Prostate Cancer

Prostate cancer is the most common cancer in UK men, with incidence rising significantly with age. It's more prevalent in Black African-Caribbean men and those with a strong family history (e.g., BRCA2 mutations). Most are slow-growing adenocarcinomas, typically arising in the peripheral zone (70%), unlike BPH which affects the central zone. This peripheral location means it's often asymptomatic until advanced, or detected incidentally. The UK doesn't have a national screening programme, but men over 50 can request an 'informed choice' PSA test. NICE guidelines now recommend multi-parametric MRI (mpMRI) as the initial investigation for suspected prostate cancer, *before* biopsy. Treatment decisions are guided by Gleason Score (histological grading) and TNM staging. For low-risk, localised disease, 'Active Surveillance' is often preferred to minimise treatment side effects, while higher-risk disease requires more aggressive intervention.

Prostate cancer growth is primarily driven by androgens (testosterone and dihydrotestosterone, DHT). Over time, some cancers become 'castration-resistant,' meaning they can grow despite very low androgen levels. The Gleason grading system is crucial for prognosis: a pathologist assigns two grades (1-5) based on the most and second most prevalent architectural patterns in the biopsy. A Gleason score of 6 (3+3) is low grade, 7 (3+4 or 4+3) is intermediate, and 8-10 is high grade. Spread occurs via direct invasion (seminal vesicles, bladder neck), lymphatic spread (obturator, internal/external iliac nodes), and haematogenous spread, with a strong predilection for the axial skeleton (spine, pelvis, ribs) causing osteoblastic (sclerotic) lesions.

Early prostate cancer is usually asymptomatic. Lower Urinary Tract Symptoms (LUTS) are more commonly due to co-existing BPH, but advanced cancer can cause obstruction. Red flag symptoms include new-onset bone pain (especially back pain), unexplained weight loss, or anaemia, suggesting metastatic disease. On Digital Rectal Examination (DRE), a suspicious prostate feels hard, nodular, asymmetrical, or has a lost median sulcus. Complications include spinal cord compression (an oncological emergency requiring urgent MRI and steroids) and obstructive uropathy. Treatment complications are significant: erectile dysfunction and urinary incontinence post-prostatectomy, or radiation proctitis/cystitis post-radiotherapy.

Bedside: Digital Rectal Examination (DRE) – assess size, consistency, symmetry, and presence of nodules. Bloods: Prostate Specific Antigen (PSA) – interpret with age-adjusted thresholds (e.g., >3.0 ng/ml for 50-69 years). Be aware of factors causing false elevation (UTI, vigorous exercise, recent ejaculation, DRE/catheterisation – re-test after 4-6 weeks if these apply). Imaging: Multi-parametric MRI (mpMRI) Pelvis is now standard *before* biopsy. It's reported using a PIRADS or Likert scale (1-5); scores of 3 or more are suspicious. Specialty: Transperineal (TP) biopsy is increasingly preferred over transrectal (TRUS) biopsy due to lower infection risk. For staging: Bone scan (Technetium-99m) and/or CT Abdomen/Pelvis if metastasis is suspected based on PSA, Gleason score, or symptoms.

Management is risk-stratified:
- **Localised Disease (Low risk):** Active Surveillance (regular PSA, repeat mpMRI/biopsies) or Watchful Waiting (for those with limited life expectancy, focusing on symptom control).
- **Localised/Locally Advanced (Intermediate/High risk):** Radical Prostatectomy (surgical removal of prostate and seminal vesicles) or Radical Radiotherapy (External Beam Radiotherapy or Brachytherapy). Hormone therapy is often an adjunct to radiotherapy.
- **Metastatic Disease:** Androgen Deprivation Therapy (ADT) is the mainstay. This involves GnRH agonists (e.g., Goserelin – requires 'flare' protection with an anti-androgen like Cyproterone for the first few weeks) or GnRH antagonists (e.g., Degarelix). Chemotherapy (e.g., Docetaxel) is used in metastatic hormone-sensitive or castration-resistant cases. Bone health is managed with bisphosphonates or Denosumab to prevent skeletal-related events.