Study Links Agent Orange to Prostate Cancer in Vietnam Vets

"I'm not totally convinced," Roth said, noting that the study relies on self-reported exposure to Agent Orange, without other objective proof of exposure or the amount of exposure.

Roth speculated that because all study participants who reported being exposed to Agent Orange were given thorough screening tests for prostate cancer, more cancers were found. "I can almost guarantee you're going to find more cases of prostate cancer," he said.

"I'm not saying that there is not possibly some relationship, but I don't think that this paper necessarily proves it," Roth said. "But I think you could pick almost any exposure and increase screening, and you are going to find more cases, whether or not the agent is responsible for more cases or not."

Dr. Michael J. Thun, vice president of epidemiology and surveillance research at the American Cancer Society, agreed that the findings were interesting but don't prove a connection between prostate cancer and Agent Orange.

"The finding is provocative, but it's hard to know how to interpret it, unless it can be replicated in other studies," Thun said.

More information

For more on prostate cancer, visit the American Cancer Society.

SOURCES: Karim Chamie, M.D., resident physician in urology, VA Northern California Health Care System; Bruce Roth, M.D., professor, medicine and urologic surgery, Vanderbilt University, Nashville, Tenn.; Michael J. Thun, M.D., vice president of epidemiology and surveillance research, American Cancer Society, Atlanta; Sept. 15, 2008,Cancer, early online release