Radiation-induced tumor regression as a prognostic factor in patients with invasive cervical cancer.

Radiation-induced tumor regression was evaluated as a prognostic factor in 200 patients with invasive cervical cancer treated at the University of Kentucky Center during the years 1973-1977. Radiation responses were classified as complete (Type A), intermediate (Type B), or incomplete (Type C) based upon pelvic examination findings one month following completion of therapy. Patients with Type A response to radiation had a recurrence rate of 5%, as compared with 27% in patients with a Type B response and 85% in patients with a Type C response. The direct relationship between radiation response and the incidence of tumor recurrence was observed in all stages of disease. Seventy-five percent of patients with Stages IB and IIB disease and a Type C response to radiation developed recurrent cancer, and tumor recurrences were confined to the central pelvis in the majority of cases. Patients with keratinizing squamous cell cancers had the lowest incidence of complete response to radiation. These findings suggest that careful observation of cervical cancer throughout radiation therapy can provide prognostically significant information concerning radiation-induced tumor regression. The therapeutic implications of this data is discussed.