The risk of second primaries subsequent to irradiation for cervix cancer

A review of 1048 patients with cancer of the cervix treated with radiation, either alone or combined with surgery, disclosed 32 cases of second primary malignancies occurring from 1 to 16 years subsequent to treatment. Using the person years approach, the incidence rate of second primaries was 5.49 per 1000 person years, which is not significantly different from population based rates. The anatomic locations of the new malignancies and the times from treatment of the cervix cancer to diagnosis of a new primary are presented; the possible carcinogenic effects of radiation are discussed. In this group of patients, it was concluded that under the period of observation irradiation administered at therapeutic doses did not increase the probability of second malignancy in the pelvis or at other sites.