Prostate Cancer
An androgen-driven adenocarcinoma that arises mainly in the peripheral zone of the prostate, away from the urethra, which is why it grows silently for years before causing symptoms and why PSA screening is imperfect.
First principles
Where the cancer arises explains why it is silent for so long
Most prostate cancer arises in the peripheral zone, the part of the gland furthest from the urethra, in contrast to BPH which arises in the periurethral transitional zone. Because the peripheral zone does not encircle the urethra, a tumour can grow substantially there without narrowing the urinary channel or producing lower urinary tract symptoms, which is why early prostate cancer is so often asymptomatic and why symptoms, when they do appear, typically signal locally advanced disease that has grown to involve the urethra, bladder neck or beyond the gland.
Educational content pending clinical review. Not medical advice.