RESEARCH HIGHLIGHTS Nature Reviews Urology advance online publication 20 January 2015; doi:10.1038/nrurol.2015.2
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New imaging method to improve prostate cancer detection A newly developed imaging technique might improve the detection and characterization of prostate cancer and spare some patients from prostate resection, according to a study by collaborators at the University of California San Diego and University of California Los Angeles. “Standard-of-care prostate MRI depends in part on contrast-enhanced MRI,” says Anders Dale—senior author on the paper, “but unfortunately many tumours are missed with just contrast uptake as some prostate cancers do not significantly differ in contrast-enhanced characteristics compared with the surrounding healthy tissue. Although diffusion MRI improves on the sensitivity and specificity of standard contrast-enhanced MRI, it fails to accurately localize tumours as it is susceptible to magnetic field artifacts that can distort the actual location of tumours.” The novel technique developed by the authors is known as restriction spectrum imaging (RSI)-MRI and is an enhanced
diffusion MRI technique that corrects for magnetic field distortion and focuses on the intracellular diffusion component of tumour cells. By correcting for distortion, RSI-MRI improves the accuracy of MRI to localize tumours.
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…RSI-MRI will be valuable in predicting tumour grade and likely will have added value in surveillance monitoring…
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Rakow-Penner et al. compared the efficacy of their new RSI-MRI technique with the efficacy of standard MRI for detecting extraprostatic extension (before radical prostatectomy) in 27 patients with prostate cancer. They found that preoperative standard MRI correctly detected extraprostatic extension in two of nine patients (22%) with histologically proven pT3 disease; by contrast, RSI-MRI identified extraprostatic extension in eight of nine patients (89%).
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Rakow-Penner and co-workers also found that RSI-MRI correctly identified pT2 disease in the other 18 patients. In another study, the same researchers found that RSI-MRI seems to be able to predict tumour grade, with higher-grade tumours correlating with higher restricted water volume in the large nuclei of cancer cells. “Our results show that RSI-MRI will be valuable in predicting tumour grade and likely will have added value in surveillance monitoring,” says David Karow, corresponding author. “If by imaging, we could predict the tumour grade, we may be able to spare some patients from prostate resection and monitor their cancer with imaging.” Rebecca Kelsey Original article Rakow-Penner, R. A. et al. Novel technique for characterizing prostate cancer utilizing MRI restriction spectrum imaging: proof of principle and initial clinical experience with extraprostatic extension. Prostate Cancer Prostatic Dis. doi:10.1038/pcan.2014.50
ADVANCE ONLINE PUBLICATION © 2015 Macmillan Publishers Limited. All rights reserved
PROSTATE CANCER
New imaging method to improve prostate cancer detection A newly developed imaging technique might improve the detection and characterization of prostate cancer and spare some patients from prostate resection, according to a study by collaborators at the University of California San Diego and University of California Los Angeles. “Standard-of-care prostate MRI depends in part on contrast-enhanced MRI,” says Anders Dale—senior author on the paper, “but unfortunately many tumours are missed with just contrast uptake as some prostate cancers do not significantly differ in contrast-enhanced characteristics compared with the surrounding healthy tissue. Although diffusion MRI improves on the sensitivity and specificity of standard contrast-enhanced MRI, it fails to accurately localize tumours as it is susceptible to magnetic field artifacts that can distort the actual location of tumours.” The novel technique developed by the authors is known as restriction spectrum imaging (RSI)-MRI and is an enhanced
diffusion MRI technique that corrects for magnetic field distortion and focuses on the intracellular diffusion component of tumour cells. By correcting for distortion, RSI-MRI improves the accuracy of MRI to localize tumours.
‘‘
…RSI-MRI will be valuable in predicting tumour grade and likely will have added value in surveillance monitoring…
’’
Rakow-Penner et al. compared the efficacy of their new RSI-MRI technique with the efficacy of standard MRI for detecting extraprostatic extension (before radical prostatectomy) in 27 patients with prostate cancer. They found that preoperative standard MRI correctly detected extraprostatic extension in two of nine patients (22%) with histologically proven pT3 disease; by contrast, RSI-MRI identified extraprostatic extension in eight of nine patients (89%).
NATURE REVIEWS | UROLOGY
Rakow-Penner and co-workers also found that RSI-MRI correctly identified pT2 disease in the other 18 patients. In another study, the same researchers found that RSI-MRI seems to be able to predict tumour grade, with higher-grade tumours correlating with higher restricted water volume in the large nuclei of cancer cells. “Our results show that RSI-MRI will be valuable in predicting tumour grade and likely will have added value in surveillance monitoring,” says David Karow, corresponding author. “If by imaging, we could predict the tumour grade, we may be able to spare some patients from prostate resection and monitor their cancer with imaging.” Rebecca Kelsey Original article Rakow-Penner, R. A. et al. Novel technique for characterizing prostate cancer utilizing MRI restriction spectrum imaging: proof of principle and initial clinical experience with extraprostatic extension. Prostate Cancer Prostatic Dis. doi:10.1038/pcan.2014.50
ADVANCE ONLINE PUBLICATION © 2015 Macmillan Publishers Limited. All rights reserved
