Dezheng Huo, MD
In a letter to the editor of The New England Journal of Medicine, Dezheng Huo, MD, of the University of Chicago, Chicago, and colleagues described the long-term outcomes of women with vaginal and cervical clear cell adenocarcinoma associated with prenatal exposure to the synthetic nonsteroidal estrogen diethylstilbestrol (DES). As noted by the authors, women with DES-related clear cell adenocarcinoma are aging into their 50s and 60s, but the effect of this condition across their overall life span has not been well-defined.The report included a total of 695 women with clear cell adenocarcinoma in the Registry for Research on Hormonal Transplacental Carcinogenesis followed through 2014.
A total of 219 patients died during median follow-up of 22.7 years, representing 20-year overall survival of 69%. Overall survival at 5 years was 86.1% in patients with documented prenatal DES exposure vs 81.2% among those without documented exposure; however, 20- year probability of survival was similar in the 2 groups. In an analysis adjusting for tumor stage, histologic type, and age, the adjusted hazard ratio for mortality for the documented vs nondocumented group was 0.63 (95% confidence interval [CI] = 0.42–0.94) for ≤ 5 years and 0.89 (95% CI= 0.59–1.35) for > 5 years. Patients with clear cell adenocarcinoma had greater mortality risk across their life span. Compared with the general U.S. population, risk of death among women with DES-related clear cell adenocarcinoma was 27 times higher for women aged between 10 and 34 years, 5 times higher for those aged 35 to 49 years, and 2 times higher for those age 50 to 65 years.
The authors noted that the excess mortality risk among patients aged 35 to 49 years mainly reflected late recurrences, whereas the excess risk after age 50 years might reflect additional life-threatening conditions among women with prenatal exposure to DES. They concluded, “It is therefore important to continue the surveillance of this unique cohort of patients with DES-related clear cell adenocarcinoma to examine their health conditions late in life.” ■