Rate of endometrial adenocarcinoma in women screened before and after implementation of the Bethesda 2001 reporting system

Objective: To assess the impact of the recommendation of the 2001 Bethesda System to report all benign-appearing endometrial cells seen in women aged ≥ 40 years on the frequency with which endometrial carcinomas are potentially detected as a consequence of Pap test reports that mention endometrial cells. Study Design: We identified all women diagnosed with endometrial adenocarcinoma who also had a Pap test during the preceding 6 months. The search was performed for 3-year periods before and after the date of implementation of Bethesda 2001. Results: Benign endometrial cells were reported for 589 women in the 3 years before Bethesda 2001 and for 3,810 women in the 3 following years. The number of endometrial malignancies found on follow-up in these women decreased from 8 in the 3 years before Bethesda 2001 to only 4 subsequently. The frequency of reporting atypical or malignant glandular cells, as well as the likelihood of finding endometrial malignancy on follow-up, did not significantly change. Conclusion: Despite a 6.5-fold rise in the frequency of reporting benign endometrial cells after Bethesda 2001, the frequency of subsequent diagnosis of endometrial malignancies did not increase.