Prostate-specific antigen (PSA) is a protein produced by both healthy and cancerous cells in the prostate gland. While a small amount of this protein is normally found in the blood, PSA blood levels are usually elevated in men who have prostate cancer.
As with all cancers, early detection of prostate cancer is important to ensure timely and appropriate treatment. Additionally, this type of cancer, which is very common, tends to progress gradually over the course of many years and may not show symptoms in its earliest stages. To screen men for early signs of prostate cancer, a relatively simple blood test known as a PSA test may be recommended. This test, which measures the level of PSA in the blood, is often performed along with a digital rectal exam.
What is a normal PSA test result?
PSA blood levels can fluctuate for many reasons – even in the same man over time – so there is no specific level or range that is considered to be “normal.” For instance, some factors that can affect the level of PSA in the blood include:
- Prostatitis (inflammation of the prostate)
- Benign prostatic hyperplasia (BPH) (enlargement of the prostate)
- A urinary tract infection
- A prostate biopsy
- Prostate surgery
- Certain medications, including finasteride and dutasteride, which are often prescribed for treating BPH
In general, however, the likelihood of prostate cancer increases along with blood PSA levels. If a relatively high PSA level (approximately 4.0 ng/mL or above) is detected, most physicians recommend repeat testing supplemented by other noninvasive tests, such as an MRI scan, rather than immediately ordering a biopsy.
Medically reviewed by Monica Chatwal, MD.
Because the PSA test is imperfect and can sometimes lead to unnecessary testing and procedures, the decision to be tested should be made with the guidance of a trusted physician. If you have questions about PSA testing or prostate cancer PSA levels, you are encouraged to talk with an oncologist in the Genitourinary Oncology Program at Moffitt Cancer Center. To request an appointment, call 1-888-663-3488 or complete our new patient registration form online.