Impact of suboptimal tandem implantation on local control and complications in intracavitary brachytherapy for cervix cancer.

Suboptimal implantation was frequent. In the absence of image guidance during implantation, conversion to other treatment modalities (including external beam radiation therapy) due to insertion difficulties resulted in worse local control. With optimization, however, suboptimal brachytherapy implantation did not result in suboptimal dose coverage or poorer local control. Failure to perform a brachytherapy boost correlates with increased local failure risk in patients with cervix cancer, whereas tandem malposition does not. Real-time intraoperative ultrasound guidance may be useful to reduce uterine perforation rates and thus increase brachytherapy use.