***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
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    Input: Purpose A few recent epidemiological observations suggest that anticoagulant medications may protect against  prostate cancer development . Most studies have been small or subjected to method ological issues , including potential confounding . We provide here new evidence on this association in the context of a population -based case – control study of prostate cancer conducted in Montreal , Canada . Methods Cases were 1,588 men with incident prostate cancer , aged ≤75 years , diagnosed across French hospitals in the Montreal area between 2005 and 2009 . Concurrently , 1,618 population controls from the same residential area and age distribution ( ±5 years ) were r and omly selected from the electoral list of French-speaking men .  In-person interviews elicited information on socio-demographic , lifestyle and environmental factors , along with a detailed medical history . Unconditional logistic regression was used to assess the association between lifetime use  of anticoagulants  and prostate cancer risk . Results 102 subjects ( 2.6 % of cases and 3.7 % of controls ) reported a history  of oral anticoagulant therapy . After controlling for age , ancestry , education , family history of prostate cancer , prostate cancer screening frequency , diabetes , body mass index and statin use , ever use of oral anticoagulants showed a weak inverse , non-statistically significant association with prostate cancer ( odds ratio 0.76 , 95 % confidence interval 0.50–1.16 ) . Similar results were observed in analyses considering duration of use or indication for use , restricted to subjects recently screened or stratified by cancer aggressiveness . Conclusions Our findings provide weak support for a protective effect of oral anticoagulant therapy against prostate cancer . Further confirmation is required , especially in light of potential bleeding complications associated with anticoagulants BACKGROUND The influence of the duration of anticoagulant therapy after venous thromboembolism ( VTE ) on the long-term morbidity and mortality is unclear . AIM To investigate the long-term sequelae of VTE in patients r and omized to different duration of secondary prophylaxis . METHODS In a multicenter trial comparing secondary prophylaxis with vitamin K antagonists for 6 weeks or 6 months , we extended the originally planned 2 years follow-up to 10 years . The patients had annual visits and at the last visit clinical assessment of the post-thrombotic syndrome ( PTS ) was performed . Recurrent thromboembolism was adjudicated by a radiologist , blinded to treatment allocation . Causes of death were obtained from the Swedish Death Registry . RESULTS Of the 897 patients r and omized , 545 could be evaluated at the 10 years follow-up . The probability of developing severe PTS was 6 % and any sign of PTS was seen in 56.3 % of the evaluated patients . In multivariate analysis , old age and signs of impaired circulation at discharge from the hospital were independent risk factors at baseline for development of PTS after 10 years . Recurrent thromboembolism occurred in 29.1 % of the patients with a higher rate among males , older patients , those with permanent triggering risk factor - especially with venous insufficiency at baseline - signs of impaired venous circulation at discharge , proximal deep vein thrombosis , or pulmonary embolism . Death occurred in 28.5 % , which was a higher mortality than expected with a st and ardized incidence ratio ( SIR ) of 1.43 ( 95 % CI 1.28 - 1.58 ) , mainly because of a higher mortality than expected from cancer ( SIR 1.83 ; 95 % CI 1.44 - 2.23 ) or from myocardial infa rct ion or stroke ( SIR 1.28 ; 95 % CI 1.00 - 1.56 ) . The duration of anticoagulation  did not have a statistically significant effect on any of the long-term outcomes . CONCLUSION The morbidity and mortality during 10 years after the first episode of VTE is high and not reduced by extension of secondary prophylaxis from 6 weeks to 6 months . A strategy to reduce recurrence of VTE as well as mortality from arterial disease is needed Purpose Recent evidence suggests that warfarin use may be associated with a reduced risk of prostate cancer .  