Transrectal colour Doppler contrast sonography in the diagnosis of local recurrence after radical prostatectomy - Comparison with MRI

Objective: To assess the usefulness of colour power-Doppler transrectal sonography before/after contrast agent in the detection of local recurrence in patients with rising prostate-specific antigen values after radical prostatectomy and to compare with magnetic resonance imaging. Materials and Methods: 18 patients with rising prostate-specific antigen values after prostatectomy underwent digital rectal examination, bone scintigraphy, magnetic resonance imaging, transrectal colour power-Doppler sonography before/after contrast agent, and transrectal sonography-guided biopsy. Sensitivity, specificity, accuracy, positive and negative predictive values were calculated. Results were correlated using McNemar binomial 2-tailed P-test. Results: Baseline and contrast-enhanced transrectal colour power-Doppler sonography and contrast-enhanced magnetic resonance imaging identified recurrent disease in 6, 10 and 10 patients, respectively. Biopsy confirmed recurrence in 10 patients, but was positive also in 2 additional patients who were negative at contrast-enhanced transrectal colour power-Doppler sonography and contrast-enhanced magnetic resonance imaging. The remaining 6 patients were negative also at diagnostic imaging and biopsy after 30 days. Grey-scale transrectal sonography values were: sensitivity 91.7%, specificity 66%, PPV 91.6%, NPV 40%. Baseline colour power-Doppler transrectal sonography values were: sensitivity 38.5%, specificity 85%, diagnostic accuracy 50%, PPV 83.3%, NPV 33.3%. Contrast enhanced colour powerDoppler transrectal sonography and magnetic resonance imaging values were: sensitivity 76.9%, specificity 100%, diagnostic accuracy 83.3%, PPV 100%, NPV 62.5%. Conclusion: Contrast-enhanced transrectal colour power-Doppler sonography increases specificity in the detection of local recurrence after prostatectomy. Magnetic resonance imaging yields equivalent accuracy. Biopsy remains the diagnostic gold standard, but the use of imaging methods may reduce the number of biopsies.