Overview
Prostate cancer is one of the most common types of cancer in men, developing in the prostate gland — a small walnut-shaped gland that produces seminal fluid. While some types of prostate cancer grow slowly and may need minimal or no treatment, other types are aggressive and can spread quickly.
The prostate gland is located below the bladder and in front of the rectum, surrounding the upper part of the urethra (the tube that carries urine from the bladder). As men age, the prostate can develop various problems, including benign enlargement (BPH) and cancer. Prostate cancer typically affects men over 50, with the average age at diagnosis being 66 years.
What makes prostate cancer unique is its often slow growth rate. Many men with prostate cancer, especially older men, may never experience symptoms or require treatment. However, some forms can be aggressive and life-threatening, making appropriate screening and risk assessment crucial. The introduction of PSA (prostate-specific antigen) testing has revolutionized early detection, though its use remains somewhat controversial due to concerns about overdiagnosis and overtreatment.
With advances in detection and treatment, the 5-year survival rate for all stages of prostate cancer combined is nearly 100%. For localized and regional prostate cancer, the 5-year survival rate is nearly 100%, while for distant-stage disease, it's about 31%. These statistics underscore the importance of early detection and appropriate management.
Symptoms
Early prostate cancer usually causes no symptoms. When symptoms do occur, they often relate to urinary function or, in advanced cases, to the cancer's spread to other parts of the body.
Urinary Symptoms
Difficulty starting urination, weak or interrupted urine flow, frequent urination (especially at night), urgency to urinate, or inability to empty the bladder completely.
Blood in Urine or Semen
Hematuria (blood in urine) or hematospermia (blood in semen) can occur, though these are less common symptoms.
Erectile Dysfunction
New-onset erectile dysfunction can sometimes be a sign of prostate cancer, especially if accompanied by other symptoms.
Pelvic Discomfort
Pain or discomfort in the pelvic area, lower back, hips, or upper thighs may occur, especially if cancer has spread.
Bone Pain
In advanced cases, when cancer spreads to bones, persistent pain in the spine, ribs, or hips may develop.
Unexplained Weight Loss
Unintentional weight loss and fatigue can occur with advanced prostate cancer.
Important Considerations
- Many of these symptoms are more commonly caused by benign prostatic hyperplasia (BPH) or prostatitis
- Early-stage prostate cancer rarely causes symptoms
- Symptoms typically appear when the tumor is large enough to press on the urethra
- Advanced symptoms suggest cancer has spread beyond the prostate
Note: These symptoms can be caused by conditions other than prostate cancer. However, any persistent urinary symptoms or pelvic discomfort should be evaluated by a healthcare provider.
Causes
The exact cause of prostate cancer isn't fully understood, but it begins when cells in the prostate develop mutations in their DNA. These mutations cause cells to grow and divide more rapidly than normal cells.
Cellular Changes
Prostate cancer develops through a series of genetic changes:
- DNA mutations: Changes in oncogenes and tumor suppressor genes lead to uncontrolled cell growth
- Androgen influence: Male hormones (androgens) like testosterone fuel prostate cancer growth
- Inflammation: Chronic inflammation may contribute to DNA damage
- Oxidative stress: Free radical damage may play a role in cancer development
Key Genetic Alterations
Common genetic changes in prostate cancer include:
- TMPRSS2-ERG fusion: Found in about 50% of prostate cancers
- PTEN loss: Common in advanced prostate cancer
- TP53 mutations: Associated with aggressive disease
- AR amplification: Occurs in hormone-resistant cancers
- BRCA2 mutations: Increase risk and aggressiveness
Contributing Factors
Several factors may contribute to prostate cancer development:
- Age-related cellular changes
- Hormonal influences throughout life
- Dietary factors (high-fat diet, low vegetable intake)
- Environmental exposures
- Chronic inflammation or infection
Risk Factors
Several factors can increase a man's risk of developing prostate cancer. Understanding these risks helps inform screening decisions and prevention strategies.
