Summary
Background Angiotensin-receptor blockers (ARBs) are a widely used drug class approved for treatment of hypertension,
heart failure, diabetic nephropathy, and, recently, for cardiovascular risk reduction. Experimental studies implicate
the renin-angiotensin system, particularly angiotensin II type-1 and type-2 receptors, in the regulation of cell
proliferation, angiogenesis, and tumour progression. We assessed whether ARBs affect cancer occurrence with a
meta-analysis of randomised controlled trials of these drugs.
Methods We searched Medline, Scopus (including Embase), Cochrane Central Register of Controlled Trials, Cochrane
Database of Systematic Reviews, and the US Food and Drug Administration website for studies published before
November, 2009, that included any of the seven currently available ARBs. Randomised controlled trials with an ARB
given in at least one group, with a follow-up of at least 1 year, and that enrolled at least 100 patients were included. Newcancer
data were available for 61 590 patients from five trials. Data on common types of solid organ cancers were available
for 68 402 patients from five trials, and data on cancer deaths were available for 93 515 patients from eight trials.
Findings Telmisartan was the study drug in 30 014 (85·7%) patients who received ARBs as part of the trials with
new cancer data. Patients randomly assigned to receive ARBs had a significantly increased risk of new cancer
occurrence compared with patients in control groups (7·2% vs 6·0%, risk ratio [RR] 1·08, 95% CI 1·01–1·15;
p=0·016). When analysis was limited to trials where cancer was a prespecified endpoint, the RR was 1·11 (95% CI
1·04–1·18, p=0·001). Among specific solid organ cancers examined, only new lung-cancer occurrence was
significantly higher in patients randomly assigned to receive ARBs than in those assigned to receive control (0·9%
vs 0·7%, RR 1·25, 1·05–1·49; p=0·01). No statistically significant difference in cancer deaths was observed (1·8% vs
1·6%, RR 1·07, 0·97–1·18; p=0·183).
Interpretation This meta-analysis of randomised controlled trials suggests that ARBs are associated with a modestly
increased risk of new cancer diagnosis. Given the limited data, it is not possible to draw conclusions about the exact
risk of cancer associated with each particular drug. These findings warrant further investigation.