Treatment
tumor, CTVp
PRIMARY TUMOR, TUMOR, PROSTATE, DISEASE
The trial schema is given in Fig. 
ROADSTER trial schemaBrachytherapy will be performed using transrectal ultrasound (TRUS) guidance, under general anesthesia in a dedicated brachytherapy suite, with intraoperative planning. Pre-procedure PSMA PET/MR images will be fused with intra-operative TRUS images using an in-house developed surface-based deformable algorithm to accurately delineate the areas of ILF. For each HDR brachytherapy treatment, 10.5 Gy will be prescribed to the entire prostate, with a focal boost to 13.5 Gy to the clinical target volume of the primary tumor (CTVp), as defined by the gross tumor volume (GTV) on all available images with a 5 mm expansion to account for microscopic disease. Details on brachytherapy planning objectives are found in Table 
Dose objectives for a single HDR brachytherapy treatment

Lu-177 PSMA RLT will be delivered in the Department of Nuclear Medicine as per local practice. One dose of 6.8 GBq of Lu-177 PSMA RLT will be administered intravenously, which will deliver an estimated tumor dose of 13.6–40.8 Gy, given the estimated dose of 2–6 Gy per GBq that has been reported in the literature [Figure 
Representative images of the first ROADSTER patient enrolled on cohort 2Figures 
Post Lu-177 PSMA RLT SPECT/CT imagesFigures 