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Updated: Jul 19, 2026
A New Technique for Treating Low-risk Prostate Cancer—Super Active Surveillance
Published on: November 7, 2025
Permanent prostate implant using high activity seeds and inverse planning with fast simulated annealing algorithm: A
André-Guy Martin1, Jean Roy, Luc Beaulieu
1Département de Radio-oncologie, Centre de Recherche en Cancérologie de l'Université Laval, Québec, Canada.
Purpose:
To report outcomes and toxicity of the first Canadian permanent prostate implant program.
Methods And Materials:
396 consecutive patients (Gleason < or =6, initial prostate specific antigen (PSA) < or =10 and stage T1-T2a disease) were implanted between June 1994 and December 2001. The median follow-up is of 60 months (maximum, 136 months). All patients were planned with fast-simulated annealing inverse planning algorithm with high activity seeds ([gt] 0.76 U). Acute and late toxicity is reported for the first 213 patients using a modified RTOG toxicity scale. The Kaplan-Meier biochemical failure-free survival (bFFS) is reported according to the ASTRO and Houston definitions.
Results:
The bFFS at 60 months was of 88.5% (90.5%) according to the ASTRO (Houston) definition and, of 91.4% (94.6%) in the low risk group (initial PSA < or =10 and Gleason < or =6 and Stage < or =T2a). Risk factors statistically associated with bFFS were: initial PSA >10, a Gleason score of 7-8, and stage T2b-T3. The mean D90 was of 151 +/- 36.1 Gy. The mean V100 was of 85.4 +/- 8.5% with a mean V150 of 60.1 +/- 12.3%. Overall, the implants were well tolerated. In the first 6 months, 31.5% of the patients were free of genitourinary symptoms (GUs), 12.7% had Grade 3 GUs; 91.6% were free of gastrointestinal symptoms (GIs). After 6 months, 54.0% were GUs free, 1.4% had Grade 3 GUs; 95.8% were GIs free.
Conclusion:
The inverse planning with fast simulated annealing and high activity seeds gives a 5-year bFFS, which is comparable with the best published series with a low toxicity profile.
