Endometrial brush biopsy (Tao brush). Histologic diagnosis of 200 cases with complementary cytology: an accurate sampling technique for the detection of endometrial abnormalities.

We examined 200 cases of endometrial brush biopsy (EBB) using the Tao brush and correlated findings with histologic findings from subsequent dilatation and curettage (D&C) or hysterectomy specimens. Diagnosis by EBB relied mainly on histologic evaluation of H&E-stained tissue sections and was complemented by additional cytologic smear examination. EBB correctly detected the following cases: endometrioid adenocarcinoma, 3; complex hyperplasia with atypia, 1; simple hyperplasia without atypia (SH), 2; and benign endometrium, 177. In 3 cases the diagnosis of atrophic endometrium was made by EBB; corresponding D&C specimens were nondiagnostic. Five cases of SH were interpreted by EBB as proliferative endometrium, and 13 endometrial polyps were not identified by EBB. Nine samples were nondiagnostic. Sensitivity and specificity were 100% for detecting atypical hyperplasia and carcinoma. However, it was difficult for EBB to distinguish SH from disordered proliferative endometrium or to diagnose endometrial polyps. We found that diagnosis by EBB is reproducible; a second pathologist blinded to histologic follow-up correctly identified all adenocarcinoma/atypical hyperplasia cases. EBB is an accurate, safe, and easy procedure that is well tolerated by patients and should be considered in the initial evaluation of high-risk outpatients.