A new method for apparent diffusion coefficient measurement using sequential F-18-FDG PET and MRI: correlation with histological grade of invasive ductal carcinoma of the breast

作者：Byun Byung Hyun; Noh Woo Chul; Lim Ilhan; Lee Seung Sook; Cho A Ra; Park Ji Ae; Kim Kyeong Min; Kim Hyun Ah; Kim Eun Kyu; Kim Byung Il; Choi Chang Woon; Lim Sang Moo^*

来源：Annals of Nuclear Medicine, 2013, 27(8): 720-728.

DOI：10.1007/s12149-013-0737-1

• ADC
• PET-MRI
• Breast cancer
• Histological grade

The aim of this study was to measure the apparent diffusion coefficient (ADC) value at the region with the highest FDG uptake using sequential F-18-FDG PET and MRI, and to correlate it with the histological grade of invasive ductal carcinoma (IDC) of the breast.
A retrospective study was conducted on 75 untreated patients with IDC. First, a PET/CT scan and subsequent breast MRI were done and the SUVmax of the each breast tumor was recorded. Then, a PET image and ADC map were co-registered. On the axial slice containing the pixel with SUVmax, we drew multiple circular ROIs within the tumor and measured the mean ADC value of each ROI. The average (ADC-mean) and minimum (ADC-min) of the mean ADC values for all ROIs within the tumor were calculated, respectively. Then, a circular ROI was placed at the corresponding location to the pixel with the highest SUV and the mean ADC value of the ROI was denoted as ADC-PET. We compared the averages of the ADC parameters and assessed the correlations among SUVmax and ADC parameters. ROC curve and logistic regression analyses were performed to assess the utility of ADC and SUVmax for detecting histological grade 3.
ADC-min was significantly lower than the ADC-mean or ADC-PET. All of the ADC parameters showed a negative correlation with SUVmax. The area under the ROC curve for identifying histological grade 3 using ADC-PET, ADC-min, ADC-mean and SUVmax was 0.684, 0.660, 0.633 and 0.639, respectively. By multivariate analysis, ADC-PET was a significant, independent predictor of histological grade 3 (p = 0.004).
We estimated the ADC value at the breast tumor region with the highest FDG uptake using sequential F-18-FDG PET and MRI. This new ADC parameter distinguished high-grade IDC, supporting the feasibility of the combined PET-MRI system in patients with breast cancer.

• 出版日期2013-10