What dose-fractionation do you use for salvage HDR brachytherapy for biopsy proven locally recurrent prostate cancer after prior external beam radiotherapy?

I believe most people use 27 Gy in 2 fractions (two insertions spaced by 1-2 weeks) based on a prospective, pilot study from Sunnybrook (NCT01583920; Corkum et al., PMID 35718075). Another dose schedule used by some is 32 Gy in 4 fractions (single insertion, > 4 hrs between fractions over 30 hours) ...

I used 27 Gy in 2 fractions over 2 implants for "focal" salvage. I used to use 36 Gy in 6 fractions over 2 implants for treating the whole gland (Lee et al., PMID 17197119, Chen et al., PMID 23474112, Wu et al., PMID 34077809).