and estimated how risk varies with geography.

Australia↗

Free/total PSA ratio improves differentiation of benign and malignant disease of the prostate: critical analysis of two different test populations.

OBJECTIVES: To evaluate the ability of free PSA (fPSA), total PSA (tPSA), and the free/total PSA (f/t PSA) ratio to differentiate between benign prostate disease (benign prostatic hyperplasia [BPH] and no evidence of malignancy [NEM]) and prostate cancer (CaP) using two different testing populations, and to compare predictive probabilities for the two test populations. METHODS: One test population consisted of sera from 531 men with clinically well-defined and biopsy-confirmed BPH (n = 255) or CaP (n = 276), with tPSA values ranging from 2 to 20 ng/mL. All of these serum samples were retrospective and obtained from patients evaluated in academic settings before any treatment. A second test population consisted of a prospective analysis of sera obtained from 4870 men, collected by urologists throughout the United States and processed at a single pathology laboratory. All these patients had a systematic biopsy evaluated and diagnosed at the same pathology laboratory, with the diagnosis categorized as either NEM (n = 2961) or CaP (n = 1909). No additional information on concurrent disease or pre- or current treatment status was known for this test population. For both populations, two tPSA reflex range groups, 2 to 10 and 2 to 20 ng/mL, were evaluated. RESULTS: Both test populations benefited from the application of either fPSA alone or the f/t PSA ratio to differentiate benign from malignant disease (t test P value less than 0.001). The receiver operating characteristic (ROC) curve for the f/t PSA ratio had an area under the curve (AUC) of 72% for n = 531 versus 63% for n = 4870, irrespective of the tPSA reflex range. Average fPSA values demonstrated a linear correlation to a range of tPSA concentrations for both test populations. Predictive probabilities (adjusted for established cancer prevalence rates in the academic population [n = 531]) calculated using f/t PSA ratios also demonstrated their value in contrasting the performance characteristics in the two test populations. CONCLUSIONS: The fPSA and f/t PSA ratio improved the differentiation of benign disease and CaP in two different patient samples. The f/t PSA ratio demonstrated an increased sensitivity and specificity when applied to differentiate clinically well-defined BPH and CaP (n = 531). The differences in the results between the two test samples are probably attributable to the variability of the patient's disease and treatment status in the larger, less refined, community-based population. The use of predictive probabilities provides the opportunity to provide patient-specific cancer probabilities instead of using population-based specific single cutoffs.

Aged↗

Serum dioxin and cancer in veterans of Operation Ranch Hand.

We studied cancer prevalence and exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (dioxin) in veterans of Operation Ranch Hand, the Air Force unit responsible for the aerial spraying of herbicides in Vietnam from 1962 to 1971. A comparison group of Air Force veterans who served in Southeast Asia during the same period and who were not involved with spraying herbicides was included. Comparison veterans were matched to Ranch Hand veterans on age, race, and military occupation. We measured dioxin in 1987 or 1992, extrapolated the result to the time of service in Southeast Asia, and assigned each Ranch Hand veteran to Background, Low, or High exposure categories. This study had low power to detect an effect for specific or rare cancers. The risk of cancer at sites other than the skin within 20 years of service was increased in the Low (odds ratio (OR) = 3.4, 95% confidence interval (CI) 1.5-8.0) and High (OR = 2.7, 95% CI 0.9-8.0) categories, but the pattern was inconsistent with another study, suggesting that the excess risk may not have been caused by dioxin exposure. Overall, we found no consistent evidence of a dose-response gradient and no significant increase in cancer risk in the High dioxin exposure category, the subgroup of greatest a priori interest.

Environmental Exposure↗

Cost-benefit analysis of total, free/total, and complexed prostate-specific antigen for prostate cancer screening.

Refinements in prostate-specific antigen (PSA) through the use of its derivatives have augmented early detection rates of prostate cancer. However, these improvements are coupled with relatively large increases in unit cost per detected cancer. We used decision-analytic modeling to determine the most appropriate PSA derivative for population-based screening. We constructed a decision-analytic model to determine the PSA derivative with the highest cost-benefit ratio for prostate cancer screening. We defined 5 screening strategies: total PSA (tPSA) 4.0 ng/mL; free PSA/tPSA (f/tPSA) in conjunction with tPSA; and complexed PSA (cPSA) 3.8, 3.4, and 3.0 ng/mL. Prostate cancer prevalence, false-positive rates, and false-negative rates for each test strategy were calculated from a database of 2138 men. The direct costs were obtained from literature review and our department of clinical chemistry. The derivative cPSA with a positive threshold of 3.8 ng/mL was the dominant strategy. The average cost of screening was 138.93 dollars. The strategy of tPSA became dominant when the cost of cPSA was >35.00 dollars or the cost of a prostate biopsy was <67.30 dollars. To match the false-negative rate of tPSA 4.0 ng/mL, a cPSA threshold of 3.0 ng/mL is necessary (sensitivity 92.5%). At this level, the marginal cost increase over tPSA is 9.40 dollars. The dominant strategy for population-based prostate cancer screening is use of cPSA with a positive threshold of 3.8 ng/mL. The use of cPSA with a threshold of 3.0 ng/mL identifies a similar number of cancers with fewer biopsies than tPSA at 4.0 ng/mL.

Aged↗

[Cytology in the positive diagnosis and grading of prostatic cancers: which indications do remain at the time of automatic biopsies and endorectal echography?].

The diagnostic sensitivity (Se) and specificity (Sp) of fine-needle aspiration cytology (FNAC) of the prostate can be evaluated by comparing its results to a histological reference: rates of reported Se range from 65-98%, Sp being equal or superior to 95%. Published series are heterogeneous in terms of cancer prevalence, with a 25-85% proportion of histologically proven adenocarcinomas, irrespective of the anatomical stage of the disease. The overall accuracy of screening by core biopsies or FNAC is lower than 5%, and does not justify wide-scale application of these tests. In 75%, cytological assessment of the tumor grade correlates with Gleason's histological score and grade. Severe intraductal dysplasias (DIC 3) are probably involved in some of the cytological grade I cases. Ultrasonographic guidance of FNAC is not recommended in comparison with histologically obtained data. The indications for performing FNAC of the prostate should be different from those of standard biopsies: the former should be carried out on suspicious lesions revealed by digital rectal examination or ultrasonography, or in a staging attempt. FNAC should be reserved for early diagnosis of prostate cancer in patients presenting with non-specific urologic symptoms. Samples should be obtained by digitally-guided transrectal bilateral FNAC.

Biopsy↗