Iodine-125 thin seeds decrease prostate swelling during transperineal interstitial permanent prostate brachytherapy.

Area of Science:

• Urology
• Oncology
• Medical Physics

Background:

• Prostate swelling is a common occurrence after seed implantation for brachytherapy.
• Understanding and mitigating post-implant swelling is crucial for treatment efficacy and patient comfort.

Purpose of the Study:

• To evaluate if using thinner seeds in permanent prostate brachytherapy can reduce post-implant swelling.
• To compare outcomes of thin seeds versus standard seeds in terms of swelling, operative time, and toxicity.

Main Methods:

• Eighteen patients underwent prostate seed implantation using iodine-125 (I-125) thin seeds.
• Data on operative time, dosimetry, prostate swelling, and toxicity were collected.
• These metrics were compared against a control group using standard I-125 stranded seeds.

Main Results:

• Thin seeds led to a significant reduction in prostate volumes by Day 30 post-implantation (40.9 cc vs. 46.8 cc).
• A learning curve was observed, resulting in longer operative times with thin seeds.
• No significant differences were found in post-implant dosimetry, acute urinary morbidity, or quality of life.

Conclusions:

• Iodine-125 thin seeds effectively reduce early post-implant prostate swelling.
• This reduction has positive implications for optimizing early dose coverage and improving dosimetric assessment accuracy.
• An initial learning curve and increased operative time are associated with thin seed utilization.