| 1. |
- Stattin, Pär, et al.
(author)
-
Improving the Specificity of Screening for Lethal Prostate Cancer Using Prostate-specific Antigen and a Panel of Kallikrein Markers : a Nested Case-Control Study
- 2015
-
In: European Urology. - : Elsevier. - 0302-2838 .- 1873-7560. ; 68:2, s. 207-213
-
Journal article (peer-reviewed)abstract
- Background: A disadvantage of prostate-specific antigen (PSA) for the early detection of prostate cancer (PCa) is that many men must be screened, biopsied, and diagnosed to prevent one death. Objective: To increase the specificity of screening for lethal PCa at an early stage. Design, setting, and participants: We conducted a case-control study nested within a population-based cohort. PSA and three additional kallikreins were measured in cryopreserved blood from a population-based cohort in Vasterbotten, Sweden. Of 40 379 men providing blood at ages 40, 50, and 60 yr from 1986 to 2009, 12 542 men were followed for > 15 yr. From this cohort, the Swedish Cancer Registry identified 1423 incident PCa cases, 235 with distant metastasis. Outcome measurements and statistical analysis: Risk of distant metastasis for different PSA levels and a prespecified statistical model based on the four kallikrein markers. Results and limitations: Mostmetastatic cases occurred in men with PSA in the top quartile at age 50 yr (69%) or 60 yr (74%), whereas 20-yr risk of metastasis for men with PSA below median was low (<= 0.6%). Among men with PSA > 2 ng/ml, a prespecified model based on four kallikrein markers significantly enhanced the prediction of metastasis compared with PSA alone. About half of all men with PSA > 2 ng/ml were defined as low risk by this model and had a <= 1% 15-yr risk of metastasis. Conclusions: Screening at ages 50-60 yr should focus on men with PSA in the top quartile. A marker panel can aid biopsy decision making. Patient summary: For men in their fifties, screening should focus on those in the top 10% to 25% of PSA values because the majority of subsequent cases of distant metastasis are found among these men. Testing of four kallikrein markers in men with an elevated PSA could aid biopsy decision making.
|
|
| 2. |
- Campa, Daniele, et al.
(author)
-
Genetic variability of the fatty acid synthase pathway is not associated with prostate cancer risk in the European Prospective Investigation on Cancer (EPIC)
- 2011
-
In: European Journal of Cancer. - : Elsevier. - 0959-8049 .- 1879-0852. ; 47:3, s. 420-427
-
Journal article (peer-reviewed)abstract
- A western lifestyle, characterised by low rates of energy expenditure and a high-energy diet rich in animal protein, saturated fats and refined carbohydrates, is associated with high incidence of prostate cancer in men. A high-energy nutritional status results in insulin/IGF signalling in cells, which in turn stimulates synthesis of fatty acids. We investigated whether the genetic variability of the genes belonging to the fatty acid synthesis pathway is related to prostate cancer risk in 815 prostate cancer cases and 1266 controls from the European Prospective Investigation on Cancer (EPIC). Using a tagging approach and selecting 252 SNPs in 22 genes, we covered all the common genetic variation of this pathway. None of the SNPs reached statistical significance after adjusting for multiple comparisons. Common SNPs in the fatty acid synthase pathway are not major contributors to prostate cancer risk.
|
|
| 3. |
- Dahm, Christina C., et al.
(author)
-
Fatty acid patterns and risk of prostate cancer in a case-control study nested within the European Prospective Investigation into Cancer and Nutrition
- 2012
-
In: American Journal of Clinical Nutrition. - : Elsevier BV. - 0002-9165 .- 1938-3207. ; 96:6, s. 1354-1361
-
Journal article (peer-reviewed)abstract
- Background: Fatty acids in blood may be related to the risk of prostate cancer, but epidemiologic evidence is inconsistent. Blood fatty acids are correlated through shared food sources and common endogenous desaturation and elongation pathways. Studies of individual fatty acids cannot take this into account, but pattern analysis can. Treelet transform (TT) is a novel method that uses data correlation structures to derive sparse factors that explain variation. Objective: The objective was to gain further insight in the association between plasma fatty acids and risk of prostate cancer by applying TT to take data correlations into account. Design: We reanalyzed previously published data from a case-control study of prostate cancer nested within the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort. TT was used to derive factors explaining the variation in 26 plasma phospholipid fatty acids of 962 incident prostate cancer cases matched to 1061 controls. Multiple imputation was used to deal with missing data in covariates. ORs of prostate cancer according to factor scores were determined by using multivariable conditional logistic regression. Results: Four simple factors explained 38% of the variation in plasma fatty acids. A high score on a factor reflecting a long-chain n-3 PUFA pattern was associated with greater risk of prostate cancer (OR for highest compared with lowest quintile: 1.36; 95% CI: 0.99, 1.86; P-trend = 0.041). Conclusion: Pattern analyses using TT groupings of correlated fatty acids indicate that intake or metabolism of long-chain n-3 PUFAs may be relevant to prostate cancer etiology. Am J Clin Nutr 2012;96:1354-61.
