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101.
Association of SULT1A1 phenotype and genotype with prostate cancer risk in African-Americans and Caucasians. 总被引:3,自引:0,他引:3
Susan Nowell D Luke Ratnasinghe Christine B Ambrosone Suzanne Williams Terri Teague-Ross Lyndsey Trimble Gail Runnels Alindria Carrol Bridgett Green Angie Stone Don Johnson Graham Greene Fred F Kadlubar Nicholas P Lang 《Cancer epidemiology, biomarkers & prevention》2004,13(2):270-276
Exposure to heterocyclic amines may increase prostate cancer risk. Human sulfotransferase 1A1 (SULT1A1) is involved in the bioactivation of some dietary procarcinogens, including the N-hydroxy metabolite of the food-borne heterocyclic amine, 2-amino-1-methyl-6-phenylimidazo(4,5-b) pyridine. This study compares a polymorphism in the SULT1A1 gene, SULT1A1 enzyme activity, meat consumption, and the risk of prostate cancer in a population based case-control study. Prostate cancer patients (n = 464) and control individuals (n = 459), frequency matched on age and ethnicity, provided informed consent, answered a survey, and provided a blood sample. Platelets were isolated for phenotype analysis, and DNA was isolated from lymphocytes for genotype determination. Meat consumption was assessed using a dietary questionnaire. Caucasians homozygous for the SULT1A1*1 high activity allele were at increased risk for prostate cancer [odds ratio (OR), 1.68; 95% confidence interval (CI), 1.05-2.68] compared with individuals homozygous for the low-activity allele. The association between SULT1A1 genotype and prostate cancer risk in African-Americans did not reach significance (OR, 1.60; 95% CI, 0.46-5.62). When SULT1A1 activity was considered, there was a strong association between increased SULT1A1 activity and prostate cancer risk in Caucasians (OR, 3.04; 95% CI, 1.8-5.1 and OR, 4.96; 95% CI, 3.0-8.3, for the second and third tertiles of SULT1A1 activity, respectively) compared with individuals in the low enzyme activity tertile. A similar association was also found in African-American patients, with ORs of 6.7 and 9.6 for the second and third tertiles of SULT1A1 activity (95% CI, 2.1-21.3 and 2.9-31.3, respectively). When consumption of well-done meat was considered, there was increased risk of prostate cancer (OR, 1.42; 95% CI, 1.01-1.99 and OR, 1.68; 95% CI, 1.20-2.36 for the second and third tertiles, respectively). When SULT1A1 activity was stratified by tertiles of meat consumption, there was greater risk of prostate cancer in the highest tertile of meat consumption. These results indicate that variations in SULT1A1 activity contributes to prostate cancer risk and the magnitude of the association may differ by ethnicity and be modified by meat consumption. 相似文献
102.
Alcohol exposure and breast cancer: results of the women's contraceptive and reproductive experiences study. 总被引:2,自引:0,他引:2
Jill A McDonald Michele G Mandel Polly A Marchbanks Suzanne G Folger Janet R Daling Giske Ursin Michael S Simon Leslie Bernstein Brian L Strom Sandra A Norman Kathleen E Malone Linda K Weiss Ronald T Burkman Anita L Weber Robert Spirtas 《Cancer epidemiology, biomarkers & prevention》2004,13(12):2106-2116
OBJECTIVES: To explore associated biological outcomes and clarify the role of timing of exposure in the alcohol-breast cancer relationship.METHODS: In a population-based study of 4,575 women ages 35 to 64 years diagnosed with invasive breast cancer between 1994 and 1998 and 4,682 controls, we collected details of lifetime alcohol use and factors that could confound or modify the alcohol-breast cancer relationship. We used conditional logistic regression to compute the odds of breast cancer among drinkers relative to nondrinkers at all ages and at ages 35 to 49 and 50 to 64 years separately.RESULTS: Recent consumption (at reference age minus two) of >/=7 drinks per week was associated with increased risk [odds ratio (OR), 1.2; 95% CI, 1.01-1.3] and evidence of dose response was observed. Most of the excess was observed among women ages 50-64 years (OR 1.3; 95% CI, 1.1-1.6), although the test for age interaction was not statistically significant. Exposure later in life seemed more important than early exposure. Excess breast cancer associated with recent consumption was restricted to localized disease. When outcome was examined according to tumor hormone receptor status, highest risks were observed for estrogen receptor-positive/progesterone receptor-negative tumors (OR 1.6; 95% CI, 1.2-2.3).CONCLUSIONS: The effect of timing of alcohol exposure on breast cancer risk is complicated and will require additional study focused on this one issue. Further work is needed to explain how alcohol exposure, sex hormones, and tumor receptor status interact. 相似文献
103.
