A number of tumor markers have been reported to be associated with the outcome of prostate cancer patients.[20,21] These include:
- Markers of apoptosis including Bcl-2, Bax.
- Markers of proliferation rate, such as Ki67.
- p53 mutation or expression.
- Microvessel density.
- DNA ploidy.
- PTEN gene hypermethylation and allelic losses.
However, none of these has been prospectively validated; and they are not a part of the routine management of patients.
In the United States, most prostate cancers are diagnosed as a result of screening; therefore, symptoms of cancer are infrequent at the time of diagnosis. Nevertheless, local growth of the tumor may produce symptoms of urinary obstruction such as:
- Decreased urinary stream.
- Incomplete bladder emptying.
These symptoms are nonspecific and more indicative of benign prostatic hyperplasia than cancer.
Although rare in the current era of widespread screening, prostate cancer may also present with symptoms of metastases, such as bone pain, pathologic fractures, or symptoms caused by bone marrow involvement.
Needle biopsy is the most common method used to diagnose prostate cancer. Most urologists now perform a transrectal biopsy using a bioptic gun with ultrasound guidance. Over the years, there has been a trend toward taking eight to ten or more biopsy samples from several areas of the prostate with a consequent increased yield of cancer detection after an elevated PSA blood test. Less frequently, a transperineal, ultrasound-guided approach can be used in patients who may be at increased risk of complications caused by using a transrectal approach.
Prophylactic antibiotics, especially fluoroquinolones, are often used prior to transrectal needle biopsies. There are reports of increasing rates of sepsis, particularly with fluoroquinolone-resistant E. coli, and hospitalization after the procedure.[26,27] Therefore, men undergoing transrectal biopsy should be told to seek medical attention immediately if they experience fever after biopsy.
The survival of patients with prostate cancer is related to several factors, including the following:[28,29,30,31,32]
- Extent of tumor.
- Histologic grade of tumor.
- Patient's age and health.
- Prostate-specific antigen (PSA) level.
(Refer to the Surveillance, Epidemiology, and End Results' 5-year and 10-year survival rates.)
Extent of tumor
When the cancer is confined to the prostate gland, long-term prognosis is excellent. Patients with locally advanced cancer are not usually curable, but 5-year survival is still very good. If prostate cancer has spread to distant organs, current therapy will not cure it. Median survival is usually 1 to 3 years, and most of these patients will die of prostate cancer. Even in this group of patients, indolent clinical courses lasting for many years may be observed.
Histologic grade of tumor
Poorly differentiated tumors are more likely to have metastasized before diagnosis and are associated with a poorer prognosis. The most commonly used method to report tumor differentiation is the Gleason score. (Refer to the Pathology section of the General Information About Prostate Cancer section of this summary for more information.)