Non-modifiable Risk Factors
- Age: Risk increases significantly after age 50; rare before 40
- Race/Ethnicity: African American men have highest risk and more aggressive disease
- Family history: Risk doubles with one affected first-degree relative
- Genetic mutations: BRCA1/2, Lynch syndrome genes increase risk
- Geography: More common in North America, Europe, Australia
Potentially Modifiable Risk Factors
- Diet: High-fat diet, especially animal fats, may increase risk
- Obesity: Associated with more aggressive cancers
- Smoking: May increase risk of aggressive prostate cancer
- Chemical exposures: Agent Orange, certain occupational chemicals
- Inflammation: Prostatitis may slightly increase risk
- Vasectomy: Possible slight increase in risk (controversial)
Genetic Risk Factors
Inherited genetic mutations that increase prostate cancer risk:
- BRCA2: 5-7 times increased risk, more aggressive disease
- BRCA1: Moderately increased risk
- HOXB13: Rare mutation with significant risk increase
- Lynch syndrome genes: MSH2, MLH1, MSH6, PMS2
- ATM: Associated with aggressive disease
Screening
Prostate cancer screening remains controversial due to concerns about overdiagnosis and overtreatment. Current guidelines emphasize shared decision-making between patients and providers.
Screening Methods
- PSA blood test: Measures prostate-specific antigen levels
- Normal PSA: Generally <4 ng/mL (varies by age)
- Elevated PSA doesn't always mean cancer
- Some cancers occur with normal PSA
- Digital rectal exam (DRE): Physical examination of the prostate
- PSA derivatives: Free PSA, PSA velocity, PSA density
- New biomarkers: 4Kscore, PHI, PCA3, SelectMDx
Screening Guidelines
Major organizations have different recommendations:
- American Cancer Society: Discuss screening at:
- Age 50 for average-risk men
- Age 45 for high-risk men (African Americans, family history)
- Age 40 for very high risk (multiple family members affected)
- USPSTF: Shared decision-making for men 55-69; generally not recommended after 70
- American Urological Association: Shared decision-making starting at age 55 for average risk
Factors to Consider
- Life expectancy (screening most beneficial if >10 years)
- Personal values regarding risks and benefits
- Risk factors for aggressive disease
- Baseline PSA level
Diagnosis
If screening tests suggest prostate cancer, additional tests are needed to confirm the diagnosis and determine the cancer's characteristics.
Diagnostic Tests
- Multiparametric MRI (mpMRI):
- Increasingly used before biopsy
- Helps identify suspicious areas
- PI-RADS scoring system
- Prostate biopsy:
- Transrectal ultrasound-guided (TRUS) biopsy
- MRI-fusion biopsy
- Transperineal biopsy
- Typically 12-14 core samples
- Pathology analysis:
- Gleason score/Grade Group
- Percentage of cores positive
- Perineural invasion
Additional Testing
For confirmed cancer, staging tests may include:
- Bone scan: Detects bone metastases
- CT scan: Evaluates lymph nodes and organs
- PSMA PET scan: Highly sensitive for detecting metastases
- Genomic testing: Oncotype DX, Prolaris, Decipher
Active Surveillance Criteria
For low-risk cancers, active surveillance may be appropriate:
- Gleason score 6 (Grade Group 1)
- PSA <10 ng/mL
- Clinical stage T1-T2a
- Limited tumor volume on biopsy
Staging & Grading
Accurate staging and grading are essential for treatment planning and prognosis.
TNM Staging
- T (Tumor):
- T1: Tumor not palpable or visible on imaging
- T2: Tumor confined within prostate
- T3: Tumor extends through prostate capsule
- T4: Tumor invades adjacent structures
- N (Nodes): N0 (no spread) or N1 (regional lymph node involvement)
- M (Metastasis): M0 (no distant spread) or M1 (distant metastasis)
Stage Groupings
- Stage I
- T1-T2a, N0, M0, Gleason score ≤6, PSA <10
- Stage II
- T2b-T2c or higher Gleason score/PSA, confined to prostate
- Stage III
- T3-T4 or any T with N1, no distant metastases
- Stage IV
- Any T, any N, M1 (distant metastases)
Gleason Score/Grade Groups
- Grade Group 1
- Gleason score 6 (3+3) - Well differentiated
- Grade Group 2
- Gleason score 7 (3+4) - Moderately differentiated
- Grade Group 3
- Gleason score 7 (4+3) - Moderately differentiated
- Grade Group 4
- Gleason score 8 - Poorly differentiated
- Grade Group 5
- Gleason score 9-10 - Poorly differentiated/undifferentiated
Risk Stratification
- Low risk: T1-T2a, Gleason ≤6, PSA <10
- Intermediate risk: T2b-T2c or Gleason 7 or PSA 10-20
- High risk: T3a or Gleason 8-10 or PSA >20
- Very high risk: T3b-T4 or primary Gleason 5 or >4 cores with Gleason 8-10
Treatment Options
Treatment depends on cancer stage, grade, patient age, overall health, and personal preferences. Options range from active surveillance to aggressive multimodal therapy.
