Prostate cancer is generally detected with elevated level of serum PSA as suggested by the PSA test. It is rarely symptomatic in the early stages. Complaints like difficulty urinating, decreased flow rate, and frequent urination are mostly associated with benign enlargement of the prostate as men get older. Since prostate cancer actually begins in the peripheral zone (outer area of the prostate, next to the rectum), it causes blockage and difficulty urinating only in the advanced stages. A palpable hardness during rectal examination requires biopsy.

Rectal examination is one of the most important parts of physical examination in urology. During rectal examination, your urologist will check if there is any hardness or irregularity on the outer surface of the prostate, which might be indicative of a tumor. It should be noted that, in 25 percent of the patients diagnosed with prostate cancer, the diagnosis is established with hardness or irregularity detected during digital rectal examination even though the PSA level is within reference range.

PSA is a protein secreted by the glands around the prostate and urethra. It is produced to help liquefy the ejaculate prior to ejaculation. Serum PSA exists in two forms: protein-bound PSA and free PSA. Started to be used recently, free PSA test is a method aimed to facilitate diagnosis of prostate cancer. Whereas the reference range for PSA was accepted as 0-4, the safe limit has been lowered to smaller values due to recent detection of many cancer patients with PSA levels within such range.

Prostate Cancer and Age-Specific Reference Ranges for PSA

With starting use of age-specific reference ranges for PSA, rate of prostate cancer among young men has increased whereas unnecessary biopsy among old men has been reduced.
There are other PSA values that result in suspicion of a tumor:

PSA rate:

If annual increase rate of PSA is over 0.75 ng/ml, biopsy should be considered.

PSA density:

It is calculated by dividing the PSA value by the prostate volume. If PSAD is 0.15 and over, biopsy should be considered.

Prostate biopsy is performed using TRUS. TRUS is an ultrasonography device applied through the rectum. Since it shows the prostate very closely, it is more advantageous than standard abdominal ultrasound. Sometimes, it can be used to get a better look at the prostate instead of performing a biopsy. It is possible to obtain a tissue sample from the targeted area of the prostate tissues by means of a device installed on the transrectal ultrasound machine. The biopsy is performed based on specific templates in consideration of the patient’s age, prostate size, and whether biopsy has been performed before.