In recent years, the prevalence of renal cancer has increased, in part due to the detection of tumors during imaging studies for non-related health concerns. While Agent Orange, a herbicide used during the Vietnam war, has been previously linked to a variety of types of cancers in Vietnam veterans, new data from researchers at the Veterans Affairs Medical Center in Shreveport, LA, indicates that there may be a connection between veterans' in-country exposure and subsequent development of renal cancer. The findings were presented to reporters during a special press conference at the Walter E. Washington Convention Center in Washington, DC on Sunday, May 15 at 11:30 a.m. during the 106th Annual Scientific Meeting of the American Urological Association (AUA). The session will be moderated by Anthony Y. Smith, MD.

Researchers at the Overton Brooks VAMC in Shreveport examined charts for 297 patients diagnosed with renal cancer between 1987 and 2009. Of these patients, 13 (4 percent), ranging in age from 39 to 63 years at time of presentation, claimed exposure to Agent Orange. Eleven of these patients underwent surgical treatment. Authors reviewed age at presentation, tumor size, side of lesion, pathology and survival in the 10 patients with documented exposure to Agent Orange for which pathology reports were available.

Of these patients, 90 percent had clear-cell cancers, which typically have a worse prognosis than papillary tumors, which appeared in one of the patients. One patient had combined clear-cell and papillary cancers. Node sampling was negative in all. Mean follow up was 54 months. Four patients developed metastatic disease and one patient died from his cancer.

"We know that the chemicals in Agent Orange were extremely toxic, and are known to cause cancer," Dr. Smith said. These data indicate that we may need to better determine whether exposure to these chemicals should be considered a risk factor for kidney cancer."

About Agent Orange

Agent Orange is a combination of two synthetic compounds known to be contaminated with the dioxin tetrachlorodibenzo-para-dioxin (TCDD) during the manufacturing process. Named for the color of the barrel in which it was stored, Agent Orange was one of many broad-leaf defoliants used in Vietnam to destroy enemy ground cover. It is estimated that more than 20 million gallons of the chemicals, also known as "rainbow herbicides" were used between 1962 and 1971; approximately half the herbicides were Agent Orange. In 1997, the International Agency for Research on Cancer re-classified TCDD as a Group 1 carcinogen, a classification that includes arsenic, asbestos and gamma radiation.

American Urological Association