DNA analysis cervical and vaginal cancer cells during radiotherapy by rapid high-resolution cytometry.

The DNA content of the nuclei of cancer cells of 12 cases of cervical cancer and 2 cases of vaginal cancer, treated with radiotherapy, were studied in 50 specimens. Specimens were taken from each case before radiotherapy and at the totals of 1,000 rad, 2,000 rad, 3,000 rad and 4,500 rad (or 5,000 rad). All specimens were stained by the Papanicolaou method and were analyzed by rapid high-resolution cytometry. Total optical density, mean nuclear area and the 5N-exceeding rate (5NER) increased gradually following irradiation. Cancer cells disappeared in good response cases before 3,000 rad. Eight smears with a 5NER under 100 at the dose of 3,000 rad or more seemed to be poor response cases. Low 5NER and low mean nuclear areas were observed in both patients who died with persistent disease after radiotherapy, as well as in one case treated with chemotherapy for persistent disease after radiotherapy.