Prognostic assessment of tumor regression after external irradiation for cervical cancer

From February 1980 to December 1986, 428 cases of cervical cancer in Stage I through IVA were given curative radiation therapy at Chang Gung Memorial Hospital, Taipei. All of them received external irradiation and intracavitary brachytherapy. The degree of tumor regression was assessed immediately before the first intracavitary brachytherapy treatment. Patients were classified at this time as having (a) no gross residual tumor, or (b) gross residual tumor. Factors found to be associated with tumor regression by logistic regression analysis were stage, age and hemoglobin level. Patients with advanced cancer (Stage III, IVA), young age (<40 years), and low hemoglobin level (<10 g/dl) had a low incidence of no gross residual tumor. Five-year survival rate was 77% in patients with no gross residual tumor and 31% in patients with gross residual tumor (p < 0.001). This significant difference held true even when one compared these two groups stage for stage; the difference was 77% versus 41% (p < 0.001) in Stage II and 72% versus 28% (p < 0.001) in Stage III. The local relapse rate was 59% in the gross residual tumor groups, significantly greater (p < 0.001) than the 12% found in the no gross residual tumor group. It was concluded that patients whose tumors did not regress after external pelvic irradiation tended to recur after intracavitary brachytherapy, most often locally. This would justify a more aggressive treatment to improve local tumor control in this subset of high risk patients.