Progestin therapy of complex endometrial hyperplasia with and without atypia.

Objective: To assess the likelihood of histologic persistence/progression of complex hyperplasia and atypical hyperplasia among women treated with progestin compared with those not treated, with attention to type, dose, and duration.

Methods: This was a cohort study at an integrated health plan of women, ages 18-85 years, with complex or atypical hyperplasia on independent pathology review with a second endometrial specimen in the 2-6 months after the index diagnosis. Progestin therapy between index diagnosis and follow-up biopsy was determined from the pharmacy database. Medical record abstraction was performed. Relative risks (RRs), adjusted for age and body mass index, were calculated.

Results: Among 185 women, average age 55.9 years, follow-up 16.1 weeks, 115 had complex and 70 had atypical hyperplasia. Among women with complex hyperplasia, 28.4% of those treated with progestin and 30.0% of those not treated had persistence/progression (RR 1.20, 95% confidence interval [CI] 0.53-2.72). Among women with atypical hyperplasia, 26.9% of those treated with progestin and 66.7% of those not treated had persistence/progression (RR 0.39, 95% CI 0.21-0.70); there was a suggestion that use of at least a medium dose, or a duration of at least 3 months, was associated with a particularly low probability of persistence/progression.

Conclusion: Although progestin treatment of women with atypical hyperplasia was associated with a substantial increase in the likelihood of regression of the lesion during the ensuing 2-6 months, persistence/progression was nonetheless present in more than one quarter of treated women. Regression of complex hyperplasia without atypia was common whether progestin had or had not been used.