Radiation-induced benign glandular cells in posthysterectomy smears: a cytomorphologic and clinical analysis

In this retrospective study, we aimed to investigate the frequency and cytomorphologic characteristics of benign glandular cells (BGCs) in hysterectomized individuals. We also discussed the possible effect of radiation therapy on these cells. We reviewed our cytopathology archive material through a 5.5-year period and found 1460 posthysterectomy vaginal smears. Of these, 508 smears were from patients who had undergone hysterectomy for a gynecological malignancy. Review of this vaginal cytology material revealed 17 posthysterectomy patients whose smears contained BGCs. We obtained detailed clinical information in 16 of these. In addition to routine Papanicolaou staining, mucicarmine stain was also used to demonstrate cytoplasmic mucin in some cases. All the patients had a history of gynecological malignancy and had radiation therapy. Glandular cells appeared singly or in rows and honeycomb groups and did not show cytologic atypia. We concluded that radiation might give rise to a metaplastic process in which basal cells of squamous epithelium of the vagina transform into glandular cells. Most probably this process is independent of radiation dosage and period and is irreversible. We also propose that the possibility of encountering glandular cells in posthysterectomy smears is higher than expected, if the mucin stains have been used for the microscopic examination.