Prostate Cancer

Most prostate cancers are adenocarcinomas arising from glandular epithelial cells. Many begin in the peripheral zone, which lies away from the urethra. A tumour can therefore grow for some time without narrowing the urinary channel, so early prostate cancer is often asymptomatic. Growth is usually stimulated by androgen signalling, particularly testosterone and dihydrotestosterone acting through the androgen receptor. This biology explains why androgen-deprivation therapy (ADT) is effective against metastatic disease: it reduces the hormonal stimulation that prostate cancer cells use to grow. Cancer may remain confined to the prostate or extend into nearby structures and lymph nodes. Distant spread commonly involves bone, where it can cause persistent back, hip, or pelvic pain, reduced mobility, pathological fracture, or—if the spine is involved—spinal cord compression. Advanced disease may also produce fatigue, weight loss, anaemia, or urinary obstruction. Benign prostatic hyperplasia (BPH) is a frequent look-alike. BPH usually enlarges tissue around the urethra and commonly causes hesitancy, a weak stream, frequency, and nocturia. Those symptoms do not distinguish BPH from cancer, and the two conditions can occur together. Conversely, the absence of urinary...