Radiosensitivity of Cervical Cancer

Abstract

Methods for evaluating radiosensitivity of cervical carcinoma are described and experience in their application reported. Attempts made to predict biologic malignancy and degree of radiosensitivity from examination of pretreatment cervical biopsies showed that there is some correlation between histologic differentiation and malignancy of squamous carcinoma of the cervix. However, the available data are not sufficiently clear to establish correlation between histologic grade and either radiocurability or radiosensitivity. Histologic grading of cervical biopsies is of little or no value in predicting the prognosis of a patient with carcinoma of the cervix treated radiologically A previously reported correlation between the chromosomal population of cervical squamous carcinoma cells and radiosensitivity offers a new avenue of investigation which can be accomplished in the pretreatment stage. In most cases there was a correlation between higher ploidy (more than 60 chromosomes) of malignant cells and their radioresistant character, and between lower ploidy (less than 60 chromosomes) and radiosensitive behavior. Cervical biopsies obtained during the course of radiation therapy were examined in an attempt to correlate the histologic changes with the ultimate effect of radiation on the tumor and the survival of the patient. The presence or absence of tumor cells in vaginal smears during the monthmore » immediately following completion of radiation therapy was correlated with clinical outcome in 108 cases followed 2-4 1/2 yr. A cytological radiation response (RR) is more frequent in postmenopausal than in premenopausal women and increases with advancing age and supervoltage radiation. Gross characteristics of the tumor, stage of the lesion, and general health of the patient had no significant effect upon the frequency of or degree of RR. These data suggest that the cytological method of predicting RR is of limited value in those cases of very early or late cancer, the RR frequently being the converse of the expected and actual clinical outcome. The histological prognosis correlates well with the clinical outcome and is, generally, more reliable than cytological studies. Results of cytochemical technique were essentially the same as those with the histological technlque. The evaluation of biopsy specimens by the cytochemical method was, however, more difficult than with either of the other two techriques. The value of histological and cytochemical techniques combined appears greater than either technique alone, especially in predicting an unfavorable response. (TCO)« less