869 resultados para Cox regression
Resumo:
Increased number of circulating monocytes at presentation has been recently associated with shorter survival in Hodgkin lymphoma, follicular lymphoma and diffuse large B cell lymphoma. This study aimed to assess the prognostic impact of the absolute monocyte count (AMC) at diagnosis in mantle cell lymphoma (MCL). From the series of MCL cases recorded on the databases of the Oncology Institute of Southern Switzerland in Bellinzona (Switzerland) and the Division of Haematology of the Amedeo Avogadro University of Eastern Piedmont in Novara (Italy), the AMC at diagnosis was available in 97 cases. Cox regression was used for both univariate and multivariate analysis. With a median follow up of 7 years, the 5-year overall survival (OS) was 29% for patients with AMC >500/ul and 62% for patients with AMC
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Background:We conducted the first study to investigate post-diagnostic oral bisphosphonates use and colorectal cancer-specific mortality.
Methods:Colorectal cancer patients were identified from the National Cancer Data Repository (1998–2007) and linked to the UK Clinical Practice Research Datalink, providing prescription records, and Office of National Statistics mortality data. Time-dependent Cox regression models investigated colorectal cancer-specific mortality in post-diagnostic bisphosphonate users.
Results:Overall, in 4791 colorectal cancer patients, there was no evidence of an association between bisphosphonate use and colorectal cancer-specific mortality (adjusted hazard ratio=1.11; 95% confidence interval 0.80, 1.54) or with drug frequency or type.
Conclusions:In this novel population-based cohort study, post-diagnostic bisphosphonate use was not associated with longer rates of colorectal cancer survival.
Resumo:
Digoxin has been shown to have an estrogenic effect and is associated with increased risk of gynecomastia and estrogen-sensitive cancers such as breast and uterus cancer. These findings, particularly recent observations of increased breast cancer risk, raise questions about the safety of digoxin use in breast cancer patients. Therefore, we investigated whether digoxin use after breast cancer diagnosis increased the risk of breast cancer-specific mortality in breast cancer patients. A cohort of 17,842 breast cancer patients newly diagnosed from 1998 to 2009 was identified from English cancer registries (from the National Cancer Data Repository). This cohort was linked to the UK Clinical Practice Research Datalink (to provide digoxin and other prescription records) and to the Office of National Statistics mortality data (to identify breast cancer-specific deaths). Using time-dependent Cox regression models, unadjusted and adjusted hazard ratios (HR) and 95 % confidence intervals (CIs) were calculated for the association between post-diagnostic exposure to digoxin and breast cancer-specific and all-cause mortality. In 17,842 breast cancer patients, there were 2219 breast cancer-specific deaths. Digoxin users appeared to have increased breast cancer-specific mortality compared with non-users (HR 1.73; 95 % CI 1.39–2.15) but this association was entirely attenuated after adjustment for potential confounders (adjusted HR 0.91; 95 % CI 0.72–1.14). In this large population-based breast cancer cohort study, there was little evidence of an increase in breast cancer-specific mortality with digoxin use after diagnosis. These results provide some reassurance that digoxin use is safe in breast cancer patients.
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PURPOSE: To investigate whether statins used after colorectal cancer diagnosis reduce the risk of colorectal cancer-specific mortality in a cohort of patients with colorectal cancer.
PATIENTS AND METHODS: A cohort of 7,657 patients with newly diagnosed stage I to III colorectal cancer were identified from 1998 to 2009 from the National Cancer Data Repository (comprising English cancer registry data). This cohort was linked to the United Kingdom Clinical Practice Research Datalink, which provided prescription records, and to mortality data from the Office of National Statistics (up to 2012) to identify 1,647 colorectal cancer-specific deaths. Time-dependent Cox regression models were used to calculate hazard ratios (HR) for cancer-specific mortality and 95% CIs by postdiagnostic statin use and to adjust these HRs for potential confounders.
RESULTS: Overall, statin use after a diagnosis of colorectal cancer was associated with reduced colorectal cancer-specific mortality (fully adjusted HR, 0.71; 95% CI, 0.61 to 0.84). A dose-response association was apparent; for example, a more marked reduction was apparent in colorectal cancer patients using statins for more than 1 year (adjusted HR, 0.64; 95% CI, 0.53 to 0.79). A reduction in all-cause mortality was also apparent in statin users after colorectal cancer diagnosis (fully adjusted HR, 0.75; 95% CI, 0.66 to 0.84).