|
|
| 4. |
- Gu, Fangyi, et al.
(author)
-
Eighteen insulin-like growth factor pathway genes, circulating levels of IGF-I and its binding protein, and risk of prostate and breast cancer
- 2010
-
In: Cancer Epidemiology, Biomarkers and Prevention. - : American Association for Cancer Research. - 1055-9965 .- 1538-7755. ; 19:11, s. 2877-2887
-
Journal article (peer-reviewed)abstract
- Background: Circulating levels of insulin-like growth factor I (IGF-I) and its main binding protein, IGF binding protein 3 (IGFBP-3), have been associated with risk of several types of cancer. Heritable factors explain up to 60% of the variation in IGF-I and IGFBP-3 in studies of adult twins.Methods: We systematically examined common genetic variation in 18 genes in the IGF signaling pathway for associations with circulating levels of IGF-I and IGFBP-3. A total of 302 single nucleotide polymorphisms (SNP) were genotyped in >5,500 Caucasian men and 5,500 Caucasian women from the Breast and Prostate Cancer Cohort Consortium.Results: After adjusting for multiple testing, SNPs in the IGF1 and SSTR5 genes were significantly associated with circulating IGF-I (P < 2.1 × 10−4); SNPs in the IGFBP3 and IGFALS genes were significantly associated with circulating IGFBP-3. Multi-SNP models explained R2 = 0.62% of the variation in circulating IGF-I and 3.9% of the variation in circulating IGFBP-3. We saw no significant association between these multi-SNP predictors of circulating IGF-I or IGFBP-3 and risk of prostate or breast cancers.Conclusion: Common genetic variation in the IGF1 and SSTR5 genes seems to influence circulating IGF-I levels, and variation in IGFBP3 and IGFALS seems to influence circulating IGFBP-3. However, these variants explain only a small percentage of the variation in circulating IGF-I and IGFBP-3 in Caucasian men and women.Impact: Further studies are needed to explore contributions from other genetic factors such as rare variants in these genes and variation outside of these genes.
|
|
| 5. |
- Holmström, Benny, 1974-
(author)
-
Early diagnosis and treatment of prostate cancer : observational studies in the National Prostate Cancer Register of Sweden and the Västerbotten Intervention Project
- 2011
-
Doctoral thesis (other academic/artistic)abstract
- Prostate-specific antigen (PSA) testing has caused a steep increase in the incidence of prostate cancer, especially the incidence of localised low risk disease. In order to decrease the overdiagnosis accompanied by PSA testing, analysis of inherited genetic variants have been suggested as potential tools for clinical assessment of disease risk. With the aim of minimizing overtreatment and postpone side-effects of curative treatment for low risk prostate cancer, active surveillance, a treatment strategy with initial surveillance and deferred radical prostatectomy at the time of progression has evolved. The aim of this thesis was to study the validity of PSA (paper I) and inherited genetic variants (paper II) for early diagnosis of prostate cancer, to assess the extent of PSA testing in Sweden (paper III), and to study the safety of deferred radical prostatectomy in localised low to intermediate risk prostate cancer (paper IV). The study designs were i) case-control studies nested within the Västerbotten intervention project (paper I and II), ii) observational study in the Cancer Register of Sweden (paper III), and iii) observational study in the NPCR Follow-up study (paper IV). PSA had a high validity in predicting a prostate cancer diagnosis with an area under the receiver operating characteristics (ROC) curve of 0.86 (95% CI, 0.84 to 0.88). A combined test, including PSA, the ratio of free to total PSA, and 33 single nucleotide polymorphisms (SNPs) in a genetic risk score, increased the area under curve to 0.87 (95% CI, 0.85 to 0.89). The estimated uptake of PSA testing among men aged 55 to 69 years increased from zero to 56% between 1997 and 2007 and there were large variations in the uptake of PSA testing between counties in Sweden. After a median follow-up time of eight years there was no significant difference in presence of any one or more adverse pathology features or prostate cancer specific mortality after primary compared to deferred radical prostatectomy in localised low to intermediate risk prostate cancer. Results from these studies indicate that PSA and the hitherto identified SNPs are not suitable biomarkers in single-test prostate cancer screening. It is possible to estimate the uptake of PSA testing on a population level. Initial surveillance and deferred radical prostatectomy represent a feasible treatment strategy in localised low to intermediate risk prostate cancer.
