Transrectal ultrasound microbubble contrast angiography of the prostate

BACKGROUND: Prostate cancer, suspected by serum prostate-specific antigen (PSA) elevation and/or digital abnormalities, is not always evident on gray-scale or color Doppler transrectal ultrasound (TRUS). EchoGen (Sonus Pharmaceuticals, Inc., Bothell, WA), a blood vessel image enhancer able to visualize smaller, low-flow vessels and thus possibly the microvascular angiogenesis often associated with cancer, was employed to see if it would improve prostate cancer detection, particularly in patients with a rising serum PSA and prior negative biopsies. METHODS: Color Doppler TRUS was performed before and after intravenous injection of 0.05 ml/kg of EchoGen. Random and/or specifically directed sextant TRUS biopsies were performed. RESULTS: Fifteen patients with serum PSA elevations were included in the study. Fourteen had a negative prior biopsy (1-3 x). Prostate cancer was detected in 5 patients. Microvascular patterns were judged abnormal in 8 patients, 2 of which proved malignant, 2 of which were benign, and 1 of which was diagnosed with prostatis. False-negative results were observed in 3 patients, whose positive biopsy sites were from the prostate apex. CONCLUSIONS: Following EchoGen administration, prostate blood vessel image enhancement was noted in all patients, and there were no adverse reactions during or after EchoGen administration with the dose employed.