Performance characteristics of the Indiana University Medical Center endometrial sampler (Tao Brush) in an outpatient office setting, first year's outcomes: recognizing histological patterns in cytology preparations of endometrial brushings.

Following successful hysterectomy-controlled trials, Tao brush endometrial cytology with liquid fixation was offered to clinicians for office use. This report recounts our first year's cytology and correlative histology outcomes. One hundred thirteen cases were accrued. Correlative tissue examinations comprising Pipelle (Prodimed, Neuilly-en-Thelle, France) biopsy, hysteroscopy and biopsy, dilatation and curettage, and hysterectomy were available at this institution for 59 cases. In 42 cases, cytology diagnoses could be compared to histology diagnoses. Twenty-five of 63 normal brushings were followed up. Fourteen were normal. Eleven Pipelle biopsies of cytologically atrophic endometrium were quantitatively limited and insufficient for diagnosis. Thirty-seven cases were abnormal, and 15 of these showed nuclear anaplasia. Twenty-eight of the abnormal cases were followed up. All correlative tissue examinations confirmed an abnormality. All 15 cases with nuclear anaplasia showed significant histopathology comprising atypical endometrial hyperplasia, endometrial intraepithelial neoplasia (EIN), endometrial intraepithelial carcinoma (EIC), and invasive adenocarcinoma. There were 13 inadequate endometrial brushings. Three cases had insufficient cellular material. The remaining 10 cases were cellular but were chiefly cervical/endocervical samples. Two of the cellular cases resulted from clinicians failing to replace the protective sheath over the brush bristles before removing the Tao brush from the endometrial cavity. The remaining 11 cases resulted from inaccessibility of the uterine cavity due to a tight or stenotic cervix. The Tao brush is a reliable uterine sampling device that performs well as a diagnostic tool for outpatient assessment of the endometrium of women with patent cervices. An advantage of endometrial cytology is that it accurately represents atrophic endometrium, and it is an effective case-finding tool for EIN and EIC. Women with tight or stenotic cervices are poor candidates for endometrial brushing, and may experience pain if the procedure is attempted. Diagn. Cytopathol. 2000;22:186-195.