The use of linked seeds eliminates lung embolization following permanent seed implantation for prostate cancer

A number of reports of (125)I seed migration to the lungs after prostate brachytherapy have been published. There are, however, very limited data available on how to reduce the risk of this event. The purpose of the present report is to determine whether seed embolization to the lungs can be minimized by using stranded seeds alone for brachytherapy.

Between December 2001 and December 2002, 238 patients with early prostate cancer were treated with prostate brachytherapy as monotherapy using (125)I stranded seeds (RAPIDStrand) exclusively. All patients had fluoroscopy during the implant and immediate postimplant radiographs of the pelvis. A sample of 100 patients had chest radiographs performed, on average, 55 days after implant. To determine the ease, or lack of ease, with which these (125)I seeds could be visualized, 4 patients who did not have prostate cancer and who were having routine chest radiographs as part of their management for other cancers consented to have posteroanterior and lateral radiographs performed with inactive (125)I seeds taped to the skin of the thorax. All radiographs were reviewed by a single radiologist.

The number of seeds noted on the postimplant radiographs corresponded to the number of implanted seeds in all 238 cases: There was, therefore, no evidence of seed embolization immediately postimplant. On review of the 100 chest radiographs, no embolized seeds were found.

No evidence of seed embolization was observed with the use of stranded (125)I seeds as used for prostate brachytherapy.