How do you sequence HDR brachytherapy boost and external beam RT for prostate cancer?

The typical sequence for our combination IMRT/HDR patients is IMRT first followed by the HDR boost about a week later. HDR is much more forgiving (substantially less GU toxicity) so the gap between IMRT and HDR is less than when we did seed boosts. However, our first clinical trials in the late 1990...

I think either approach is acceptable.

The THEPCA study has been presented in abstract form: https://ascopubs.org/doi/abs/10.1200/JCO.2021.39.6_suppl.236.

Patients randomized to HDR boost either prior or after EBRT.

No sig diff in GI/GU toxicities at 1 year.

Will be nice to see the THEPCA study publis...