Migration of implanted free radioactive seeds for adenocarcinoma of the prostate using a Mick applicator

This study investigates the rate of free seed migration and associated seed-related sequelae after using a radioimmunoguided Mick applicator technique to place radioactive seeds within the prostate.

Between December 1998 and September 2002, 120 patients diagnosed with prostate cancer underwent interstitial transperineal prostate brachytherapy with free (125)I or (103)Pd seeds positioned using a radioimmunoguided Mick applicator technique. Orthogonal pelvic and chest radiographs were obtained postimplant (Day 0) and at a second follow-up visit to determine the rate of radioactive seed embolization.

On the day of implant (Day 0), 7 (6%) of the 120 men demonstrated single pulmonary seed emboli; none of these seeds migrated subsequently. During follow-up, 87 (72.5%) men had a total of 249 (2.0%) out of 12,524 seeds implanted migrate. Sixty-eight (0.55%) of the implanted seeds migrated to the lungs, an incidence common among brachytherapy techniques utilizing free or vicryl-laden radioactive seeds. No clinical symptoms or adverse sequelae from seed emboli have been reported.

The rate of seed emboli to the pulmonary vessels or to other tissue localities resulting from a radioimmunoguided Mick applicator technique does not appear to be markedly different from the reported rate seen with other free seed techniques.