Prostate Cancer — Causes, Symptoms, PSA Screening & Treatment Guide — Symptoms, Causes & Treatment | MyMedicPlus

Prostate cancer is a malignant tumour arising from the glandular epithelium of the prostate gland, located below the bladder and surrounding the urethra. It is the second most common cancer in men globally (after lung cancer) and the most common cancer in men in the UK and USA, with approximately 1.4 million new cases and 375,000 deaths annually worldwide. The majority of prostate cancers are adenocarcinomas (over 95%), with the posterior peripheral zone most commonly affected. Prostate cancer is clinically heterogeneous, ranging from slow-growing, low-risk cancers that may never cause symptoms or shorten life (present in up to 50% of men over 80 at autopsy) to aggressive, metastatic cancers requiring immediate treatment. Risk stratification using PSA level, Gleason score (now Grade Group 1-5), TNM stage, and MRI findings guides treatment decision-making between active surveillance, curative treatment, or palliative systemic therapy. The 5-year survival for localised prostate cancer exceeds 99% in the UK and USA; for metastatic disease, it remains approximately 30-40% (but is improving with new drug approvals).

Prostate cancer risk increases markedly with age — over 75% of cases are diagnosed in men over 65. Race/ethnicity: Black/African American men have significantly higher incidence (1.7x) and mortality (2.1x) than white men; Asian men have the lowest incidence globally, though risk increases with westernisation. Family history: first-degree relative with prostate cancer doubles the risk; 2+ first-degree relatives increases risk 5-11x. Hereditary prostate cancer: BRCA2 germline mutation confers 5-8x increased risk of aggressive prostate cancer and is found in 2-5% of unselected cases; BRCA1, ATM, CHEK2, and Lynch syndrome (MLH1, MSH2) also increase risk. High testosterone levels and androgenic signalling drive prostate cancer growth — hence androgen deprivation therapy (ADT) is central to advanced disease treatment. Lifestyle factors with modest associations: high red meat and dairy consumption, obesity, and lack of physical activity. Protective factors: lycopene (from tomatoes), omega-3 fatty acids, and statins (emerging evidence — associations not causal).

Early localised prostate cancer is frequently asymptomatic — discovered only through PSA testing. When symptoms occur with localised disease, they typically reflect bladder outflow obstruction (lower urinary tract symptoms/LUTS) — similar to benign prostatic hyperplasia (BPH): increased urinary frequency, nocturia, hesitancy (difficulty starting urination), poor stream, terminal dribbling, and incomplete bladder emptying. Blood in urine (haematuria) or semen (haematospermia). Locally advanced cancer (extending beyond the prostate capsule or invading seminal vesicles): worsening LUTS, haematuria, and — if rectal invasion — change in bowel habit. Metastatic prostate cancer (most commonly spreads to bone): bone pain — particularly in the lumbar spine, pelvis, hips, and femur — which may be the first presentation; spinal cord compression (back pain with bilateral leg weakness, sensory disturbance, and urinary/bowel dysfunction — a medical emergency requiring urgent MRI); lymph node enlargement; constitutional symptoms (weight loss, fatigue, anaemia from marrow infiltration).

PSA (prostate-specific antigen): a serine protease produced exclusively by prostate epithelium. Elevated PSA (above 4 ng/mL — threshold varies by age, ethnicity, and prostate volume) triggers further investigation. PSA density (PSA/prostate volume) and PSA velocity (rate of rise) improve specificity. PSA is not cancer-specific — also elevated in benign prostatic hyperplasia (BPH), prostatitis, and post-catheterisation. MRI of the prostate (mpMRI — multi-parametric MRI): now recommended before biopsy in most guidelines; characterises lesion location, size, and PI-RADS score (1-5) — PI-RADS 4-5 lesions are highly suspicious. Fusion-targeted biopsy (MRI-targeted + systematic transperineal biopsy): superior to systematic transrectal biopsy for detecting clinically significant cancer while reducing detection of insignificant low-grade disease. Histopathology: Gleason score (2-10) and Grade Group (1-5) characterise tumour aggressiveness. TNM staging: extent of local disease (T stage), lymph node involvement (N stage), and distant metastasis (M stage). Staging investigations for intermediate/high-risk disease: pelvic MRI, bone scan, CT chest/abdomen/pelvis, or next-generation imaging (PSMA-PET/CT — highly sensitive for nodal and distant metastases). Germline genetic testing (BRCA1/2, ATM) for all men with metastatic prostate cancer and high-risk localised disease.