CONCLUSION: In this large population-based cohort, statin use after diagnosis of colorectal cancer was associated with longer rates of survival.
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OBJECTIVE: To examine a panel of 28 biomarkers for prediction of cardiovascular disease (CVD) and non-CVD mortality in a population-based cohort of men.
METHODS: Starting in 1979, middle-aged men in Caerphilly underwent detailed medical examination. Subsequently 2171 men were re-examined during 1989-1993, and fasting blood samples obtained from 1911 men (88%). Fibrinogen, viscosity and white cell count (WCC), routine biochemistry tests and lipids were analysed using fresh samples. Stored aliquots were later analysed for novel biomarkers. Statistical analysis of CVD and non-CVD mortality follow-up used competing risk Cox regression models with biomarkers in thirds tested at the 1% significance level after covariate adjustment.
RESULTS: During an average of 15.4years follow-up, troponin (subhazard ratio per third 1.71, 95% CI 1.46-1.99) and B-natriuretic peptide (BNP) (subhazard ratio per third 1.54, 95% CI 1.34-1.78) showed strong trends with CVD death but not with non-CVD death. WCC and fibrinogen showed similar weaker findings. Plasma viscosity, growth differentiation factor 15 (GDF-15) and interleukin-6 (IL-6) were associated positively with both CVD death and non-CVD death while total cholesterol was associated positively with CVD death but negatively with non-CVD death. C-reactive protein (C-RP), alkaline phosphatase, gamma-glutamyltransferase (GGT), retinol binding protein 4 (RBP-4) and vitamin B6 were significantly associated only with non-CVD death, the last two negatively. Troponin, BNP and IL-6 showed evidence of diminishing associations with CVD mortality through follow-up.
CONCLUSION: Biomarkers for cardiac necrosis were strong, specific predictors of CVD mortality while many inflammatory markers were equally predictive of non-CVD mortality.
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Preclinical evidence suggests that metformin could delay cancer progression. Previous epidemiological studies however have been limited by small sample sizes and certain time-related biases. This study aimed to investigate whether colorectal cancer patients with type 2 diabetes who were exposed to metformin had reduced cancer-specific mortality. We conducted a retrospective cohort study of 1,197 colorectal cancer patients newly diagnosed from 1998 to 2009 (identified from English cancer registries) with type 2 diabetes (based upon Clinical Practice Research Datalink, CPRD, prescription and diagnosis records). In this cohort 382 colorectal cancer-specific deaths occurred up to 2012 from the Office of National Statistics (ONS) mortality data. Metformin use was identified from CPRD prescription records. Using time-dependent Cox regression models, unadjusted and adjusted hazard ratios (HR) and 95% CIs were calculated for the association between post-diagnostic exposure to metformin and colorectal cancer-specific mortality. Overall, there was no evidence of an association between metformin use and cancer-specific death before or after adjustment for potential confounders (adjusted HR 1.06, 95% CI 0.80, 1.40). In addition, after adjustment for confounders, there was also no evidence of associations between other diabetic medications and cancer-specific mortality including sulfonylureas (HR 1.14, 95% CI 0.86, 1.51), insulin use (HR 1.35, 95% CI 0.95, 1.93) or other anti-diabetic medications including thiazolidinediones (HR 0.73, 95% CI 0.46, 1.14). Similar associations were observed by duration of use and for all-cause mortality. This population-based study, the largest to date, does not support a protective association between metformin and survival in colorectal cancer patients.
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BACKGROUND: Lapatinib plus capecitabine emerged as an efficacious therapy in metastatic breast cancer (mBC). We aimed to identify germline single-nucleotide polymorphisms (SNPs) in genes involved in capecitabine catabolism and human epidermal receptor signaling that were associated with clinical outcome to assist in selecting patients likely to benefit from this combination.
