Sensitivity of ThinPrep Test by Self-collected Vaginal Tampon in Women with Abnormal Pap Smear

Abstract

Abstract

Objective: To compare the sensitivity of the ThinPrep test by self-collected vaginal tampon for cervical cytology in women with abnormal Pap smears and their pathological diagnosis

Design: Diagnostic test

Setting/population: Eighty-one women with abnormal results of Pap smear within the previous 6 months were recruited from the colposcopy clinic of Department of Obstetrics and Gynaecology, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok, Thailand from September 2009 to May 2010.

Methods: Participants inserted a vaginal tampon on the morning and removed it before a colposcopic examination on the afternoon. Vaginal tampons were then immersed into a vial of ThinPrep Presrv-Cyt solution and sent to a cytopathologist for analysis. Results were compared to the final pathological diagnosis.

Outcome measures: Outcomes of the ThinPrep test by self-collected vaginal tampon detecting any abnormalities (ASC-US, ASC-H, LSIL, HSIL, SCC, AGC, AGC-FN, AIS, Adenocarcinoma) compared to final pathological diagnosis.

Results: The ThinPrep test with self-collected vaginal tampon detected abnormalities with the sensitivity of 35.1%, specificity of 87.5%, PPV of 86.9% and NPV of 36.2%. The sensitivity of our ThinPrep test to specifically diagnose CIN 3 was 50% when compared to the final pathological diagnosis. The adequacy of specimens for diagnosis with our ThinPrep test was 67%.

Conclusions: The ThinPrep test obtained by self-collected vaginal tampon was an alternative method for detection of abnormal cytology in women with abnormal Pap smear. Further studying of this technique as a follow-up method for women with abnormal cervical pathology after colposcopy evaluation would be interesting.

Keywords: Cervical cancer, conventional Pap smear, cytology, self- collected vaginal tampon, ThinPrep