Management of Insufficient Endometrial Biopsy for Investigation of Premenopausal Abnormal Uterine Bleeding

Abstract

Objectives: To evaluate the risk of endometrial pathology and options of subsequent management in patients with abnormal uterine bleeding whose endometrial biopsies were reported as insufficient.
Methods: This was a retrospective study on insufficient endometrial biopsies performed for the investigation of premenopausal abnormal uterine bleeding in Pok Oi Hospital, Hong Kong, from 1 January 2009 to 31 December 2011. The subsequent management and outcomes were then analysed.
Results: A total of 2612 patients underwent outpatient endometrial biopsy during the study period. Among these, 133 (5.1%) of endometrial biopsies were reported as “insufficient tissue for diagnosis”; eight patients were lost to follow-up. The median (interquartile range) duration of follow-up for the remaining 125 (94%) patients was 384 (19-1113) days. A total of 49 (39%) patients had no further invasive investigations; of these, four patients eventually underwent hysterectomy for benign disease unrelated to endometrial hyperplasia or carcinoma. Overall, 76 (61%) patients had further investigations, 15 had repeat endometrial sampling and 61 had hysteroscopy with endometrial biopsy. Hysteroscopy showed polyps or fibroids in 16 (26%) patients; of these, nine underwent polypectomy or hysteroscopic resection. Endometrial hyperplasia or malignancy was not detected in any subject. Furthermore, endometrial hyperplasia did not develop de novo during the study period. There was one case (0.8%)
of adenocarcinoma diagnosed 608 days after a normal repeat endometrial biopsy.
Conclusion: The risk of endometrial hyperplasia and carcinoma was low after an insufficient endometrial biopsy for premenopausal abnormal uterine bleeding. Patients with persistent symptoms should be further investigated. Benign polyps and fibroids amenable to hysteroscopic treatment were common and hysteroscopy should be considered when further investigation is indicated.