PATIENTS AND METHODS: DNA was extracted from 240 of 399 patients enrolled in EGF100151 clinical trial (NCT00078572; clinicaltrials.gov) and SNPs were successfully evaluated in 234 patients. The associations between SNPs and clinical outcome were analyzed using Fisher's exact test, Kaplan-Meier curves, log-rank tests, likelihood ratio test within logistic or Cox regression model, as appropriate.
RESULTS: There were significant interactions between CCND1 A870G and clinical outcome. Patients carrying the A-allele were more likely to benefit from lapatinib plus capecitabine versus capecitabine when compared with patients harboring G/G (P = 0.022, 0.024 and 0.04, respectively). In patients with the A-allele, the response rate (RR) was significantly higher with lapatinib plus capecitabine (35%) compared with capecitabine (11%; P = 0.001) but not between treatments in patients with G/G (RR = 24% and 32%, respectively; P = 0.85). Time to tumor progression (TTP) was longer in patients with the A-allele treated with lapatinib plus capecitabine compared with capecitabine (median TTP = 7.9 and 3.4 months; P < 0.001), but not in patients with G/G (median TTP = 6.1 and 6.6 months; P = 0.92).
CONCLUSION: Our findings suggest that CCND1A870G may be useful in predicting clinical outcome in HER2-positive mBC patients treated with lapatinib plus capecitabine.
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PURPOSE: There is substantial germline genetic variability within angiogenesis pathway genes, thereby causing interindividual differences in angiogenic capacity and resistance to antiangiogenesis therapy. We investigated germline polymorphisms in genes involved in VEGF-dependent and -independent angiogenesis pathways to predict clinical outcome and tumor response in metastatic colorectal cancer (mCRC) patients treated with bevacizumab and oxaliplatin-based chemotherapy.
EXPERIMENTAL DESIGN: A total of 132 patients treated with first-line bevacizumab and FOLFOX or XELOX were included in this study. Genomic DNA was isolated from whole-blood samples by PCR-RFLP or direct DNA sequencing. The endpoints of the study were progression-free survival (PFS), overall survival (OS), and response rate (RR).
RESULTS: The minor alleles of EGF rs444903 A>G and IGF-1 rs6220 A>G were associated with increased OS and remained significant in multivariate Cox regression analysis (HR: 0.52; 95% CI: 0.31-0.87; adjusted P = 0.012 and HR: 0.60; 95% CI: 0.36-0.99; adjusted P = 0.046, respectively). The minor allele of HIF1α rs11549465 C>T was significantly associated with increased PFS but lost its significance in multivariate analysis. CXCR1 rs2234671 G>C, CXCR2 rs2230054 T>C, EGFR rs2227983 G>A, and VEGFR-2 rs2305948 C>T predicted tumor response, with CXCR1 rs2234671 G>C remaining significant in multiple testing (P(act) = 0.003).
CONCLUSION: In this study, we identified common germline variants in VEGF-dependent and -independent angiogenesis genes predicting clinical outcome and tumor response in patients with mCRC receiving first-line bevacizumab and oxaliplatin-based chemotherapy.
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Background
Preclinical evidence suggests that aspirin may inhibit lung cancer progression. In a large cohort of lung cancer patients, we investigated whether low-dose aspirin use was associated with a reduction in the risk of lung cancer-specific mortality.
Methods
We identified lung cancer patients from English cancer registries diagnosed between 1998 to 2009 from the National Cancer Data Repository. Medication usage was obtained from linkages to the UK Clinical Practice Research Datalink and lung cancer-specific deaths were identified from Office of National Statistics mortality data. Hazard ratios (HR) and 95 % confidence intervals (CI) for the association between low-dose aspirin use (before and after diagnosis) and risk of lung cancer-specific mortality were calculated using Cox regression models.
Results
A total of 14,735 lung cancer patients were identified during the study period. In analysis of 3,635 lung cancer patients, there was no suggestion of an association between low-dose aspirin use after diagnosis and cancer-specific mortality (adjusted HR = 0.96, 95 % CI: 0.85, 1.09). Similarly, no association was evident for low-dose aspirin use before diagnosis and cancer-specific mortality (adjusted HR = 1.00, 95 % CI: 0.95, 1.05). Associations were comparable by duration of use and for all-cause mortality.