Active Surveillance
For low-risk cancer in men with life expectancy <10-15 years:
- Regular PSA tests (every 3-6 months)
- Annual or biannual prostate biopsies
- MRI monitoring
- Treatment if progression occurs
Surgery
Radiation Therapy
Systemic Therapies
- Hormone therapy (ADT):
- LHRH agonists/antagonists
- Anti-androgens
- Combined androgen blockade
- Chemotherapy: Docetaxel, cabazitaxel for advanced disease
- Novel hormone agents: Enzalutamide, apalutamide, darolutamide, abiraterone
- Immunotherapy: Sipuleucel-T (Provenge)
- Targeted therapy: PARP inhibitors for BRCA mutations
- Radiopharmaceuticals: Radium-223 for bone metastases
Focal Therapies
Emerging treatments for localized disease:
- High-intensity focused ultrasound (HIFU)
- Cryotherapy
- Irreversible electroporation
- Photodynamic therapy
Treatment Side Effects
Understanding potential side effects helps patients make informed treatment decisions and manage expectations.
Surgery Side Effects
- Urinary incontinence: Usually improves over 6-12 months
- Erectile dysfunction: Depends on nerve-sparing and pre-surgery function
- Changes in orgasm: Dry orgasm, altered sensation
- Penis shortening: Usually 1-2 cm
- Inguinal hernia risk: Slightly increased
Radiation Side Effects
- Urinary symptoms: Frequency, urgency, burning
- Bowel symptoms: Diarrhea, rectal bleeding, urgency
- Erectile dysfunction: Gradual onset over 1-2 years
- Secondary cancers: Small increased risk
Hormone Therapy Side Effects
- Hot flashes: Most common side effect
- Loss of libido and erectile function: Universal with ADT
- Fatigue and muscle loss: Exercise can help
- Bone loss: Requires monitoring and prevention
- Metabolic changes: Weight gain, diabetes risk, cardiovascular effects
- Cognitive effects: "Brain fog," memory issues
Managing Side Effects: Many side effects can be managed with medications, lifestyle changes, or supportive care. Discuss options with your healthcare team.
Prevention
While prostate cancer cannot be completely prevented, certain lifestyle choices may reduce risk or slow progression.
Dietary Recommendations
- Increase plant-based foods: Vegetables, fruits, whole grains
- Reduce red meat and high-fat dairy: Especially processed meats
- Eat tomato products: Lycopene may have protective effects
- Include cruciferous vegetables: Broccoli, cauliflower, cabbage
- Consider soy products: May have protective effects
- Green tea: Contains beneficial polyphenols
Lifestyle Modifications
- Maintain healthy weight: Obesity linked to aggressive disease
- Exercise regularly: At least 150 minutes moderate activity weekly
- Don't smoke: May reduce risk of aggressive cancer
- Limit alcohol: Moderate consumption if any
Potential Preventive Agents
Under investigation or with mixed evidence:
- 5-alpha reductase inhibitors: Finasteride, dutasteride (reduce risk but controversy exists)
- Aspirin: Some evidence for reduced risk
- Statins: Mixed evidence
- Vitamin D: Adequate levels may be protective
- Selenium and Vitamin E: Not recommended (SELECT trial showed no benefit)
When to See a Doctor
Early detection improves outcomes. See your healthcare provider for:
Screening Discussion
- Age 50 for average-risk men
- Age 45 for high-risk men (African American or family history)
- Age 40 for very high-risk men (multiple affected relatives)
Concerning Symptoms
- Difficulty starting or stopping urination
- Frequent urination, especially at night
- Weak or interrupted urine flow
- Pain or burning during urination
- Blood in urine or semen
- New erectile dysfunction
- Pain in lower back, hips, or pelvis
Seek immediate care for:
- Complete inability to urinate (urinary retention)
- Severe bone pain with weakness or numbness
- Signs of spinal cord compression (leg weakness, numbness, loss of bowel/bladder control)
Medical Disclaimer: This information is for educational purposes only and should not replace professional medical advice. Always consult with a qualified healthcare provider for diagnosis and treatment of any medical condition.