OBJECTIVE To investigate the occurrence and origin of benign glandular cells in posthysterectomy vaginal smears and to propose a categorization for these cells under the Bethesda system. METHODS Among 4,986 posthysterectomy vaginal smears during a 3.5-year period, 82 patients were identified with smears containing benign glandular cells. The review of the smears, related biopsies and charts form the basis of this report. A control group of 236 posthysterectomy smears without glandular cells from the same period was reviewed. RESULTS Smears were available for review on 76 of 82 patients. All were within normal limits or showed benign cellular changes. All contained clearly benign glandular cells, most frequently present in groups. In all smears, pale pink-red intracellular mucin was identified either diffusely within the cytoplasm or within vacuoles. The glandular cells appeared as hybrid parabasal-endocervical type, squamous metaplastic or columnar cells. Associated cytologic findings included atrophy, inflammation, blood and repair. Reactive atypia was present in 10 (13%) cases. Biopsies were performed on 40 (48%), all showing benign changes. In four of five cases stained, intracellular mucin was seen within glandular cells. Chart review revealed that the patients' hysterectomies were performed for removal of a malignant tumor in 58 (71%) of the study group and in 100 (42%) in the comparison group and that 48 (58%) of the study group had received radiotherapy and/or chemotherapy, while only 26 (11%) of those in the comparison group had similar therapy. CONCLUSIONS The presence of benign glandular cells in posthysterectomy vaginal smears is an infrequent but not rare finding. This study indicated an association with benign processes and showed a frequent association with prior radiation or chemotherapy. A more appropriate designation under the Bethesda System is "benign cellular changes" rather than "glandular cell abnormalities." An aggressive workup does not appear to be warranted in this group of patients. We speculate that this phenomenon represents a metaplastic process, possibly secondary to radiation or chemotherapy.