Conclusion
Overall, we found little evidence of a protective association between low-dose aspirin use and cancer-specific mortality in a large population-based lung cancer cohort.
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BACKGROUND: The androgen receptor (AR) is a major drug target in prostate cancer (PCa). We profiled the AR-regulated kinome to identify clinically relevant and druggable effectors of AR signaling.
METHODS: Using genome-wide approaches, we interrogated all AR regulated kinases. Among these, choline kinase alpha (CHKA) expression was evaluated in benign (n = 195), prostatic intraepithelial neoplasia (PIN) (n = 153) and prostate cancer (PCa) lesions (n = 359). We interrogated how CHKA regulates AR signaling using biochemical assays and investigated androgen regulation of CHKA expression in men with PCa, both untreated (n = 20) and treated with an androgen biosynthesis inhibitor degarelix (n = 27). We studied the effect of CHKA inhibition on the PCa transcriptome using RNA sequencing and tested the effect of CHKA inhibition on cell growth, clonogenic survival and invasion. Tumor xenografts (n = 6 per group) were generated in mice using genetically engineered prostate cancer cells with inducible CHKA knockdown. Data were analyzed with χ(2) tests, Cox regression analysis, and Kaplan-Meier methods. All statistical tests were two-sided.
RESULTS: CHKA expression was shown to be androgen regulated in cell lines, xenografts, and human tissue (log fold change from 6.75 to 6.59, P = .002) and was positively associated with tumor stage. CHKA binds directly to the ligand-binding domain (LBD) of AR, enhancing its stability. As such, CHKA is the first kinase identified as an AR chaperone. Inhibition of CHKA repressed the AR transcriptional program including pathways enriched for regulation of protein folding, decreased AR protein levels, and inhibited the growth of PCa cell lines, human PCa explants, and tumor xenografts.
CONCLUSIONS: CHKA can act as an AR chaperone, providing, to our knowledge, the first evidence for kinases as molecular chaperones, making CHKA both a marker of tumor progression and a potential therapeutic target for PCa.
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BACKGROUND: Smoking is the most important individual risk factor for many cancer sites but its association with breast and prostate cancer is not entirely clear. Rate advancement periods (RAPs) may enhance communication of smoking related risk to the general population. Thus, we estimated RAPs for the association of smoking exposure (smoking status, time since smoking cessation, smoking intensity, and duration) with total and site-specific (lung, breast, colorectal, prostate, gastric, head and neck, and pancreatic) cancer incidence and mortality.
METHODS: This is a meta-analysis of 19 population-based prospective cohort studies with individual participant data for 897,021 European and American adults. For each cohort we calculated hazard ratios (HRs) for the association of smoking exposure with cancer outcomes using Cox regression adjusted for a common set of the most important potential confounding variables. RAPs (in years) were calculated as the ratio of the logarithms of the HRs for a given smoking exposure variable and age. Meta-analyses were employed to summarize cohort-specific HRs and RAPs.
RESULTS: Overall, 140,205 subjects had a first incident cancer, and 53,164 died from cancer, during an average follow-up of 12 years. Current smoking advanced the overall risk of developing and dying from cancer by eight and ten years, respectively, compared with never smokers. The greatest advancements in cancer risk and mortality were seen for lung cancer and the least for breast cancer. Smoking cessation was statistically significantly associated with delays in the risk of cancer development and mortality compared with continued smoking.
CONCLUSIONS: This investigation shows that smoking, even among older adults, considerably advances, and cessation delays, the risk of developing and dying from cancer. These findings may be helpful in more effectively communicating the harmful effects of smoking and the beneficial effect of smoking cessation.
Resumo:
PURPOSE: Concerns were raised about the safety of antiplatelet thienopyridine derivatives after a randomized control trial reported increased risks of cancer and cancer deaths in prasugrel users. We investigate whether clopidogrel, a widely used thienopyridine derivative, was associated with increased risk of cancer-specific or all-cause mortality in cancer patients.
METHODS: Colorectal, breast and prostate cancer patients, newly diagnosed from 1998 to 2009, were identified from the National Cancer Data Repository. Cohorts were linked to the UK Clinical Practice Research Datalink, providing prescription records, and to the Office of National Statistics mortality data (up to 2012). Unadjusted and adjusted hazard ratios (HRs) for cancer-specific and all-cause mortality in post-diagnostic clopidogrel users were calculated using time-dependent Cox regression models.
