Detection of prostate cancer: comparison of cancer detection rates of sextant and extended ten-core biopsy protocols.

AIMS AND OBJECTIVES: To compare the cancer detection rates of sextant and ten- core biopsy protocol amongst patients being evaluated for prostate cancer. PATIENTS AND METHODS: This is a prospective study involving 125 men with suspicion of prostate cancer. They all had an extended 10-core transrectal digitally-guided prostatic biopsy using Tru-Cut needle. Indications for biopsy were presence of one or more of the following: elevated Prostate Specific Antigen (PSA), abnormal Digital Rectal Examination (DRE) findings and abnormal prostate scan. Sextant biopsies were collected first, followed by four lateral biopsies in all patients. Both groups of specimen were kept and analyzsed separately by the same pathologist. The cancer detection rates of sextant and extended (combination of sextant and lateral) 10-core biopsy protocols were determined and compared. Pearson's Chi square and McNemar tests at two degrees of freedom with level of significance set at 0.05 ( P <0.005) were used to determine the statistical significance. RESULTS: The overall cancer detection rate of 10-core prostate biopsy was 48.8%. Of all positive biopsies, the sextant biopsy protocol detected 52 cancers (85.2%) while the lateral biopsy protocol detected 58 cases (95.1%). Three (3) cancers were detected by the sextant protocol only while the lateral protocol detected nine (9) cancers where sextant technique was negative for malignancy. Ten-core extended protocol showed a statistically significant increase of 14.8% over the traditional sextant. (P=0.046). The overall complication rate of ten-core biopsy was 26.4% and the procedure was well tolerated in most patients. CONCLUSION: We conclude that a ten-core prostate biopsy protocol significantly improves cancer detection and should be considered as the optimum biopsy protocol.

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

OBJECTIVE: To determine the significance of an extended 10-core transrectal biopsy protocol in different categories of patients with suspected prostate cancer using digital guidance. MATERIALS AND METHODS: 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. RESULTS: 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) CONCLUSION: 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.