Is extended biopsy protocol justified in all patients with suspected prostate cancer?

To determine the significance of an extended 10-core transrectal biopsy protocol in different categories of patients with suspected prostate cancer using digital guidance.

We studied 125 men who were being evaluated for prostate cancer. They all had an extended 10-core digitally guided transrectal prostatic biopsy done for either an elevated serum prostate-specific antigen (PSA) or an abnormal digital rectal examination finding or both. Sextant biopsy samples were collected first, followed by additional four lateral biopsies in all patients. Both groups of specimens were analyzed separately. The cancer detection rates of both sextant and extended 10-core biopsy protocols at different PSA levels and digital rectal examination (DRE) findings were determined and compared. The level of significance of difference in cancer detection was determined using Pearson's Chi square test with level of significance set at <0.05.

The overall cancer detection by the extended technique was 61 (48.8%) cases while the sextant protocol detected cancer in 52 cases. The 10-core extended protocol yielded an increase in cancer detection rate of 14.8% but the improvement in detection rate was only statistically significant in the sub-set of patients with PSA between 4.1 and 10 ng/mL, with or without abnormality on DRE, with an overall increase detection rate of 33%.(P=0.04)

Our study has shown that a 10-core prostate biopsy protocol significantly improves cancer detection in patients with suspected early cancer. It should therefore be the optimum biopsy protocol for patients with gray-zone PSA value, with or without abnormal DRE.