RESULTS: The analysis included 10 359 colorectal, 17 889 breast and 13 155 prostate cancer patients. There was no evidence of an increase in cancer-specific mortality in clopidogrel users with colorectal (HR = 0.98 95% confidence interval (CI) 0.77, 1.24) or prostate cancer (HR = 1.03 95%CI 0.82, 1.28). There was limited evidence of an increase in breast cancer patients (HR = 1.22 95%CI 0.90, 1.65); however, this was attenuated when removing prescriptions in the year prior to death.
CONCLUSIONS: This novel study of large population-based cohorts of colorectal, breast and prostate cancer patients found no evidence of an increased risk of cancer-specific mortality among colorectal, breast and prostate cancer patients using clopidogrel.
Resumo:
BACKGROUND: Preclinical studies have shown that statins, particularly simvastatin, can prevent growth in breast cancer cell lines and animal models. We investigated whether statins used after breast cancer diagnosis reduced the risk of breast cancer-specific, or all-cause, mortality in a large cohort of breast cancer patients.
METHODS: A cohort of 17,880 breast cancer patients, newly diagnosed between 1998 and 2009, was identified from English cancer registries (from the National Cancer Data Repository). This cohort was linked to the UK Clinical Practice Research Datalink, providing prescription records, and to the Office of National Statistics mortality data (up to 2013), identifying 3694 deaths, including 1469 deaths attributable to breast cancer. Unadjusted and adjusted hazard ratios (HRs) for breast cancer-specific, and all-cause, mortality in statin users after breast cancer diagnosis were calculated using time-dependent Cox regression models. Sensitivity analyses were conducted using multiple imputation methods, propensity score methods and a case-control approach.
RESULTS: There was some evidence that statin use after a diagnosis of breast cancer had reduced mortality due to breast cancer and all causes (fully adjusted HR = 0.84 [95% confidence interval = 0.68-1.04] and 0.84 [0.72-0.97], respectively). These associations were more marked for simvastatin 0.79 (0.63-1.00) and 0.81 (0.70-0.95), respectively.
CONCLUSIONS: In this large population-based breast cancer cohort, there was some evidence of reduced mortality in statin users after breast cancer diagnosis. However, these associations were weak in magnitude and were attenuated in some sensitivity analyses.
Resumo:
BACKGROUND:
Digoxin has been shown to affect a number of pathways that are of relevance to cancer, and its use has been associated with increased risks of breast and uterus cancer and, more recently, a 40% increase in colorectal cancer risk. These findings raise questions about the safety of digoxin use in colorectal cancer patients, and, therefore, we investigated whether digoxin use after colorectal cancer diagnosis increased the risk of colorectal cancer-specific mortality.
METHODS:
A cohort of 10,357 colorectal cancer patients newly diagnosed from 1998 to 2009 was identified from English cancer registries and linked to the UK Clinical Practice Research Datalink (to provide digoxin and other prescription records) and to the Office of National Statistics mortality data (to identify 2,724 colorectal cancer-specific deaths). Using time-dependent Cox regression models, unadjusted and adjusted HRs and 95% confidence intervals (CI) were calculated for the association between postdiagnostic exposure to digoxin and colorectal cancer-specific mortality.
RESULTS:
Overall, 682 (6%) colorectal cancer patients used digoxin after diagnosis. Digoxin use was associated with a small increase in colorectal cancer-specific mortality before adjustment (HR, 1.25; 95% CI, 1.07-1.46), but after adjustment for confounders, the association was attenuated (adjusted HR, 1.10; 95% CI, 0.91-1.34) and there was no evidence of a dose response.
CONCLUSIONS:
In this large population-based colorectal cancer cohort, there was little evidence of an increase in colorectal cancer-specific mortality with digoxin use after diagnosis.
IMPACT:
These results provide some reassurance that digoxin use is safe in colorectal cancer patients.
Resumo:
Tese de mestrado em Bioestatística, apresentada à Universidade de Lisboa, através da Faculdade de Ciências, 2013