|
|
| 6. |
- Holmström, Benny, 1974-, et al.
(author)
-
Prostate specific antigen for early detection of prostate cancer : longitudinal study
- 2009
-
In: BMJ (Clinical research ed.). - : BMJ. - 1468-5833 .- 0959-8138. ; 339, s. b3537-
-
Journal article (peer-reviewed)abstract
- OBJECTIVE: To evaluate if prostate specific antigen test attains validity standards required for screening in view of recent prostate cancer screening trial results.DESIGN: Case-control study nested in longitudinal cohort.SETTING: Västerbotten Intervention Project cohort, Umeå, Sweden.PARTICIPANTS: 540 cases and 1034 controls matched for age and date of blood draw.MAIN OUTCOME MEASURE: Validity of prostate specific antigen for prediction of subsequent prostate cancer diagnosis by record linkage to cancer registry.RESULTS: Blood samples were drawn on average 7.1 (SD 3.7) years before diagnosis. The area under the curve for prostate specific antigen was 0.84 (95% confidence interval 0.82 to 0.86). At prostate specific antigen cut-off values of 3, 4, and 5 ng/ml, sensitivity estimates were 59%, 44%, and 33%, and specificity estimates were 87%, 92%, and 95%. The positive likelihood ratio commonly considered to "rule in disease" is 10; in this study the positive likelihood ratios were 4.5, 5.5, and 6.4 for prostate specific antigen cut-off values of 3, 4, and 5 ng/ml. The negative likelihood ratio commonly considered to "rule out disease" is 0.1; in this study the negative likelihood ratios were 0.47, 0.61, and 0.70 for prostate specific antigen cut-off values of 3, 4, and 5 ng/ml. For a cut-off of 1.0 ng/ml, the negative likelihood ratio was 0.08.CONCLUSIONS: No single cut-off value for prostate specific antigen concentration attained likelihood ratios formally required for a screening test. Prostate specific antigen concentrations below 1.0 ng/ml virtually ruled out a prostate cancer diagnosis during the follow-up. Additional biomarkers for early detection of prostate cancer are needed before population based screening for prostate cancer should be introduced.
|
|
| 7. |
- Holmström, Benny, et al.
(author)
-
PSA-testet håller inte för screening: bra – men inte tillräckligt bra : [The PSA test does not hold for screening: good – but not good enough]
- 2009
-
In: Läkartidningen. - : Sveriges läkarförbund. - 0023-7205 .- 1652-7518. ; 107:7, s. 436, 438-439
-
Journal article (peer-reviewed)abstract
- Prostatacancer är den vanligaste cancersjukdomen och den vanligaste cancerrelaterade dödsorsaken bland män i Sverige. Screening för prostataspecifikt antigen (PSA) minskade dödligheten i prostatacancer med 20 procent i en stor randomiserad studie. En utvärdering av PSA-test med sannolikhetskvot (likelihood ratio) visade att det inte uppfyller kriterierna för ett screeningtest. Män ska ha information om PSA-testets för- och nackdelar innan testet utförs. En broschyr med sådan information finns tillgänglig på .
|
|
| 8. |
- Jakszyn, Paula G, et al.
(author)
-
Nitrosamines and Heme Iron and Risk of Prostate Cancer in the European Prospective Investigation into Cancer and Nutrition.