104.
[18F] FDG PET in Gastric Non-Hodgkin's Lymphoma 总被引:1,自引:0,他引:1
Miriam Rodriguez H kan Ahlstr m Anders Sundí n Suzanne Rehn Christer Sundstr m Hans Hagberg Bengt Glimelius 《Acta oncologica (Stockholm, Sweden)》1997,36(6):577-584
The possibility of using [18F] FDG PET for assessment of tumor extension in primary gastric non-Hodgkin's lymphoma (NHL) was studied in 8 patients (6 high-grade and 2 Iow-grade, one of the MALT type) and in a control group of 7 patients (5 patients with NHL without clinical signs of gastric involvement, 1 patient with NHL and benign gastric ulcer and 1 patient with adenocarcinoma of the stomach). All patients with gastric NHL and the two with benign gastric ulcer and adenocarcinoma, respectively, underwent endoscopy including multiple biopsies for histopathological diagnosis. All patients with high-grade and one of the two with low-grade NHL and the patient with adenocarcinoma displayed high gastric uptake of [18F] FDG corresponding to the pathological findings at endoscopy and/or CT. No pathological tracer uptake was seen in the patient with low-grade gastric NHL of the MALT type. In 6/8 patients with gastric NHL, [18F] FDG PET demonstrated larger tumor extension in the stomach than was found at endoscopy, and there was high tracer uptake in the stomach in two patients who were evaluated as normal on CT. [18F] FDG PET correctly excluded gastric NHL in the patient with a benign gastric ulcer and in the patients with NHL without clinical signs of gastric involvement. Although the experience is as yet limited, [18F] FDG PET affords a novel possibility for evaluation of gastric NHL and would seem valuable as a complement to endoscopy and CT in selected patients, where the technique can yield additional information decisive for the choice of therapy. 相似文献
105.
Suzanne M. Jacques Faisal Qureshi Barbara J. Doss Adnan Munkarah 《Pediatric and developmental pathology》1998,1(5):380-387
Choriocarcinoma arising in the placenta, or intraplacental choriocarcinoma, has seldom been reported, particularly in the
absence of maternal metastases. Reluctance to diagnose choriocarcinoma in the presence of chorionic villi can delay diagnosis;
however, timely diagnosis of choriocarcinoma is prognostically important, both for the mother and infant. We report the clinicopathologic
findings in five mothers and infants in whom choriocarcinoma was identified in the placenta. None of the mothers had a history
of gestational trophoblastic disease in previous pregnancies. Three placentas were similar with a single small lesion grossly
suggesting a small infarct; microscopically these consisted of infarcted areas surrounded by choriocarcinoma. These three
mothers were unusual in that none had metastatic choriocarcinoma; two were treated with chemotherapy and remained disease-free;
the third was lost to follow-up shortly following delivery. The remaining two mothers had known pulmonary metastases at time
of delivery. One of these latter two placentas contained a large marginal lesion microscopically identified as choriocarcinoma.
The fifth placenta had rare microscopic foci of choriocarcinoma, and sheets of necrotic choriocarcinoma were identified in
“blood clot” submitted with the placenta. In four of the five cases the choriocarcinoma appeared to be arising from otherwise
normal chorionic villi, and in no case was there invasion of the villous stroma. All of the infants survived, and none had
evidence of choriocarcinoma. These cases support the concept that choriocarcinoma associated with otherwise normal pregnancy
arises in the placenta and may be more common than reported.
