A Best Evidence Topic was undertaken to systematically review the evidence 
regarding the use of NSAIDS in breast cancer patients. The search strategy 
generated 149 titles, of which six were best placed to answer the clinical 
question. These included three prospective cohort studies, two retrospective 
cohort studies and one case control study, examining a total of 18,415 breast 
cancer patients. The study methodologies were highly variable and all relied on 
approximate measures of NSAID consumption. There is limited evidence that use of 
aspirin and non-aspirin NSAIDs may be associated with decreased breast cancer 
mortality and all-cause mortality in patients diagnosed with breast cancer. 
Optimum type and dosage of NSAID for this purpose remains unclear. There is a 
need for large-scale randomised controlled trials to further clarify.