Prostate Cancer - PSA

Prostate cancer is the most frequent malignant neoplasia in men and the second most common cause of cancer death among American men.

Epidemiology

• Prevalence – 6th most common cancer in the world
• Age – risk rises steeply with age
  • <50 years – low risk
  • 75% of cases occur in men ≥65 years

Risk Factors

• Ethnicity – Black race has higher occurrence
• Family history – 5-11 fold increase
• Age – common malignancy in elderly males

Pathophysiology

• Tumors are usually adenocarcinoma and depend on androgen for growth
• Epithelial cells of prostate produce prostate specific antigen and acid phosphatase
  • Production increased with tumors
• Most tumors develop in peripheral zone of prostate

Clinical Presentation

• May have signs and symptoms of enlarged prostate – urgency, frequency of urination
• Metastatic disease
  • Bone pain – pelvis, spine

Diagnosis

• Laboratory testing
  • Prostate specific antigen (PSA)
• Biopsy
  • Sonographically guided biopsy is current means of diagnosis
    • Tumors assigned Gleason score

Differential Diagnosis

• Prostatitis
• Benign prostatic hypertrophy

Disease Monitoring

• Laboratory testing
  • Prostatic specific antigen (PSA)
• Successful surgical resection should lead to concentrations <0.05 ng/mL
• Radiation therapy may not result in levels this low
  • Subsequent rise is indicative of residual disease or metastasis

Disease Screening

• PSA is the only tumor marker available that has been approved for use as a screening test for prostate cancer
• Prostatic acid phosphatase has little value in screening for prostate cancer
• Several forms of PSA are present in serum
  • A greater percentage of free PSA is found in patients with benign conditions of the prostate than in patients with prostate cancer
  • Approximately one-third of patients with PSA levels between 4.1-10.0 ng/mL will have prostate cancer detectable by biopsy within 1 year

Indications for Ordering

• Tests generally appear in the order most useful for common clinical situations
• Click on number for test-specific information in the ARUP Laboratory Test Directory

• Click on number for test-specific information in the ARUP Laboratory Test Directory