Received August 11, 1997; accepted December 8, 1997. 相似文献
106.
Background : Dry eye is a common complication of LASIK surgery. Our clinical impression was that post‐LASIK dry eye was more problematic for our Asian patients. The aim of this study was to determine if dry eye after LASIK is more prevalent, more sustained and more severe in Asian eyes compared with Caucasian eyes. Methods : This study was based on a retrospective analysis of a clinical database. Data (n = 932 eyes, 932 patients) was collected before and after (week 2 and months 1, 3 and 6) LASIK surgery. Patients were defined as Asian if both parents were of East Asian ethic origin. Assessments included dry eye symptoms, ocular surface staining, tear volume, tear secretion, tear film stability and corneal sensation. Results : Asian eyes had greater ocular surface staining, poorer tear film stability and lower tear volume before LASIK and at all times after LASIK. Dry eye symptoms occurring ‘often or constantly’ were more prevalent at all time points after LASIK in Asian eyes. Chronic dry eye persisting six months or more after LASIK was diagnosed in 28 per cent of Asian eyes and 5 per cent of Caucasian eyes (p < 0.001). Asian patients with chronic dry eye were predominantly female, reported dry eye symptoms, had greater ocular surface staining and lower tear secretion, stability and volume before surgery. After LASIK, Asian eyes had a slower return to pre‐operative values for ocular surface staining, tear volume and corneal sensation. Discussion : The risk of chronic dry eye after LASIK was significantly higher in Asian eyes. Contributing factors could include racial differences in eyelid and orbital anatomy, tear film parameters and blinking dynamics and higher attempted refractive corrections in Asian eyes. 相似文献
107.
Gerald Gartlehner Suzanne L West Kathleen N Lohr Leila Kahwati Jana G Johnson Russell P Harris Lynn Whitener Christiane E Voisin Sonya Sutton 《International journal for quality in health care》2004,16(5):399-406
BACKGROUND: An important concern for developers of clinical practice guidelines is how best to determine when guidelines require updating to ensure they remain current and evidence based. Because of the high costs associated with updating guidelines, recent attention has focused on approaches that can reliably assess the extent of updating required. Recently, Shekelle and colleagues proposed a model of limited literature searches with modest expert involvement as a way to reduce the cost and time requirements for assessing whether a guideline needs updating. METHODS: The main objective of this study was to compare the Shekelle et al. assessment model (review approach) and a conventional process using typical systematic review methods (traditional approach) in terms of comprehensiveness and effort. We modeled the review approach on that by Shekelle and colleagues but refined it iteratively over three phases to achieve greater efficiency. Using both methods independently, we assessed the need to update six topics from the 1996 Guide to Clinical Preventive Services from the US Preventive Services Task Force. Main outcomes included completeness of study identification, importance of missed studies and the effort involved. RESULTS: Although the review approach identified fewer eligible studies than the traditional approach, none of the studies missed was rated as important by task force members acting as liaisons to the project with respect to whether the topic required an update. On average, the review approach produced substantially fewer citations to review than the traditional approach. The effort involved and potential time saving depended largely on the scope of the topic. CONCLUSIONS: The revised review approach provides an efficient and acceptable method for judging whether a guideline requires updating. 相似文献
108.
In this study, WHOQOL survey data obtained from 4802 sick and well participants in 15 countries were used to investigate the relationship between judgements about different dimensions of quality of life (QOL) (core scores) and the importance attributed to them. As a theoretical framework, we applied the WHOQOL Group's (1995) definition of QOL which indicates that those who report the very poorest QOL will be least likely to have met their own '...goals, expectations, standards and concerns'. Those with the poorest QOL would therefore be expected to show the biggest difference between core and importance scores, and therefore be distinguishable from respondents whose QOL was poor, better or best. The main effects from overall analyses confirmed that those reporting the largest negative differences tended to report the poorest QOL and also attached a high degree of importance to these dimensions. Evidence for a decreasing differential across the four groups (poorest to best) was confirmed for the majority (18) of facets. However facet level analyses comparing groups with different levels of QOL showed that only five facets distinguished those with the poorest QOL from those whose QOL was poor, so the theory is not well supported. Furthermore the contribution of core-importance facet differences reduced the overall prediction of QOL, when compared with a regression of core scores alone. Importance information about specific facets may have limited potential to be used alongside the main instrument to identify areas of the poorest QOL for clinical or social action. 相似文献
109.
