What is your preferred dose to gross lymph nodes when treating non-metastatic high-risk prostate cancer?

I treat the grossly involved node as high as I can, while respecting OAR constraints, up to the dose for the prostate. I tend to favor zero or minimal PTV margin (depending on the proximity of OARs--usually bowel) and allow the penumbra to serve as a functional "PTV."

We treat in 28 fractions and I most commonly aim for 63 Gy to involved nodes, but may have to reduce to 60 Gy (sometimes less) in order to keep small bowel max <54. It depends on the location, obturator nodes can be pretty isolated so might get 70 Gy without issue, low internal iliacs increase the rectal dose, low external iliacs can affect the bladder, and higher nodes get closer to bowel. I try to avoid much increase in OAR exposure since the DM rate is expected to be high, and with the same r...

I agree with Drs. @Dr. First Last and @Dr. First Last. I'll try to get as close to the prostate dose as I can without exceeding OAR tolerance. I think 2 points are worth emphasizing. First, the pattern of failure in these patients is predominantly distant, so I think you should prioritize OAR (i.e., bowel) protection over nodal target coverage. Second, the planning scan is a snapshot in time and probably does not well represent day-to-day mobile bowel positioning relative to the target. Thus, do...

In the STORM study, it was up to 65 Gy in 25 fractions (GTV plus 5 mm) based on OAR and reported excellent index nodal control.

Usually 66 Gy/33 fractions to avoid small bowel injury.

While the Gyn literature is more extensive, the prostate nodal literature is relatively sparse. The Gyn data suggests as high as you can go for boost, but also showed that perhaps little is gained from elective dosing 50.4 compared to 45 Gy (apart from added toxicity).

Francolini's paper from 2022 is the largest I know of (PMID 34850352) that looks at dosing and patterns of failure after fractionated ENI + boost to prostate nodes. They did show worse bRFS with <60 Gy boost to involved LN using a...

Case specific. 59.4-66 in std fractionation in general. (I often do hypo and SBRT in these cases). However, there are reasons I would go lower or higher based on the therapeutic ratio.

If the therapeutic ratio is high such as low volume nodes confined to the “pelvis” seen only on PET with a controllable primary in a healthy patient then I would potentially go higher than 66 depending on location (beware the sacral plexus).

If the therapeutic ratio is low such as massive nodes, enormous advanced...