[Prognostic significance of prostate-specific antigen in defining indications for initial prostate biopsy]

Currently, prostate biopsy remains the main method used to diagnose prostate cancer (PCa). The indication for the procedure is an elevated level of the serum level of the total prostate-specific antigen (PSA). However, the PSA test is organ- but not cancer-specific, and patients may undergo an unnecessary biopsy, which is an invasive procedure associated with a risk of complications. Additional tests have been developed aimed to improve the diagnostic performance of PSA for detecting PCa. They include PSA derivatives such as free PSA fraction, -2proPSA, PSA density, PHI and the free /total PSA fraction.

To investigate the diagnostic accuracy of PSA and its derivatives in detecting benign and malignant diseases of the prostate after an initial prostate biopsy.

The current study analyzed 65 initial biopsies performed due to an elevated serum PSA level and compared them with the results of extended PSA testing with the use of PSA derivatives.

The histological findings consistent with PCa were found in about 30% of initial biopsies performed due to elevated serum levels of total PSA. The incidence of histologically confirmed PCa increased with age, and 70-79 year old men were more likely to have it than 60-69 years old patients. PSA density in 85% of PCa cases exceeded that for benign prostatic hyperplasia (BPH). In all PCa patients, PHI and free /total PSA fraction were greater than 25 and less than 0.15, respectively. In most patients with BPH, the PHI and free /total PSA fraction did not exceed 25 and were greater than 0.15.

1. Initial biopsy triggered by elevated serum level of total PSA allows detection of PCa in about 30% of cases. 2. The age of 60 years and older should be regarded as a risk factor for PCa. The probability of malignant transformation of prostate epithelial cells in men over 70 years of age is greater than in 60-69-year-olds. 3. The density of PSA in men with morphologically verified PCa is statistically significantly greater than that in men with BPH and the threshold value in 85% of cases. 4. Determination of PHI and free/total PSA fraction can improve the accuracy of predicting malignant lesions of the prostate and adjust the indications for histological examination, reduce the number of unnecessary biopsies. 5. When defining indications for initial prostate biopsy in cases with serum PSA varying from 2 to 10 ng/ml, PSA derivatives should be used, including PSA density, prostate health index, and the free /total PSA fraction.

Urologiia (Moscow, Russia : 1999). 2018 Jul [Epub]

S V Popov, R G Guseinov, O N Skryabin, I N Orlov, A G Martov

St. Lukes Clinical Hospital, St. Petersburg, Russia.