Radiology: Enhanced MRI may improve breast cancer diagnosis
Researchers found the use of shutter-speed dynamic contrast-enhanced MRI has potential to improve breast cancer diagnostic accuracy and reduce biopsy procedures that often yield benign pathologic findings, according to a study published Aug. 9 in Radiology.
“Shutter-speed pharmacokinetic analyses of dynamic contrast-enhanced MR imaging data seemed to provide the long-sought combination of high sensitivity and specificity for breast cancer diagnosis,” wrote Wei Huang, PhD, associate scientist at the Oregon Health & Science University in Portland, Ore., and colleagues.
Conventional x-ray mammography—used for screening and diagnostic imaging—has a high false-positive rate, as well as substantial undesirable consequences, suggesting that mammographic effectiveness is “less than desired,” the authors wrote.
Meanwhile, higher sensitivity in malignancy detection has increased use of breast MRI for high-risk population screening, dense breast imaging, preoperative staging, therapy monitoring and residual disease assessment, wrote Huang et al.
Unfortunately, MRI is coupled with significantly higher costs and current implementation has limited diagnostic accuracy and reproducibility, according to the study. Contrast-enhanced MR imaging has become routine in clinical breast MR imaging, but results often depend on the imager—magnetic field strength, vendor—and other factors that limit specificity and reproducibility.
The authors pointed to a study of the application of shutter-speed approach analyses that included six patients with lesions visible at mammography and 16 patients with lesions occult at mammography, which resulted in 100 percent specificity at 100 percent sensitivity for benign and malignant breast lesion discrimination. The recent findings add to a body of evidence supporting the shutter-speed MR method.
“The purpose of this study was to assess the accuracy of the shutter-speed approach compared with standard approach dynamic contrast-enhanced MR imaging analysis for breast cancer diagnosis,” the authors wrote.
Researchers studied results from high-risk patients scheduled for MRI-guided core-needle biopsy or preoperative needle localization procedures from February 2007 to April 2009. Of 89 women recruited for the study, a routine exam with clinical diagnostic breast MR imaging protocol indicated 92 suspicious breast lesions that were negative at mammography.
To assess diagnostic accuracy, biopsy pathologic findings were used as reference standards in correlation analysis with research dynamic contrast-enhanced MRI results.
“There were 62 MR imaging-guided core-needle biopsies and 30 preoperative needle localization procedures. The latter led directly to excisional biopsies,” wrote Huang et al. “If core-needle biopsy procedures were followed by excisional biopsies as standard care, because core-needle biopsy results revealed cancer or atypical pathologic results, the pathologic results from the latter were used to correlate with MR imaging results.”
Pathologic analyses indicated that 20 lesions were malignant and 72 were benign, according to the study, and researchers noted that the institutional clinical breast MR imaging protocol had a positive predictive value for biopsy of 22 percent.
In the entire population, with one exception of a benign tubular adenoma identified as malignant, “all other lesions were correctly classified with the combined region of interest and mapping and/or histographic analysis approach, improving the diagnostic accuracy to 98.6 percent specificity and 100 percent sensitivity,” wrote Huang et al.
“For patients with lesions with negative findings as mammographic screening and follow-up mammographic or sonographic diagnostic imaging results, the shutter-speed approach contrast-enhanced MR imaging method may potentially be used to improve diagnostic accuracy and reduce putatively unnecessary biopsies,” the authors concluded.
“Shutter-speed pharmacokinetic analyses of dynamic contrast-enhanced MR imaging data seemed to provide the long-sought combination of high sensitivity and specificity for breast cancer diagnosis,” wrote Wei Huang, PhD, associate scientist at the Oregon Health & Science University in Portland, Ore., and colleagues.
Conventional x-ray mammography—used for screening and diagnostic imaging—has a high false-positive rate, as well as substantial undesirable consequences, suggesting that mammographic effectiveness is “less than desired,” the authors wrote.
Meanwhile, higher sensitivity in malignancy detection has increased use of breast MRI for high-risk population screening, dense breast imaging, preoperative staging, therapy monitoring and residual disease assessment, wrote Huang et al.
Unfortunately, MRI is coupled with significantly higher costs and current implementation has limited diagnostic accuracy and reproducibility, according to the study. Contrast-enhanced MR imaging has become routine in clinical breast MR imaging, but results often depend on the imager—magnetic field strength, vendor—and other factors that limit specificity and reproducibility.
The authors pointed to a study of the application of shutter-speed approach analyses that included six patients with lesions visible at mammography and 16 patients with lesions occult at mammography, which resulted in 100 percent specificity at 100 percent sensitivity for benign and malignant breast lesion discrimination. The recent findings add to a body of evidence supporting the shutter-speed MR method.
“The purpose of this study was to assess the accuracy of the shutter-speed approach compared with standard approach dynamic contrast-enhanced MR imaging analysis for breast cancer diagnosis,” the authors wrote.
Researchers studied results from high-risk patients scheduled for MRI-guided core-needle biopsy or preoperative needle localization procedures from February 2007 to April 2009. Of 89 women recruited for the study, a routine exam with clinical diagnostic breast MR imaging protocol indicated 92 suspicious breast lesions that were negative at mammography.
To assess diagnostic accuracy, biopsy pathologic findings were used as reference standards in correlation analysis with research dynamic contrast-enhanced MRI results.
“There were 62 MR imaging-guided core-needle biopsies and 30 preoperative needle localization procedures. The latter led directly to excisional biopsies,” wrote Huang et al. “If core-needle biopsy procedures were followed by excisional biopsies as standard care, because core-needle biopsy results revealed cancer or atypical pathologic results, the pathologic results from the latter were used to correlate with MR imaging results.”
Pathologic analyses indicated that 20 lesions were malignant and 72 were benign, according to the study, and researchers noted that the institutional clinical breast MR imaging protocol had a positive predictive value for biopsy of 22 percent.
In the entire population, with one exception of a benign tubular adenoma identified as malignant, “all other lesions were correctly classified with the combined region of interest and mapping and/or histographic analysis approach, improving the diagnostic accuracy to 98.6 percent specificity and 100 percent sensitivity,” wrote Huang et al.
“For patients with lesions with negative findings as mammographic screening and follow-up mammographic or sonographic diagnostic imaging results, the shutter-speed approach contrast-enhanced MR imaging method may potentially be used to improve diagnostic accuracy and reduce putatively unnecessary biopsies,” the authors concluded.