Our purpose was to evaluate the relevance of repeat laterally directed sextant prostate biopsy for detection of prostate cancer in high-risk patients.
Material and methods: Our study included 195 men at high risk for prostate cancer (elevated prostate-specific antigen level and/or abnormal prostate detected by digital rectal examination). We consulted the patients in outpatient department of Kaunas University of Medicine Hospital during 2003-2007. We performed transrectal ultrasound-guided laterally directed sextant prostate biopsy in every patient. For the patients with benign histological findings and increased risk of prostate cancer, laterally directed sextant biopsies were repeated.
Results: Prostate cancer was detected in 30.3% of patients (59/195) on the first prostate biopsy, in 13.1% (11/84) on the second prostate biopsy, in 10.3% (4/39) on the third, and in 7.7% (1/13) on the forth biopsy. After all biopsies, prostate cancer was detected in 38.5% (75/195) of patients, and it differed significantly from the percentage of prostate cancer cases detected on the first biopsy (30.3%, P=0.04). We detected 78.7% (59/75) of all prostate cancer cases by the first laterally directed sextant prostate biopsy. The rest 21.3% (16/75) of cases we detected by repeat biopsies. The second laterally directed sextant prostate biopsy revealed additional 14.6% (n=11) of prostate cancer cases and increased the detection of prostate cancer to 93.3% (70/75). At the time of the first prostate biopsy, prostate cancer was diagnosed most frequently when patients had both risk factors: elevated prostate-specific antigen level and abnormal digital prostate examination; prostate cancer was diagnosed in 45.3% of these patients. The odds ratio to detect prostate cancer by the first biopsy in patients with elevated prostate-specific antigen level and abnormal digital prostate examination was 3.7, and odds ratio to detect prostate cancer by repeat biopsies was 4.7.
Conclusions: Repeat ultrasound-guided laterally directed sextant prostate biopsies reveal more cases of prostate cancer as compared to the first prostate biopsy. The majority of prostate cancer cases (93.3%) are detected by the first and second laterally directed sextant prostate biopsies. After the first negative prostate biopsy, we recommend to repeat prostate biopsy in high-risk patients.