Reduction of seed motion using a bio-absorbable polymer coating during permanent prostate brachytherapy using a mick...

Area of Science:

• Oncology
• Medical Physics
• Radiotherapy

Background:

• Low dose rate (LDR) prostate brachytherapy utilizes radioactive seeds for cancer treatment.
• Seed migration can lead to suboptimal radiation delivery and potential complications.
• A bio-absorbable vicryl coating has been developed to enhance seed stability.

Purpose of the Study:

• To evaluate the efficacy of a vicryl coating in preventing seed movement during LDR prostate brachytherapy.
• To compare the incidence and severity of seed slippage between coated and uncoated radioactive seeds.
• To assess the impact of seed coating on initial implant stability.

Main Methods:

• A single-institution study involving 47 patients undergoing LDR prostate brachytherapy.
• Patients received either coated (n=26) or uncoated (n=21) AgX100 125I or uncoated Model 200 103Pd seeds.
• Ultrasound-guided implantation allowed real-time categorization of seed position (in place, moved slightly, or out of view).

Main Results:

• Coated seeds showed a significantly lower incidence of movement (3.1%) compared to uncoated seeds (6.9%), representing a 54.4% reduction (P=0.0026).
• Coated AgX100 seeds had a 66.7% lower movement rate than uncoated AgX100 seeds (P=0.038).
• No significant differences in Day-0 postoperative dosimetric coverage were observed, though further analysis is needed.

Conclusions:

• Vicryl coating significantly reduces the propensity of radioactive seeds to slip from their intended positions.
• This improved stability may help maintain dosimetric integrity in LDR prostate brachytherapy.
• Further investigation into postoperative dosimetry with coated seeds is warranted.