We aim ed to determine whether exposure to warfarin is also associated with a reduced risk of prostate cancer death . Methods A nested case – control study was conducted within a population -based cohort of 10,012 men aged ≥50 years with newly diagnosed prostate cancer between 1985 and 2002 and with no history of cancer since 1970 using the linked records of Saskatchewan Health and Saskatchewan Cancer Agency registry . We identified 2,309 cases who died of prostate cancer during follow-up . For each case , one control alive at the time of the case ’s death and matched for length of follow-up ( ±6 months ) was r and omly selected . Prescription counts were used to define warfarin exposure . Multivariate conditional logistic regression analysis was used to calculate the adjusted incidence rates of prostate cancer death in relation to warfarin use while adjusting for confounding by age , year of prostate cancer diagnosis , clinical stage and grade of cancer at diagnosis , Chronic Disease Score , and use of warfarin before diagnosis . Results Ever use of warfarin following a diagnosis of prostate cancer was associated with an adjusted rate ratio of 1.44 ( 95 % confidence interval ( CI ) 1.33–1.84 ) for prostate cancer death . The adjusted rate ratio with one-year use of warfarin was 1.77 ( 95 % CI 1.25–2.50 ) compared to never use . The unadjusted rate ratio with five-year use of warfarin was 0.64 ( 95 % CI 0.40–1.00 ) and remained unchanged in the adjusted analysis ( 0.65 , 95 % CI 0.37–1.13 ) , although no longer statistically significant . Conclusion Our study does not provide conclusive evidence for a protective effect of long-term warfarin  on prostate cancer-specific mortality . Moreover , short-term warfarin use may be associated with an increased risk of prostate cancer death BACKGROUND The length of time after an episode of venous thromboembolism during which the risk of newly diagnosed cancer is increased is not known , and whether vitamin K antagonists have an antineoplastic effect is controversial . METHODS In a prospect i ve , r and omized study of the duration of oral anticoagulation ( six weeks or six months ) after a first episode of venous thromboembolism , patients were question ed annually about any newly diagnosed cancer . After a mean follow-up of 8.1 years , we used the Swedish Cancer Registry to identify all diagnoses of cancer and causes of death in the study population . The observed numbers of cases of cancer were compared with expected numbers based on national incidence rates , and the st and ardized incidence ratios were calculated . RESULTS A first cancer was diagnosed in 111 of 854 patients ( 13.0 percent ) during follow-up . The st and ardized incidence ratio for newly diagnosed cancer was 3.4 ( 95 percent confidence interval , 2.2 to 4.6 ) during the first year after the thromboembolic event and remained between 1.3 and 2.2 for the following five years . Cancer was diagnosed in 66 of 419 patients ( 15.8 percent ) who were treated for six weeks with oral anticoagulants , as compared with 45 of 435 patients ( 10.3 percent ) who were treated for six months ( odds ratio , 1.6 ; 95 percent confidence interval , 1.1 to 2.4 ) . The difference was mainly due to the occurrence of new urogenital cancers , of which there were 28 cases in the six-week group ( 6.7 percent ) and 12 cases in the six-month group ( 2.8 percent ) ( odds ratio , 2.5 ; 95 percent confidence interval , 1.3 to 5.0 ) . The difference in the incidence of cancer between the treatment groups became evident only after two years of follow-up , and it remained significant after adjustment for sex , age , and whether the thromboembolism was idiopathic or nonidiopathic . Older age at the time of the venous thrombosis and an idiopathic thromboembolism were also independent risk factors for a diagnosis of cancer . No difference in the incidence of cancer-related deaths was detected . CONCLUSIONS The risk of newly diagnosed cancer after a first episode of venous thromboembolism is elevated during at least the following two years . Subsequently , the risk seems to be lower among patients treated with oral anticoagulants for six months than among those treated for six weeks BACKGROUND Indirect evidence suggests that prolonged treatment with warfarin might be associated with a decreased incidence of urogenital cancer .  