Correlation between radiation dose and tumor recurrence and complications in carcinoma of the uterine cervix: Stages I and IIA

A retrospective analysis is reported on 330 patients with carcinoma of the uterine cervix, 23 with Stage IA, 233 with Stage IB and 74 with Stage IIA disease treated with irradiation alone. The dose of irradiation delivered to the cervix, paracervical tissues or the pelvic lymph nodes was correlated with tumor control. There were no central or parametrial failures in patients with Stage IA disease. There were 4 local or marginal (central) recurrences (1.6%) and 15 (6.5%) parametrial failures in the patients with Stage IB disease. Of 74 patients with Stage IIA disease, 3 developed cervical failures (3.9%) and 4 had both central and parametrial recurrences (5.2%). A definite correlation was found between the dose of irradiation delivered to the pelvic lymph nodes and the incidence of recurrences in the patients with Stage IB disease, (about 20%) parametrial failures with doses below 4000 rad in contrast to about 5% with 4000-5000 rad and 2% with doses over 6000 rad). Among patients with Stages IB and IIA disease, the survival of those who were treated with radiation alone and who received doses less than 4000 rad was about 10% less than patients who were treated with higher doses. This difference is not statistically significant; however, it suggests strongly that higher doses of irradiation to the parametria correlate with better tumor control in the pelvis and survival. Complications were slightly higher with doses to the bladder or rectum over 8000 rad. Although it was not statistically significant, patients who had non-standard intracavitary insertions had approximately 18% complications in contrast to only 6.6% in 135 patients with adequate insertions. Factors other than total dose of irradiation, such as geometry of the pelvis, characteristics of the tumor, position of the applicator, type of applicators used, loading and dose rate are important in evaluating the effects of irradiation in tumor control and complications of carcinoma of the uterine cervix.