- 2012
-
In: Cancer Epidemiology, Biomarkers and Prevention. - 1055-9965 .- 1538-7755. ; 21:3, s. 547-551
-
Journal article (peer-reviewed)abstract
- BACKGROUND: The evidence about nitrosamines and heme iron intake and cancer risk is limited, despite the biologic plausibility of the hypothesis that these factors might increase cancer risk. We investigated the association between dietary nitrosamines and heme iron and the risk of prostate cancer among participants of European Prospective Investigation into Cancer and Nutrition (EPIC).METHODS: Data on food consumption and complete follow-up for cancer occurrence was available for 139,005 men, recruited in 8 European countries. Estimates of HRs were obtained by proportional hazard models, stratified by age at recruitment, and study center, and adjusted for total energy intake, smoking status, marital status, dairy products, educational level, and body mass index.RESULTS: After a mean follow-up of 10 years, 4,606 participants were diagnosed with first incident prostate cancer. There was no overall association between prostate cancer risk and nitrosamines exposure (preformed and endogenous) or heme iron intake (HR for a doubling of intake: 1.00; 95% CI: 0.98-1.03 for N-Nitrosodimethlyamine, 0.95; 95% CI: 0.88-1.03 for endogenous Nitrosocompounds, and 1.00; 95 CI: 0.97-1.03 for heme iron).Conclusions and Impact: Our findings do not support an effect of nitrosamines (endogenous and exogenous) and heme iron intake on prostate cancer risk.
|
|
| 9. |
- Johansson, Mattias, et al.
(author)
-
Circulating concentrations of folate and vitamin B12 in relation to prostate cancer risk : results from the European prospective investigation into cancer and nutrition study
- 2008
-
In: Cancer Epidemiol Biomarkers Prev. - 1055-9965. ; 17:2, s. 279-285
-
Journal article (peer-reviewed)abstract
- Background: Determinants of one-carbon metabolism, such as folate and vitamin B12, have been implicated in cancer development. Previous studies have not provided conclusive evidence for the importance of circulating concentrations of folate and vitamin B12 in prostate cancer etiology. The aim of the present study was to investigate the relationship between prostate cancer risk and circulating concentrations of folate and vitamin B12 in a large prospective cohort. Methods: We analyzed circulating concentrations of folate and vitamin B12 in 869 cases and 1,174 controls, individually matched on center, age, and date of recruitment, nested within the European Prospective Investigation into Cancer and Nutrition cohort. Relative risks (RR) for prostate cancer were estimated using conditional logistic regression models. Results: Overall, no significant associations were observed for circulating concentrations of folate (Ptrend = 0.62) or vitamin B12 (Ptrend = 0.21) with prostate cancer risk. RRs for a doubling in folate and vitamin B12 concentrations were 1.03 [95% confidence interval (95% CI), 0.92-1.16] and 1.12 (95% CI, 0.94-1.35), respectively. In the subgroup of cases diagnosed with advanced stage prostate cancer, elevated concentrations of vitamin B12 were associated with increased risk (RR for a doubling in concentration, 1.69; 95% CI, 1.05-2.72, Ptrend = 0.03). No other subgroup analyses resulted in a statistically significant association. Conclusion: This study does not provide strong support for an association between prostate cancer risk and circulating concentrations of folate or vitamin B12. Elevated concentrations of vitamin B12 may be associated with an increased risk for advanced stage prostate cancer, but this association requires examination in other large prospective studies. (Cancer Epidemiol Biomarkers Prev 2007;17(2):279–85)
|
|
| 10. |
- Johansson, Mattias, et al.
(author)
-
Combining 33 genetic variants with prostate-specific antigen for prediction of prostate cancer : longitudinal study
- 2012
-
In: International Journal of Cancer. - : Wiley. - 0020-7136 .- 1097-0215. ; 130:1, s. 129-137
-
Journal article (peer-reviewed)abstract
- The aim of this study was to investigate if a genetic risk score including 33 common genetic variants improves prediction of prostate cancer when added to measures of prostate-specific antigen (PSA). We conducted a case-control study nested within the Northern Sweden Health and Disease Cohort (NSHDC), a prospective cohort in northern Sweden. A total of 520 cases and 988 controls matched for age, and date of blood draw were identified by linkage between the regional cancer register and the NSHDC. Receiver operating characteristic curves with area under curve (AUC) estimates were used as measures of prostate cancer prediction. The AUC for the genetic risk score was 64.3% [95% confidence interval (CI) = 61.4-67.2], and the AUC for total PSA and the ratio of free to total PSA was 86.2% (95% CI = 84.4-88.1). A model including the genetic risk score, total PSA and the ratio of free to total PSA increased the AUC to 87.2% (95% CI = 85.4-89.0, p difference = 0.002). The addition of a genetic risk score to PSA resulted in a marginal improvement in prostate cancer prediction that would not seem useful for clinical risk assessment.
|
|
