Prostate cancer is the most common noncutaneous cancer detected in American men and the second leading cause of cancer-related death in men. In 2018, an estimated 164,690 new cases of prostate cancer were diagnosed and 29,430 deaths resulted in the United States. However, the clinical incidence does not match the prevalence noted at autopsy, where more than 40% of men over 50 years of age are found to have prostatic carcinoma. Further, the prevalence increases with age with 30% of men aged 60–69 years and 67% of men aged 80–89 years found to have the disease at autopsy. Most such occult cancers are small and contained within the prostate gland; few are associated with regional or distant disease. Although the global prevalence of prostatic cancer at autopsy is relatively consistent, the clinical incidence varies considerably (high in North America and European countries, intermediate in South America, and low in the Far East), suggesting that environmental or dietary differences among populations may be important for prostatic cancer growth. A 50-year-old American man has a lifetime risk of 40% for latent cancer, a 16% risk for developing clinically apparent cancer, and a 2.9% risk of death due to prostatic cancer. African-American race, family history of prostatic cancer, and history of high dietary fat intake are risk factors for prostate cancer.
Prostate cancer may manifest as discrete nodules or areas of induration within the prostate on a DRE. However, currently most prostate cancers are detected because of elevations in serum PSA (not DRE findings).
Patients rarely present with signs of urinary retention or neurologic symptoms from epidural metastases and cord compression. Obstructive voiding symptoms are most often due to benign prostatic hyperplasia, which occurs in the same age group. Nevertheless, large or locally extensive prostatic cancers can cause obstructive voiding symptoms. Lymph node metastases can lead to lower extremity lymphedema. Because the axial skeleton is the most common site of metastases, patients may present with back pain or pathologic fractures.
PSA is a glycoprotein produced only by cells, either benign or malignant, of the prostate gland. The serum level is typically low and correlates with the total volume of prostate tissue and tends to increase with age. Measurement of serum PSA is useful in detecting and staging prostate cancer, monitoring response to treatment, and identifying recurrence before it becomes clinically evident. As a screening test, PSA is elevated (greater than 4.0 ng/mL [4.0 mcg/L]) in 10–15% of men. Prostate cancer will be diagnosed in approximately 18–30% of men with PSA 4.1–10 ng/mL (4.1–10 mcg/L) and 50–70% of men with PSA greater ...