Unlike bladder cancer, prostate cancer has highly effective androgen-pathway inhibitors (ARPIs) that extend survival. This success has pushed chemotherapy and, by extension, ADC development to later treatment lines as clinicians prioritize other novel mechanisms of action first.

Shifting the view of prostate cancer from "androgen-driven" to "androgen receptor-driven" provides a new framework. In curative settings, after the androgen receptor is targeted for a defined period, restoring testosterone is seen as logical to improve patient quality of life once the cancer is destroyed.

After years of successfully intensifying hormonal therapy, the focus in prostate cancer is shifting toward de-intensification. Researchers are exploring intermittent therapy for top responders and developing non-hormonal approaches like radioligands to spare patients the chronic, life-altering side effects of permanent castration.

The term "hormone resistance" was misleading. Researchers discovered that even in a castrate state, prostate cancer tumors produce their own testosterone locally. This maintained androgen receptor signaling, proving the disease was still "androgen addicted" and opening the door for new targeted therapies.

The rapid advancement of ARPIs wasn't just a scientific breakthrough. It was a rare convergence of FDA interest in new endpoints, a deeper biological understanding of castration resistance, and intense industry and academic collaboration that created a uniquely fertile ground for innovation.

The NCI Working Group argues against equating PSMA PET-positive biochemically recurrent (BCR) prostate cancer with traditional metastatic disease. They propose the term "PSMA positive BCR" to emphasize that traditional prognostic factors still apply and the natural history is distinct and often more indolent.

New guidelines from an international working group are replacing patient-insensitive terms like "castration-resistant" with "Androgen Pathway Modulator (APM) resistant/naive." This modernizes language to encompass a broader range of therapies and improve patient communication, while also incorporating sensitive imaging like PSMA PET.

The term "APMR" (Androgen Pathway Modulator Resistant) is being adopted over "CRPC." This new terminology is more scientifically accurate for modern hormonal therapies and uses more patient-friendly language by removing the anxiety-inducing word "castration."

PCWG4 replaces terms like "castration-resistant" with "Androgen Pathway Modulation (APM) resistant." This change is driven by patient feedback finding the term "castration" insensitive and by the need for language that reflects modern treatments that don't always involve medical or surgical castration.