Would you dose escalate for prostate cancer extending to the penile bulb, towards the urethra, and close to anorectal junction?

I agree with Dr. @Dr. First Last's inquiry regarding the definition of "dose escalation" in this setting. In my mind, the question relates not so much to dose as to target coverage. I would not alter dosing on this basis but would carefully assess the appropriate target with pelvic MRI and PSMA PET-CT. In my practice, these have been readily approved with either unfavorable intermediate-risk or high-risk disease. You may already have an MRI given your statement regarding the loss of tissue planes after 3 months of ADT. Moreover, these 3-months of ADT may obscure findings on a new MRI or PSMA PET. PSMA PET can be very interesting in terms of tumor extent and adenopathy, possibly even inguinal adenopathy with his tumor near the anorectal junc...

Dose escalate above what? And is there regional or distant metastatic disease on PSMA PET?

A patient with the extent of disease described is not a good candidate for "focal" boost like FLAME because it isn't focal. The options, then, are escalation of dose to the full prostate via EBRT or brachytherapy. I would be cautious in this situation because of the high chance of distant spread and the high probability of recurrence. I would not generally try to escalate beyond typical EBRT doses. Assuming no metastatic disease, I would include nodal RT. And consider augmenting systemic therapy, depending on PSA and Gleason grade.

I may be reading too far into the question regarding the potential for a single PI-RADS lesion to be in the apex region of the prostate with proximity co-planarly to both the urethra and rectum, and just superior to the penile bulb.

We attempt to 'focally' boost all PI-RADS lesions called on MRI (not our own read, based on our Radiology colleagues' read given Dr. @Dr. First Last's study showing ROs are not good at it: Lui et al., PMID 37453559) that are correlating to areas of positive biopsy, with importance given to prioritize urethral constraints.

I would boost as much of the suspicious area as possible while respecting institutional hard constraints for the urethra, penile bulb, and rectum. While our goal is that 50% of the 'GTV' gets th...