Epidemiologic aspects and factors related to survival in 384 Registry cases of clear cell adenocarcinoma of the vagina and cervix.

Three hundred and eight-four cases of clear cell adenocarcinoma of the vagina and cervix accessioned in the Registry as of December 31, 1978, have been analyzed. The annual incidence of these tumors has been found to correspond closely to the estimated usage of diethylstilbestrol (DES) for pregnancy support in the United States. The annual incidence of the DES-associated cases appears to have dropped in the United States in the past 2 years in comparison to 1973 to 1975. The risk of tumor development appears to be higher in young women exposed to DES early in intrauterine life than in those exposed later. The carcinomas are rare before the age of 14 years and an irregular peak in the age-incidence curve appears between 17 and 21 years followed by a decline. The 5-year survival rate is better for women over the age of 19 years than for younger patients, and a higher frequency oral contraceptive usage did not appear to influence the behavior of the tumor and the improved survival in those using this medication appears to be related to greater medical surveillance.