Deformable Registration of Multi-parametric MRI to Intra-operative Transrectal Ultrasound for Prostate Brachytherapy

Prostate Cancer

Image guided brachytherapy

Objective: To focus the high dose radiation to the gross tumor in the prostate while maintaining adequate dose for control of microscopic disease elsewhere in the prostate. In order to test the incorporation of the robust MRI and TRUS fusion algorithm in the clinical setting the investigators planned a study of Focused therapy with a primary endpoint of accurate localization of the high risk region. This is a pilot study of dose painted permanent I-125 seed implant to verify absence of tumor cells outside a high risk region using multi-parametric MRI and deformable TRUS registration. The high risk region will be dose painted to 160 Gy and the rest of the prostate will receive the normal prescription dose.

Primary end-point: Feasibility of dose painting will be determined by the absence of tumor outside the high-risk region on an intra-operative trans-perineal biopsy. Frozen sections will not be obtained, however on receipt of the final pathology 2-4 weeks after the procedure 2 possible scenarios arise: 1. There is no evidence of cancer: this confirms the accuracy of the TRUS MRI registration. 2. There is evidence of tumor on the stereotactic biopsy: In this case a regular dosimetric check (this is performed in the Standard of care procedure and is known as post-operative dosimetry) will be performed to determine whether adequate dose was delivered. If not, as the involved needle position was recorded in the treatment plan and labeled with co-ordinates, the regular possibility of accurately adding radioactive seeds is possible.

No related papers found yet.

Israel