Low-risk localised prostate cancer (Grade Group 1 — Gleason 3+3): active surveillance — PSA monitoring every 3-6 months, repeat MRI, and repeat biopsy (1-3 years) — avoids overtreatment of indolent cancers; approximately 50% of patients remain on surveillance without needing treatment for 10+ years. Intermediate and high-risk localised prostate cancer: radical prostatectomy (open or robot-assisted laparoscopic — RARP) removes the entire prostate; external beam radiotherapy (EBRT) — 20 fractions stereotactic body radiotherapy (SBRT) or intensity-modulated radiotherapy (IMRT) — with 6 months neoadjuvant ADT for intermediate-risk, 2-3 years for high-risk. Brachytherapy (radioactive seed implants) for selected patients. Locally advanced (non-metastatic, high-risk): radiotherapy + long-term ADT (2-3 years); enzalutamide (ENZAMET, ARCHES trials) or apalutamide (TITAN trial) added to ADT in castration-sensitive metastatic disease prolongs survival. Metastatic castration-sensitive prostate cancer (mCSPC): ADT + docetaxel chemotherapy (for high-volume/high-risk); or ADT + novel hormonal agent (abiraterone/enzalutamide/apalutamide/darolutamide); or ADT + docetaxel + novel hormonal agent (PEACE-1, ARASENS trials — greatest survival benefit in high-volume disease). Metastatic castration-resistant prostate cancer (mCRPC): enzalutamide, abiraterone, docetaxel, cabazitaxel; PARP inhibitors (olaparib, rucaparib) for BRCA1/2-mutated mCRPC; 177Lu-PSMA-617 (Pluvicto) for PSMA-positive mCRPC post-docetaxel. Spinal cord compression: dexamethasone 16 mg/day STAT + urgent radiotherapy or neurosurgery.

Metastatic prostate cancer causes severe complications from both the disease and its treatments. Bone metastases — present in 90% of metastatic prostate cancer cases — cause severe bone pain (especially in the spine, pelvis, and femur), pathological fractures, and spinal cord compression (cauda equina syndrome — a urological emergency presenting with leg weakness, saddle anaesthesia, and urinary or faecal incontinence requiring emergency MRI and surgical decompression or radiotherapy within hours). Castration-resistant prostate cancer (CRPC — progressing despite castrate testosterone levels below 1.7 nmol/L) is treated with abiraterone (CYP17A1 inhibitor blocking adrenal androgen synthesis) or enzalutamide (androgen receptor antagonist), but carries median survival of 24-36 months. Treatment-related complications are substantial: radical prostatectomy causes urinary incontinence (10-20% requiring pads at 12 months) and erectile dysfunction (40-80% depending on nerve-sparing technique). External beam radiotherapy causes radiation cystitis, proctitis, and delayed urethral stricture. Androgen deprivation therapy (ADT) — via LHRH agonists (leuprolide, goserelin) or LHRH antagonists (degarelix) — causes hot flushes (affecting 80%), osteoporosis (bone density declining 2-7% annually — zoledronic acid or denosumab prophylaxis recommended), anaemia, metabolic syndrome, cardiovascular disease, depression, and cognitive impairment with prolonged use.

No proven dietary or lifestyle intervention definitively prevents prostate cancer. Maintain healthy weight — obesity is associated with higher risk of aggressive prostate cancer and poorer outcomes. Regular exercise reduces prostate cancer risk modestly. PSA screening remains controversial: the USPSTF and NICE do not recommend universal PSA screening for all men due to overdiagnosis and overtreatment of indolent cancers. Informed decision-making about PSA testing is recommended: men aged 50-69 with average risk should discuss the benefits and harms with their doctor; men at higher risk (Black men from age 45, positive family history from age 40, BRCA2 carriers from age 40) should be offered earlier informed discussion. BRCA2 carriers have the highest individualised benefit from prostate cancer screening. Germline testing for high-risk prostate cancer families enables cascade testing of sons and brothers, who can make informed choices about surveillance.

See your GP urgently for: lower urinary tract symptoms (hesitancy, poor stream, frequency, nocturia) that are worsening or associated with blood in urine; unexplained bone pain in the spine, pelvis, or hips in a man over 50; unexpected weight loss with fatigue. Emergency 999/911 for: sudden loss of power or sensation in both legs, inability to walk, or loss of bladder/bowel control in a man with known prostate cancer (possible spinal cord compression — a neurosurgical emergency requiring emergency MRI and dexamethasone within minutes). Men with a father or brother who had prostate cancer under 60 should discuss PSA testing with their GP from age 40-45. Black men have significantly higher risk and should seek discussion with their GP about PSA testing from age 45.