A new study carried out by the Medical University of Vienna in Austria has shown than imaging breast tumours using four approaches together can better distinguish malignant breast tumours from those that are benign and this may help avoid repeat breast biopsies.
The new imaging technique is called multi-parametric (MP) 18FDG PET-MRI, and uses four imaging approaches. It was shown to be 96 per cent accurate in distinguishing malignant breast tumours from those that were benign, and provided better results than combinations of two or three imaging approaches. The study estimates that this technique can reduce unnecessary breast biopsies recommended by the commonly used imaging method, the DCE-MRI, by 50 per cent.
Dr Katja Pinker, Associate Professor of Radiology in the Department of Biomedical Imaging and Image-guided Therapy said: "By assessing many functional processes involved in cancer development, a multi-parameter PET-MRI of the breast allows for a better differentiation of benign and malignant breast tumours than the currently used DCE-MRI alone. Therefore, unnecessary breast biopsies can be avoided."
"DCE-MRI is a very sensitive test for the detection of breast tumours, but is limited in visualizing the functional properties cancer cells acquire during development. Therefore, there is still room for improvement," explained Dr Pinker. "PET-MRI mirrors cancer biology and allows accurate diagnosis of breast cancer without a biopsy. Additionally, the more accurately we understand a tumour’s biology, the better we can tailor therapy to each breast cancer patient's individual needs.
"Provided that a hospital is equipped with a PET-CT and an MRI scanner or a combined PET-MRI, the technique we have described can be immediately implemented in clinics," said Pinker.
The study involved 76 patients who had suspicious or inconclusive findings from a mammography or a breast ultrasonography. They performed a MP18FDG PET-MRI on all the patients. In addition, all patients' breast tumour biopsies were evaluated by histopathology.
To determine the combination of imaging parameters that yielded the most accurate results, Dr Pinker and colleagues combined the imaging data from two parameters, three parameters, and all four parameters. All two-parameter and three-parameter evaluations included DCE-MRI.
All results were compared with histopathology diagnosis to evaluate which combination was most efficient in making an accurate diagnosis. Of the 76 tumours, 53 were malignant and 23 were benign, based on histopathology.
The researchers found that none of the two- or three-parameter combinations reached the same level of sensitivity and specificity as the four-parameter method.
"Performing a combined PET-MRI is currently less cost-effective than existing breast imaging methods," said Dr Pinker. "However, a significant reduction in unnecessary breast biopsies by using this combined method may improve the cost-effectiveness."
The study is published in Clinical Cancer Research, a journal of the American Association for Cancer Research.