Luis F Porrata Morie A Gertz Mark R Litzow Martha Q Lacy Angela Dispenzieri David J Inwards Stephen M Ansell Ivanna N M Micallef Dennis A Gastineau Michele Elliott William J Hogan Suzanne R Hayman Ayalew Tefferi Svetomir N Markovic 《Clinical cancer research》2005,11(3):1210-1218
PURPOSE: Absolute lymphocyte count recovery at day 15 (ALC-15) post-autologous stem cell transplantation (ASCT) is a powerful prognostic indicator for survival for multiple hematologic malignancies and metastatic breast cancer. The relationship of ALC-15 with clinical outcomes in primary systemic amyloidosis is unknown. EXPERIMENTAL DESIGN: We evaluated 145 consecutive patients with primary systemic amyloidosis who underwent ASCT at the Mayo Clinic from 1996 to 2003. The ALC-15 threshold was set at 500 cells/microL based on our previous observations. RESULTS: The median patient follow-up was 22 months (range, 3-87 months). Higher hematologic complete response was observed in patients with an ALC-15 > or = 500 cells/microL compared with patients with an ALC-15 < 500 cells/microL (41% versus 21%, P < 0.0008, respectively). The median overall survival and progression-free survival times were significantly better for the 59 patients that achieved an ALC-15 > or = 500 cells/microL compared with 86 patients with ALC-15 < 500 cells/microL (not reached versus 53 months, P < 0.0003 and not reached versus 27 months, P < 0.0001, respectively). Multivariate analysis showed ALC-15 to be an independent prognostic factor for overall survival and progression-free survival. CONCLUSIONS: ALC-15 > or = 500 cells/microL is associated with significantly improved clinical outcomes following ASCT in patients with primary systemic amyloidosis. 相似文献
110.
Biallelic deletions in INK4 in cutaneous melanoma are common and associated with decreased survival. 总被引:5,自引:0,他引:5
Eva Grafstr?m Suzanne Egyházi Ulrik Ringborg Johan Hansson Anton Platz 《Clinical cancer research》2005,11(8):2991-2997
PURPOSE: Both the retinoblastoma and p53 pathways are often genetically altered in human cancers and their complex regulation is in part mediated by the three gene products p16, p14(ARF), and p15 of the INK4 locus on chromosome 9p21. Partial or complete biallelic deletions of the INK4 locus have been recognized in a variety of malignant tumors, including malignant melanoma. We have in the present study measured the frequency of INK4 deletions in a large number of melanoma metastases and determined their association with clinicopathologic variables and survival data. EXPERIMENTAL DESIGN: Quantitative real-time PCR, as well as fluorescence-based fragment analysis, has been used to perform measurements of the relative allelic concentrations of the INK4 genes in 112 human melanoma tumor samples from 86 patients. RESULTS: Thirty-eight of 86 melanoma patients (44%) had metastases with biallelic losses in INK4. Ten of 20 patients with multiple metastases showed similar deletion patterns in all analyzed tumors. There was no significant association between any of the clinicopathologic variables and loss of INK4. However, loss of INK4 had an adverse effect on median survival from time of diagnosis. Patients with tumors with diploid INK4 had a median survival of 142 months, whereas those with monoallelic or biallelic loss in INK4 had a median survival of only 47 months (P = 0.006). CONCLUSIONS: Our results point to homozygous deletions in the INK4 region as being one of the most common genetic alterations in malignant cutaneous melanoma. INK4 deletions are associated with an adverse prognosis. 相似文献