Diagnosing Prostate Cancer
Diagnosing prostate cancer involves several tests. During a routine examination your doctor will usually take a thorough medical history and ask questions about your urinary function. Your doctor may also have you fill out a form or answer questions based on the International Prostate Symptoms Test or Chronic Prostatitis Symptom Index.
Although certain answers to these questions can suggest that the prostate is diseased, at this point exactly what the problem is cannot be determined without further testing.
Tests for Diagnosing Prostate Cancer
These tests include:
- Digital rectal examination (DRE): This test is the “gold standard” for checking on prostate health. For the DRE, a doctor inserts inserts a lubricated finger into the rectum to check for any irregularities in the shape and size of the prostate. Read more on the DRE
- PSA (prostate-specific antigen) test: The PSA test is a simple blood test that measures the levels of prostate specific antigen in the bloodstream. The blood level of PSA generally rises when cancer is present however, a high PSA level is not necessarily a sign of prostate cancer because several other factors can cause the level to increase. Read more on the PSA test
- TRUS: A transrectal prostate ultrasound allows your doctor to get a picture of your prostate via an ultrasound probe that is inserted into the rectum. Although the TRUS is not 100 percent reliable as a way to detect prostate tumors, it does find some that escape the DRE. The TRUS can also help your doctor estimate the size of your prostate, which is used to calculate the PSA density. This information helps doctors differentiate between prostate cancer and prostate enlargement. Generally, a PSA density greater than 15 percent suggests (but does not definitively identify) prostate cancer, while a lower density suggests BPH. Read more on the transrectal ultrasound.
- Prostate biopsy: This “snip-a-piece” procedure (biopsy) allows your doctor to take small core samples of prostate tissue for examination in a laboratory. If cancer is found, it can be “staged” and “graded” according to a number of factors. More on the prostate biopsy procedure. In some cases, although cancer is not initially found, doctors may discover something called PIN which are irregular, but not cancerous cells in the prostate, that some experts believe set the stage for cancer in some men. PIN is graded “high” or “low” depending on the extent of the cellular irregularity. More on PIN
- Other Imaging Techniques: Other imaging used for diagnosing prostate cancer may include an MRI and/or a PET/CT scan. A MRI uses a magnetic field, radio waves, and a computer to produce very clear pictures of internal structures without the use of x-rays. Images from an MRI can provide physicians with information that may not be visualized adequately using x-rays, ultrasound, or computed tomography (CT) More on the MRI A PET/CT scan is a type of nuclear imaging technique that uses small amounts of radioactive materials to diagnose or treat diseases. Clinicians turn to a PET scan for diagnosing prostate cancer to help them determine if the cancer has spread and if it has, where it is located. A PET scan is noninvasive and painless except for the intravenous injections of the radioactive materials. More on the PET/CT scan