Does warfarin therapy influence the risk of bladder cancer?

Summary

There has been growing interest in studying the biological effects of certain drugs and their potential to reduce the risk of various cancers. One study reported a decrease in the incidence of urogenital cancers in a trial with patients who received warfarin for treatment of venous thromboembolism, but a limitation to this study of urogenital cancers was the very small number of bladder cancer cases that developed following warfarin therapy. The objective of the present study is to measure the association between warfarin use and bladder cancer. A total of 330 cases with bladder cancer were identified at the James A. Haley Veterans’ Administration (VA) Hospital in Tampa, Florida, using a combination of computerized pathology records and inpatient and outpatient diagnoses. Controls were randomly selected from the VA computerized administrative database and 1293 controls were included for analysis. Unconditional logistic regression analysis was performed to assess the risk of bladder cancer after adjusting for age, gender, and cigarette smoking. Among warfarin users, although there was a 27% elevation in risk, it did not differ significantly from nonusers (OR = 1.27, 95% CI = 0.85, 1.89). No durationresponse relationship was observed between anticoagulant use and risk of bladder cancer. The results suggest that warfarin does not protect against bladder cancer, at least in male smokers, the highest risk population for bladder cancer.

Keywords

Bladder cancer - case-control study - cigarette smoking - warfarin

• References

• 1 Boring CC, Squires TS, Tong T. et al. Cancer statistics 1994; CA Cancer. J Clin 1994; 44 (01) 7-26.
• 2 Mason TJ, McKay F, Hoover R. et al. Atlas of Cancer Mortality for US Counties: 1950-1969. DHEW Publ. No. (NIH). 75-780 Washington, DC: US Govt Printing Office; 1975
• 3 Hartge P, Silverman D, Hoover R. et al. Changing cigarette habits and bladder cancer risk: a case-control study. J Natl Cancer Inst 1987; 78: 1119-25.
• 4 Castelao JE, Yuan J-M, Gago-Dominguez M. et al. Non-steroidal anti-inflammatory drugs and bladder cancer prevention. Br J Cancer 2000; 82: 1364-9.
• 5 Schulman S, Lindmarker P. Incidence of cancer after prophylaxis against venous thromboembolism with warfarin. N Engl J Med 2000; 342: 1953-8.
• 6 Zacharski LR, Henderson WG, Rickles FR. et al. Effect of warfarin on survival in small cell carcinoma of the lung. Veterans Administration Study No. 75. JAMA 1981; 245: 831-5.
• 7 Zacharski LR, Henderson WG, Rickles FR. et al. Effect of warfarin anticoagulation on survival in carcinoma of the lung, colon, head and neck, and prostate: final report of VA Cooperative Study #75. Cancer 1984; 53: 2046-52.
• 8 Taniguchi T, Kakkar AK, Tuddenham EG. et al. Enhanced expression of urokinase receptor induced through the tissue factor-factor VIIa pathway in human pancreatic cancer. Cancer Res 1998; 58: 4461-7.
• 9 Fernandez-Patron C, Zhang Y, Radomski MW. et al. Rapid release of matrix metalloproteinase (MMP)-2 by thrombin in the rat aorta: modulation by protein tyrosine kinase/phosphatase. Thromb Haemost 1999; 82: 1353-7.
• 10 Hejna M, Raderer M, Zielinski CC. Inhibition of metastases by anticoagulants. J Natl Cancer Inst 1999; 91: 22-36.
• 11 RxList. The Top 200 Prescriptions for 2000 by Number of US Prescriptions. Dispensed, [Website]. RxList®. Available: http://www.-rxlist.com/top200.htm 2000
• 12 Taliani MR, Agnelli G, Prandoni P. et al. For the Warfarin Optimal Duration Italian Trial (WODIT) Investigators. Incidence of cancer after a first episode of idiopathic venous Thromboembolism treated with 3 months or 1 year of oral anticoagulation. J Thromb Haemost 2003; 01: 1730-3.