Poster Presentation – Abstracts Archive
UK & Ireland Prostate Brachytherapy Conference 2013
Abstract number 12
A Report on the Initial Experience of the BARD ‘Prolink Brachytherapy System’ in the Treatment of early stage Prostate Cancer
S Thompson
Radiotherapy Physics, University Hospital Southampton NHS Foundation Trust
J Nevinson
Radiotherapy Physics, University Hospital Southampton NHS Foundation Trust
Aims/Introduction: Practical implementation and initial experience of the Bard One-Step Interoperative Prolink technique at University Hospital Southampton NHS Foundation Trust (UHS); first UK hospital to adopt this technique is described. Key objectives for a streamlined fully dynamic one-step permanent prostate implant: utilising non-uniform seed spacing, reducing implant needle number, providing good visibility on ultrasound imaging and enabling precise seed drop screen-capture.
It is a requirement to independently perform a seed assay of at least 10%(1,2) prior to clinical use of I125 seeds. Measuring seed activity whilst maintaining sterility is a Prolink Seed Cartridge Assay difficulty.
Both implant process and current seed assay techniques are examined.
Materials/Methods: 33 patients with prostate gland sizes of no greater than 50 cc were implanted using linked seed technique; non-uniformly spaced predominantly peripherally loaded STM1251 seeds. Planned needle number used has been compared with that of similar volume plans, from our previous uniformly spaced seed implant series.
Pre-implant dual method seed assay is performed: i) 5 evenly spaced linked seedtrain, with calibration route traceable to National Dosimetry Standard, and ii) Intact multi-seed cartridges within improvised sterile pouches, for which factors correcting for geometry & self-absorption(3) , are calculated from single seed versus intact cartridge measurement.
Results: UHS Prolink plan analysis shows a 27% reduction in needle number. This fits with the previously described 30% reduction(4) (compared with fixed interseed spacing).
Corrective factors ranging from 1.12 to 1.22 depending on seed number per cartridge, give assay tolerance within 5%, compared to 3% for the 5 linked seed strand.
Conclusions: Adopting Bard Prolink technique has improved UHS Prostate Brachytherapy service, met key objectives with fewer needles required, reduced likelihood / severity of oedema, without compromising prostate dose, and shortened procedure duration. Accessory refinement will increase accuracy of intact cartridge whole seed batch assay and further service streamlining.
References
- The Royal College of Radiologists. Quality assurance practice guidelines for transperineal LDR permanent seed brachytherapy of prostate cancer. London: The Royal College of Radiologists, 2012.
- Butler WM, Bice WS Jr, DeWerd LA et al. Med Phy 2008; 35(9): 3860-3865
- Mellenberg, DE Jr, Kline RW. Med Phys 1995; 22(9): 1495-1497
- Steggerda MJ, van der Poel HG, Moonen LM. Brachytherapy 2010; 9(4): 319-327