Oral and Poster Prestentation – Clinical Abstracts Archive

UK & Ireland Prostate Brachytherapy Conference 2017

Abstract number 2

Focal salvage LDR brachytherapy for prostate cancer – Edinburgh Cancer Centre experience

Lee J*; McLaren D*; Keough W*
*Edinburgh Cancer Centre

In the ECC, we treat around 80 patients per year for early to intermediate stage prostate cancer using LDR brachytherapy. Focal salvage brachytherapy has the potential to be an effective treatment for local recurrence with no metastases. Since 2015, we have identifi ed 7 patients, with local recurrence, that were good candidates for focal salvage brachytherapy. Patients presented with slow rise in PSA during follow up on average 9 years post initial treatment. Tumour volume was mapped via template biopsy using pre biopsy choline PET and then fused with their post implant CT scan to determine if there was a treatment miss in the fi rst instance and to assess dose coverage to recurrent tumour. Tumour recurrence position varied. Common areas of recurrence were found in the base of the prosate and one patient had localised disease in the seminal vesicles. Only one patient had bi-lateral disease and this was treated accordingly. Mean number of seeds and needles used was 27 and 12, respectively. Treatment was planned using 2 step process. The PTV was outlined by the radiologist and oncologist based on the pathology results and choline PET scan allowing the planner to optimise dose to this area with a margin (CTV+5mm). Prescribed dose was 145Gy to PTV. Mean planned V100 to PTV was 98.9% and D90 was 162.3%. Considerations taken into account when planning included attenuation from previous I-125 seeds and any calcifi cations identifi ed since EBRT. Patients attended follow up (3monthly clinic review) and a post implant CT scan was carried
out and results were identifi ed from EBRT group. All patients are doing well, with some toxicity including rectal dysfunction and nocturia. PSA levels have dropped and stabilised in all patients treated (IPSS and PSA results available). Focal salvage therapy has proven to be a successful treatment within the ECC.