Jim Kling

October 26, 2012

LAS VEGAS, Nevada — A meta-analysis of observational studies suggests that statins have a protective effect against esophageal cancer, particularly among patients with Barrett's esophagus. The results were presented here at the American College of Gastroenterology 2012 Annual Scientific Meeting and Postgraduate Course.

Rates of esophageal cancer are rising in the United States, particularly esophageal adenocarcinoma in patients with Barrett's esophagus. Preclinical and observational studies have suggested that statins have a protective effect against esophageal cancer.

The researchers searched MEDLINE, Embase, and Web of Science (from inception up to May 2012), and reviewed all article bibliographies.

Included studies had to evaluate and clearly define exposure to statins, had to report esophageal cancer outcomes, and had to report or provide data to estimate relative risk (RR) or odds ratios (OR). The researchers used the random-effects model to derive summary OR estimates maximally adjusted for potential confounders.

The analysis included 13 studies, which encompassed about 9000 cases of esophageal cancer in 995,687 patients. It revealed that statin use was associated with a 30% reduction in the incidence of esophageal cancer (adjusted OR, 0.70; 95% confidence interval [CI], 0.57 to 0.86).

When the 7 high-quality observational studies (Newcastle–Ottawa score above 7) were analyzed, a similar effect was seen (adjusted OR, 0.70; 95% CI, 0.56 to 0.88; Cochran's Q test, P = .13; I2 = 40).

The researchers also analyzed a subset of studies focused on patients with known Barrett's esophagus (5 studies, 312 cases of esophageal adenocarcinoma in 2125 patients), and found that after adjustment for confounders, statin use was associated with a 41% decrease in the risk for esophageal adenocarcinoma (adjusted OR, 0.59; 95% CI, 0.45 to 0.78).

To prevent 1 case of esophageal adenocarcinoma in patients with Barrett's esophagus, the number needed to treat is 389. The protective effect was greater with the combined use of statins and nonsteroidal antiinflammatory medications or aspirin (adjusted OR, 0.28; 95% CI, 0.14 to 0.56).

"Some of the studies adjusted for the effect of aspirin, and statins were still independently predictive [of lower risk]," said Siddharth Singh, MBBS, a gastroenterologist at the Mayo Clinic in Rochester, Minnesota, who presented the research.

"The findings are encouraging, but aren't [the last word], Dr. Singh noted. The next step is a randomized controlled trial in which some patients at high risk for esophageal adenocarcinoma get statins and other do not. The rates of cancer also need to be assessed, he added.

The cancer risk associated Barrett's esophagus is still poorly understood, according to James C. Reynolds, MD, chair of medicine at the Drexel University College of Medicine in Philadelphia, Pennsylvania, who attended the presentation.

"I think the most important issue is understanding the actual risk [of Barrett's esophagus leading to esophageal cancer]. No good studies have been done to really pinpoint what that is," Dr. Reynolds told Medscape Medical News.

The study bolsters the idea that esophageal cancer can be prevented with drugs. "If you can reduce the risk of advancing from metaplasia alone to cancer, then you can reduce the need for interventions, the expense of therapy, and, quite frankly, the fear that [patients] have, and that's important," he explained.

"What this study did was add to our confidence that, in addition to proton pump inhibitors and aspirin, a third agent, statins, is useful. Any other intervention, endoscopic or surgical, has got to be compared with the idea that medical therapy alone reduces the risk by 70% with very safe drugs that most of these patients are going to be on anyway," Dr. Reynolds added.

Dr. Singh and Dr. Reynolds have disclosed no relevant financial relationships.

American College of Gastroenterology (ACG) 2012 Annual Scientific Meeting and Postgraduate Course: Abstract 1. Presented October 22, 2012.