Treating precancerous breast cells with agents such as tamoxifen limits the development of breast cancer in women genetically predisposed to the disease, according to research presented at the American Association for Cancer Research's annual Frontiers in Cancer Prevention meeting.

Researchers studied precancerous breast cells from patients with a hereditary predisposition to breast cancer called Li-Fraumeni syndrome. These cells become cancerous at more measurable rates in a laboratory environment and are therefore easier to monitor.

Patients with Li-Fraumeni syndrome are also at a higher risk for childhood cancers, soft-tissue sarcoma, leukemia, osteosarcoma, melanoma and colorectal cancers.

"To effectively treat or prevent cancer, it is important to understand the nature of how cells progress into the disease," said Brittney-Shea Herbert, PhD, cell biologist at the University of Texas Southwestern Medical Center in Dallas and lead investigator of the study. "Results from human clinical trials take many years to generate so it is imperative that alternate testing forms, such as precancerous cells, be used to determine the effectiveness of precancerous agents."

Treatment of precancerous Li-Fraumeni syndrome breast cells with some but not all chemopreventive agents decreased the development of cancer in vitro (test tube). The chemopreventive agents used in the study did not negatively affect normal cell growth or present significant side effects. Tamoxifen had the strongest effect in preventing the frequency of indefinite cell reproduction at nontoxic levels.

Other sources: American Association for Cancer Research