Breast Cancer
Breast cancer has various risk factors, and DES exposure is among them. Studies have indicated a small increase in risk among DES Daughters throughout their lifetime. The most recent analysis shows up to a 30% increase in breast cancer risk for DES Daughters in their 40s. The excess risk seems to decrease after age 50, although breast cancer risk in general tends to rise with age, independent of DES exposure. For DES Mothers, the breast cancer risk is approximately 30% higher than it is for women who were not given DES during pregnancy.
No specific tumour type or gene mutation has been linked with DES Daughter breast cancer. Researchers suspect prenatal DES exposure may accelerate the growth of cells that develop into breast cancer. This potential for rapid growth contributes to the increased risk and incidence of breast cancer at an earlier age for DES Daughters.
The additional breast cancer risk for DES Daughters should be considered when deciding about hormone replacement therapy (HRT). Only the lowest dose of HRT for a short period should be considered when necessary. This recommendation applies to all women, particularly DES Daughters and DES Mothers.
Researchers with the National Cancer Institute DES Follow-up Study are also investigating whether bra cup sizes may explain the DES Daughter link to breast cancer.
Clear Cell Adenocarcinoma (CCA) of the Vagina and Cervix
The risk for this rare cancer is estimated at 1 in 1,000. It was previously believed DES Daughters over age 30 were no longer at risk, but CCA remains a lifelong concern, with cases reported in Daughters older than 50, when CCA can also occur in the unexposed population. Researchers are monitoring for a potential spike in post-menopausal DES Daughters. A population-based analysis by CDC researchers suggests an elevated CCA risk as DES Daughters age. Studies are ongoing, but there does not appear to be an upper age limit for this cancer in DES Daughters.
Prostate Cancer
DES Sons are reaching or are in the age range for prostate cancer occurrence, but there have been no reports of increased incidence among them. Animal studies suggest a possible heightened risk for DES-exposed men, leading some researchers to speculate that DES Sons could be at higher risk and should remain vigilant.
Testicular Cancer
No testicular cancer specifically associated with DES has been found; however, research indicates congenital abnormalities like undescended testicles predispose men to testicular cancer. Therefore, DES Sons and DES Grandsons, who have a higher rate of such anomalies, might be considered a high-risk group. Regular testicular self-exams are recommended for all men.