Papanicolaou and thin-layer cervical cytology with colposcopic biopsy control. A comparison
Harkness, C.Blair.; Theofrastous, J.P.; Ibrahim, S.N.; Galvin, S.L.; Lawrence, H.C.
Journal of Reproductive Medicine 48(9): 681-686
2003
ISSN/ISBN: 0024-7758 PMID: 14562631 Document Number: 553923
OBJECTIVE: To compare the accuracy of conventional Papanicolaou and fluid-based, thin-layer cervical cytology. STUDY DESIGN: Cervical cytology was performed in duplicate on women who presented for cervical screening. Papanicolaou and thin-layer (ThinPrep(R), Cytyc Corp., Boxborough, Massachusetts) cytologic samples were collected simultaneously using a split-sample method. Cytologic slides were read and reported independently. Clinical follow-up was based on the most abnormal result. Colposcopy was performed as clinically indicated, and biopsy results were compared with cytologic diagnoses. RESULTS: Three thousand samples were compared. Papanicolaou and thin-layer results were significantly different (P=.0001), with identical diagnoses in 1,844 (61%) of patients. Eighty thin-layer (2.7%) and 177 Papanicolaou (5.9%) samples were read as limited or unsatisfactory (P<.0001). The rates of atypical squamous cells of undetermined significance (ASCUS) were not statistically different (P=.06). Thin-layer cytology was read more often as low grade squamous intraepithelial lesion (P=.001) or high grade squamous intraepithelial lesion (P=.006). Colposcopy with biopsy was performed on 291 patients. With ASCUS considered an abnormal result, thin-layer cytology was more sensitive (91% vs. 85%) but had lower positive predictive value (69% vs. 74%) than Papanicolaou cytology for the presence of cervical neoplasia. CONCLUSION: Papanicolaou and thin-layer cervical cytology yielded significantly different information. Thin-layer cytology yielded significantly fewer unsatisfactory results and was more sensitive for identifying cervical intraepithelial neoplasia.