Objective: To determine the current situation regarding the epidemic of clear cell adenocarcinoma of the vagina and the uterine cervix (CCAC) in relation to the exposure in utero to diethylstilbestrol (DES).
Design: Descriptive.
Methods: Patients with CCAC of the uterine cervix or vagina born after 1946 and diagnosed in the period 1969-2005, were identified through the Nationwide network and registry of histo- and cytopathology in the Netherlands and from 2003 onwards through the Netherlands Cancer Registry. Exposure data and clinical data were obtained by means of questionnaires and medical records. The histology slides of tumours were reviewed. For the patients who did not provide consent, only the date of diagnosis and age at diagnosis were known (n = 10).
Results: Up to 2005, 144 CCAC patients were registered. Age at diagnosis varied from 8-54 years (mean: 28 years). In the years 1981-2000, the number of new diagnoses in 4 successive 5-year periods was fairly stable (n=26-30) but it was considerably lower in 2001-2005 (n=13). Of the patients whose history of intrauterine exposure to DES was known, 62% had been exposed (76/122). The mean age at diagnosis was 24 years for exposed patients compared to 32 years for non-exposed patients. The 10-year survival rate was 78% (95% CI: 68-87) for exposed and 69% (95% CI: 56-82) for non-exposed patients.
Conclusion: Since 2000, the incidence of CCAC of the vagina and cervix has decreased markedly compared to the situation in the 1980s and 1990 s. In particular, the number of patients with CCAC exposed in utero to DES has decreased. Whether this decrease shall continue over the coming years remains to be seen.