Faculty Collaboration Database

False positive diagnosis in conventional and liquid-based cervical specimens. Acta Cytol 2004;48(3):363-71

Date

06/15/2004

Pubmed ID

15192952

DOI

10.1159/000326386

Scopus ID

2-s2.0-2442680506 (requires institutional sign-in at Scopus site)   16 Citations

Abstract

OBJECTIVE: To examine conventional and liquid-based cervical smears falsely diagnosed as malignant at our institution and to investigate, through cytologic-histologic correlation, factors influencing false positive diagnoses.

STUDY DESIGN: Cervical cytologic diagnoses of malignancy from May 1, 1995, to April 30, 2001, were retrieved through a computer search. A retrospective review of hospital records and pathology reports was performed. Cases identified as false positives were reviewed and correlated with histologic follow-up specimens.

RESULTS: A group of 68 patients with malignancy reported on cervical smears and with histologic follow-up was identified. Conventional smears numbered 32 (47%); the remaining 36 (53%) were liquid-based samples. Of the total, 7 false positive cases (10.3%) were identified in 4 conventional and 3 liquid-based preparations. Cytologic diagnosis in these cases was squamous cell carcinoma in 5 and adenocarcinoma in 2. On histologic follow-up, all 7 patients were ultimately found to have high grade squamous intraepithelial lesions (HSILs) without invasion. Review of the original slides confirmed most, or all, of the following features in all cases: major cellular pleomorphism, extensive cytoplasmic keratinization, intense nuclear pyknosis, background necrosis and severe atrophy.

CONCLUSION: There was no significant difference in rates of false positive diagnoses between conventional (12.5%) and liquid-based (8.3%) samples. The chief reason for overdiagnosis in this series was the capacity of HSIL to exfoliate cells mimicking invasive malignancy, particularly when keratinized and especially in an atrophic milieu. The other cause of false positivity was superimposition of inflammation and atypical reparative change on a background of HSIL, which then suggested invasion.

Author List

Mount S, Harmon M, Eltabbakh G, Uyar D, Leiman G

Author

Denise S. Uyar MD Professor in the Obstetrics and Gynecology department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Adenocarcinoma
Adult
Aged
Aged, 80 and over
Carcinoma, Squamous Cell
Cytodiagnosis
Diagnosis, Differential
False Positive Reactions
Female
Follow-Up Studies
Hospital Records
Humans
Middle Aged
Retrospective Studies
Specimen Handling
Uterine Cervical Neoplasms
Vaginal Smears