title: The value and limitations of contrast-enhanced transrectal ultrasonography for the detection of prostate cancer.
abstract: OBJECTIVE
  To evaluate the role of contrast-enhanced transrectal ultrasonography (CE-TRUS) for detecting prostate carcinoma.
  
  
  METHODS
  Sixty-five patients with elevated serum prostate-specific antigen (PSA) and/or abnormal digital rectal examination (DRE) were assessed using transrectal ultrasound (TRUS) and CE-TRUS. In all the patients, CE-TRUS was performed with intravenous injection of contrast agent (SonoVue, 2.4 ml) before biopsy. The cancer detection rates of the two techniques were compared. False-positive and false-negative findings related to CE-TRUS were analyzed in comparison to the pathological results of biopsy or radical prostatectomy. The targeted biopsy to abnormal CE-TRUS areas was also compared to systematic biopsy.
  
  
  RESULTS
  Prostate cancer was detected in 29 of the 65 patients. CE-TRUS showed rapid focal enhancement or asymmetric vessels of peripheral zones in 28 patients; 23 of them had prostate cancer. CE-TRUS had 79.3% sensitivity, compared to 65.5% of TRUS (P<0.05). There were five false-positive and six false-negative findings from CE-TRUS. Benign prostate hyperplasia, and acute and chronic prostatitis were important causes related to the false-positive results of CE-TRUS. Prostate cancer originating from the transition zone or peripheral zone with lower PSA levels, small-size foci, and moderately or well-differentiated tumor was missed by CE-TRUS. The cancer detection rate of targeted biopsy (75%, 33/44 cores) was significantly higher than one of systematic biopsy (48.2%, 162/336) in those 28 cases (P<0.05). In addition, no significant correlation was found between the cancer detection rate with CE-TRUS and serum PSA levels.
  
  
  CONCLUSIONS
  CE-TRUS may improve the detection rate of prostate cancer through targeted biopsy of contrast-enhanced abnormalities. Our findings indicate that systematic biopsies should not be eliminated on the basis of false-positive and false-negative findings related to CE-TRUS.
authors.affiliation: Department of Diagnostic Ultrasound, Beijing Tongren Hospital, Capital Medical University, Dong-Jiao-Min-Xiang, Dong Cheng District, Beijing 100730, PR China. Electronic address: zhaohx861@163.com.
authors.forename: Han-Xue
authors.initials: HX
authors.lastname: Zhao
authors.forename: Chun-Xia
authors.initials: CX
authors.lastname: Xia
authors.forename: Hong-Xia
authors.initials: HX
authors.lastname: Yin
authors.forename: Ning
authors.initials: N
authors.lastname: Guo
authors.forename: Qiang
authors.initials: Q
authors.lastname: Zhu
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002681:China / Q000453:epidemiology; D003287:Contrast Media; D006801:Humans; D008297:Male; D008875:Middle Aged; D010743:Phospholipids; D015995:Prevalence; D011379:Prognosis; D011471:Prostatic Neoplasms / Q000000981:diagnostic imaging* / Q000453:epidemiology*; D012007:Rectum; D015203:Reproducibility of Results; D012307:Risk Factors; D012680:Sensitivity and Specificity; D013459:Sulfur Hexafluoride; D014463:Ultrasonography / Q000706:statistics & numerical data*
chemical_list: D003287:Contrast Media; D010743:Phospholipids; C420843:contrast agent BR1; D013459:Sulfur Hexafluoride
keywords: Biopsy; Contrast agent; Prostate neoplasm; Ultrasound