Increasing the sensitivity of endocervical curettings by performing ThinPrep® Pap on transport container fluid: is diagnostic material going down the drain?

Abstract

Objective: The sensitivity of endocervical curettage (ECC) can be suboptimal because of limited epithelial tissue. The false-negative rate for ECC in patients with cervical intraepithelial neoplasia involving the endocervical canal has been reported to be 45%. ECC samples are transported to pathology in formalin- or saline-filled containers; this fluid is discarded after the specimen has been submitted. We evaluated the utility of performing liquid-based cytological preparations from ECC transport container fluid as a way to increase the sensitivity of ECC specimens.

Methods: Consecutive ECC specimens received at one of the two participating institutions were selected prospectively. A surgical pathology mesh bag was placed over a ThinPrep(®) CytoLyt(®) solution container, and the specimen was filtered through the bag, collecting the transport fluid in the container. The CytoLyt(®) was processed to obtain a container fluid ThinPrep(®) (CF-TP) liquid-based Papanicolaou (Pap) slide. The CF-TP slides were reviewed and the findings were compared with those from the ECC and follow-up specimens.

Results: The cohort included 53 patients. Discrepancies between CF-TP and ECC were seen in 14 of the 53 patients (26%); a more significant lesion was identified in CF-TP relative to ECC in 13 of these cases. CF-TP diagnosis was confirmed in eight of 11 cases with histological follow-up. A positive CF-TP result was confirmed by histology in six of nine cases with negative ECC.

Conclusions: Combining the pathological evaluation of ECC specimens with liquid-based cytology performed on the transport container fluid can increase the diagnostic sensitivity of the ECC procedure for the detection of cervical lesions.

Keywords: Pap tests; colposcopy; endocervical curettage; liquid-based cytology; sensitivity.