What causes the PSA to rise?

Anything that irritates or inflames the prostate can increase the PSA, such as a urinary tract infection, prostatitis, prostate stones, a recent urinary catheter or cystoscopy (a look into the bladder through a specialized telescope-like instrument), recent prostate biopsy, or prostate surgery. Sexual intercourse may increase the PSA up to 10%, and a vigorous rectal examination or prostatic massage before the PSA blood test is drawn may also increase the PSA. Benign enlargement of the prostate (BPH) may also increase the PSA because more prostate cells are present, thus more PSA is produced (see Question 3).

Prostate cancer is composed of both hormonesensitive and hormone-insensitive cells.

Are there medications that may affect the PSA? Does testosterone therapy cause the PSA to increase?

Yes, some medications can affect the PSA. Finasteride (Proscar) and Dutasteride (Avodart), medications used to shrink the prostate in men with benign enlargement of the prostate, decrease the PSA up to 50%. This decrease in PSA occurs predictably no matter what your initial PSA is. Any sustained increases in PSA while you are taking Proscar or Avodart (provided that you are taking the Proscar or Avodart regularly) should be evaluated. The percentage of free PSA (the amount of free PSA/the amount of total PSA) is not significantly decreased by these medications and should remain stable while you are taking Proscar or Avodart. Other medications that can decrease the amount of testosterone produced by your testicles, such as ketoconazole, may decrease the PSA. Decreasing the amount of testosterone may cause both benign and cancerous prostate tissue to shrink. Testosterone is broken down in the body to a chemical, dihydrotestosterone, which is responsible for the stimulation of prostate growth. Thus, the addition of testosterone may stimulate the growth of normal prostate cells and possibly prostate cancer cells. Because normal prostate cells produce PSA, it is not unreasonable to expect that an increase in the normal cells present in the prostate would lead to an increase in the PSA. Prostate cancer is composed of both hormone-sensitive and hormone-insensitive cells. The hormone-insensitive cells grow regardless of the availability of testosterone or its breakdown products, whereas the hormone-sensitive cells appear to be dependent on the male hormone for growth. Thus, the addition of testosterone may affect the growth of these hormone-sensitive cells. Testosterone therapy has not been shown to cause the development of prostate cancer.

Are there any other blood tests to check for prostate cancer?

Early Prostate Cancer Antigen (EPCA) and EPCA-2 have been demonstrated to be plasma-based markers for prostate cancer. EPCA is found throughout the prostate and represents a field effect associated with prostate cancer, whereas, EPCA-2 is found only in the prostate cancer tissue. However, EPCA-2 is able to get into the plasma, the liquid part of the blood, allowing for it to be detected by a blood test. In preliminary studies, EPCA-2 has been able to identify men with prostate cancer who had normal PSA levels. This data, however, is preliminary and further studies are needed to validate the sensitivity and specificity of these markers. Others are investigating the ability for urinary markers to detect prostate cancer, specifically alphamethylacyl-CoA racemase (AMACR) and prostate cancer antigen 3 (PCA 3) urinary transcript levels obtained from urine sediments following digital rectal examination and pro-static massage.

 
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