Dynamic contrast-enhanced MRI (DCE-MRI) plus diffusion weighted imaging (DWI) can accurately diagnose residual or recurrent prostate cancer in patients treated with high-intensity focused ultrasonic ablation, a new study shows.
The study included 27 patients who had increased levels of prostate specific antigen after being treated with high-intensity focused ultrasonic (HIFU) ablation; 18 of these patients had local tumor progression seen at biopsy. DCE-MRI and DWI had about a 72% accuracy rate in determining which patients needed additional treatment because they had residual or recurrent cancer, said Chan Kyo Kim, MD, lead author of the study. The study found that DWI had fewer false positives than DCE-MRI, but DCE-MRI had fewer false negatives.
"After HIFU ablation, the normal anatomy of the prostate gland is completely lost or deformed making it difficult to distinguish benign tissue from cancer," said Dr. Kim. The two imaging studies together, which can be done in about seven minutes, can overcome that challenge, he said.
HIFU is becoming more common as a prostate cancer treatment option, particularly for those persons who can't or don't want to undergo a radical prostatectomy, said Dr. Kim.
The study appears in the May issue of the American Journal of Roentgenology, published by the American Roentgen Ray Society.