A quantified approach to the analysis and prevention of urinary complications in radiotherapeutic treatment of cancer of the cervix.

This paper is the report of a dosimetric study of 79 urinary complications after radical radiation treatment (1975-1979) of 624 cervical uterine tumors. Treatment consisted of external irradiation (25 MeV linear accelerator) and intracavitary irradiation (Fletcher-Suit-Delclos applicator). Dosimetric-computerized studies were expressed as the maximum bladder dose on the trigone, as proposed by the I.C.R.U. Bladder doses were actually studied as a function of intracavitary irradiation and intracavitary + external irradiation. The results show a significant difference in patients with and without complications based on the dose reaching the bladder. The relative contribution of external therapy and intracavitary irradiation and their value can serve as one of the primary indicators for predicting complications. These values should be determined before placement of intracavitary sources. We found that the dose to the critical organs cannot be defined as a single number. These results argue in favor of adapting individual patient therapy based on rectal and bladder dosimetry and may be adjustable to all treatment modalities.