RADIATION-INDUCED ATYPIA OF ENDOCERVICAL EPITHELIUM - A HISTOLOGICAL,IMMUNOHISTOCHEMICAL AND CYTOMETRIC STUDY

Radiation-induced changes of the endocervical glandular epithelium hav e not been well characterized. Ten specimens (nine from hysterectomy, one from biopsy) from patients with therapeutic radiation to the pelvi s for genitourinary or gastrointestinal cancer were examined by histol ogical, immunohistochemical, flow cytometry and image cytometry analys is, and comparison was made to 10 cases of adenocarcinoma in situ (ACI S) of the cervix. Patients ranged from 34 to 68 years of age and recei ved at least 3600 cGy total dosage to the pelvis. Hysterectomy or biop sy was performed six weeks to 17.5 years after completion of radiother apy, Gross examination of the hysterectomy specimen revealed fibrosis, induration, stenosis, surface irregularity or an unremarkable cervix. Microscopic examination of endocervical glandular epithelium showed s parse, widely spaced glands which were tubular or dilated. Epithelium was simple cuboidal or flattened and consisted of large cells with at most a slight increase in NIC ratio, well-defined intercellular border s and eosinophilic or finely vacuolated cytoplasm. Nuclei frequently s howed loss of polarity, one or two prominent eosinophilic nucleoli, an d evenly dispersed chromatin; only occasional hyperchromatic cells wer e seen. Rare scattered cells were immunoreactive for carcinoembryonic antigen in seven of nine cases, One case was hyperdiploid by both flow cytometry and image cytometry. The remaining cases were diploid by fl ow cytometry and either diploid (five cases) or hypodiploid (four case s) by image cytometry. These findings indicate that pelvic radiation t herapy causes characteristic histologic changes in endocervical glandu lar epithelium that are distinct from those of ACIS of the cervix, Cyt oplasmic CEA staining frequently is focally positive and does not allo w distinction from ACIS.