NEW YORK (CNNMoney.com) - Celebrex, an arthritis painkiller from Pfizer, could be used to prevent colorectal cancer, according to studies revealed today by the American Association for Cancer Research.

Cox-2 inhibitors, anti-inflammatory drugs that are generally used as arthritis painkillers, help prevent colorectal and breast cancer by preventing the formation of pre-malignant tumors, according to studies announced at a AACR conference in Washington, D.C. The studies used Celebrex, which is based on celecoxib compound and is marketed as an anti-inflammatory joint treatment.

"This is a growing field, catching cancer at the preventative levels," said Pfizer's cancer research director Craig Eagle. "There's an immense amount of data that shows [Celebrex] could be researched in other areas of cancer, as well."

A randomized study, conducted by researchers with Adenoma Prevention with Celecoxib Study, of 2,035 patients showed that Celebrex reduced the formation of pre-malignant tumors by 66 percent. These results were similar to a previous study, conducted by researchers for the Prevention of Colorectal Sporadic Adenomatous Polyps, which showed the Celebrex shrunk the size and number of tumors. Pfizer helped fund the studies.

Cox-2 inhibitors have been linked to serious health problems. Vioxx, made by Merck (up $0.16 to $35.39, Research), was pulled from the market in 2004 after studies showed increased risks of heart disease and stroke. Since that time, about 10,000 lawsuits have been filed against the company by former Vioxx patients and their family members, who blame the drug for heart attacks and deaths. Vioxx had annual sales of $2.5 billion before it was withdrawn.

Pfizer (up $0.22 to $25.14, Research) pulled its $1.3 billion Cox-2 inhibitor Bextra from the market in 2005, but kept Celebrex on the market with a revised warning label. Celebrex sales totaled $3.3 billion in 2004 but prescriptions have plunged.

Pfizer's stock price was up slightly following the announcement, but the study results might not be strong enough to save lagging sales for Celebrex.

"Celebrex is a drug with baggage," said Les Funtleyder, analyst for Miller Tabak. "On the margins, [the study results] are positive, but they're trying to help a product with some issues. It would be more helpful for Celebrex if Merck would win a few of these [Vioxx] cases."

Will Vioxx ever get back on the market? To find out, click here.

To find out the latest in the Vioxx trials, click here.