We aim ed to assess this association in a large population -based study . METHODS Beneficiaries of Saskatchewan Health who were eligible for prescription drug benefits and aged 50 years or over with no history of cancer since 1967 were enrolled into a nested , matched case-control study . 19 412 new cases of urogenital cancer diagnosed between Jan 1 , 1981 , and Dec 31 , 2002 , were identified by use of information from the Saskatchewan Cancer Agency registry . For each case , six controls , totalling 116 470 , who were matched for age , sex , and time of diagnosis were selected r and omly . Conditional logistic regression analysis was used to calculate adjusted incidence rates of urogenital cancer in relation to warfarin use . FINDINGS Compared with men who never used warfarin , men with 4 years of warfarin use had an adjusted incidence rate of 0.80 ( 95 % CI [ 0.65 - 0.99 ] ) . For warfarin use 76 - 100 % of the time , the adjusted rate ratios were 0.80 ( 0.66 - 0.96 ) during year 2 preceding diagnosis of prostate cancer , 0.76 ( 0.62 - 0.94 ) during year 3 , and 0.67 ( 0.53 - 0.86 ) during year 4 . No significant association was found between warfarin and risk of other urogenital cancers . INTERPRETATION Our results suggest that warfarin has an antitumour effect that is specific to prostate cancer . Further investigation , with more complete assessment of confounders and that addresses the effect of warfarin on mortality of prostate cancer , is warranted IMPORTANCE A substantial proportion of patients with atrial fibrillation ( AF ) die of noncardiovascular causes , and recent studies suggest a link between AF and cancer . OBJECTIVE To evaluate the associations between AF and cancer in a large , long-term prospect i ve cohort study . DESIGN , SETTING , AND PARTICIPANTS In this cohort study , a total of 34 691 women 45 years or older and free of AF , cardiovascular disease , and cancer at baseline were prospect ively followed up between 1993 and 2013 , for incident AF and malignant cancer within the Women 's Health Study , a r and omized clinical trial of aspirin and vitamin E for the prevention of cardiovascular disease and cancer . Cox proportional hazards models using time-up date d covariates were constructed to assess the association of new-onset AF with subsequent cancer and to adjust for potential confounders . Data analysis was performed from December 2014 to May 2015 . EXPOSURE New-onset AF . MAIN OUTCOMES AND MEASURES Incident malignant cancer confirmed by an end point committee . RESULTS During a median follow-up of 19.1 years of 34 691 study participants ( interquartile range [ IQR ] , 17.6 - 19.7 years ) , new-onset AF and malignant cancer were confirmed among 1467 ( 4.2 % ) and 5130 ( 14.8 % ) participants , respectively . Median age at baseline among participants with new-onset AF and new-onset cancer during follow-up was 58 years ( IQR , 52 - 64 years ) and 55 years ( IQR , 50 - 61 years ) , respectively . Atrial fibrillation was a significant risk factor for incident cancer in age-adjusted ( hazard ratio [ HR ] , 1.58 ; 95 % CI , 1.34 - 1.87 ; P < .001 ) and multivariable-adjusted ( HR , 1.48 ; 95 % CI , 1.25 - 1.75 ; P < .001 ) models . The relative risk of cancer was highest in the first 3 months after new-onset AF ( HR , 3.54 ; 95 % CI , 2.05 - 6.10 ; P < .001 ) but remained significant beyond 1 year after new-onset AF ( adjusted HR , 1.42 ; 95 % CI , 1.18 - 1.71 ; P < .001 ) , and a trend toward an increased cancer mortality was observed ( adjusted HR , 1.32 ; 95 % CI , 0.98 - 1.79 ; P = .07 ) . In contrast , among women with new-onset cancer , the relative risk of AF was increased only within the first 3 months ( HR , 4.67 ; 95 % CI , 2.85 - 7.64 ; P < .001 ) but not thereafter ( HR , 1.15 ; 95 % CI , 0.95 - 1.39 ; P = .15 ) . CONCLUSIONS AND RELEVANCE In this large , initially healthy cohort , women with new-onset AF had an elevated cancer 
    Output:
    
Conclusions : The use of long-term VKAs , for any indication , is associated with lower cancer incidence .