Five-Year Follow-Up After Cervical Cytology And Histology Discordance: A Retrospective Cohort Study

Background Cervical smear cytology and colposcopic biopsy histology are prone to error at both collection and interpretation stages, leading to a large number of discordant cases.Aims Investigation of five-year outcomes for women who have cervical cytology that is discordant and higher grade than histology results.Materials and Methods A retrospective cohort study was carried out for 111 women with cervical cytology discordant and higher grade than histology, after cytopathological review, over a three-year period. Five-year follow-up data were reviewed to identify the highest level of pathology seen within five years from the discordance.Results Women with atypical squamous cells with possible high-grade change (ASC-H) cytology and negative biopsy (n = 28) had a 46% chance of high-grade histological disease within 5 years; with cervical intraepithelial neoplasia grade 1 (CIN1) histology (n = 20), this was reduced to 30%. With high-grade cytology and negative histology (n = 23), 48% had high-grade disease within five years, including one case of invasive disease; with CIN1 histology 50% had high-grade disease within five years.Conclusions This study demonstrates a 30-50% chance of high-grade disease within five years, in the setting of ASC-H or high-grade cytology with a negative or low-grade colposcopic biopsy. This highlights that in the setting of cytology and histology discordance, at least one of the tests indicating high-grade pathology warrants the need for treatment or close ongoing surveillance.