Cytologic correlates of papillary immature metaplasia (immature condyloma) of the cervix.

Papillary immature metaplasia (PIM) of the cervix (immature condyloma) is a variant of low-grade squamous intraepithelial lesions (LSIL). It is frequently associated with human papillomavirus (HPV) types 6 and 11. The purpose of this study was to characterize the cytologic changes associated with this lesion. We analyzed 10 cases of PIM from our files and reviewed the Papanicolaou smears taken proximate to the time of the biopsy. Four cases had either reactive epithelial changes (2 cases) or cytologic findings typical of low-grade SIL, with koilocytosis (2 cases). Six cases displayed a spectrum of metaplastic cells with varying maturation that ranged from atypical reactive cells to atypical immature metaplastic cells. Binucleation was common. Some cells exhibited features characteristic of SIL, although the degree of nuclear atypia generally was less than that associated with high-grade SIL. Papanicolaou smears from all cases were interpreted as atypical (ASCUS) metaplasia or low-grade SIL. Follow-up biopsy in one case revealed a PIM in association with a high-grade SIL, the latter undiagnosed by smear alone. PIM is a distinct histologic entity that can present with a spectrum of cytologic findings. Its recognition histologically can resolve some cytologic/histologic discrepancies. Confusion with an immature HSIL or atypical immature metaplasia can occur in some instances and the diagnosis of PIM by cytology alone is not recommended, unless the diagnosis is qualified.