Quantification of perfusion and permeability in breast tumors with a deconvolution-based analysis of second-bolus T1-DCE data

Purpose: To test the feastibility of using a second-bolus injection, added to a routine breast MRI examination, to measure regionasl perfusion and permeability in human breast tumors. Materials and Methodsd: In 30 pastients with breast tumors, first a routine whole-breast T1-DCE sequence was applied, and the slice where the lesion enhanced maximally was located. At the slice position, T1-weighted MR images were acquired at 0.3-second resolution using a second-bolus dynamic inversion recovery (IR)-prepared turbo field echo (TFE) sequence. A pixel-by-pixel model-independent deconvolution of the relative signal enhancement was performed to estimate the tumor blood fow (TBF), tumor volume of distribution (TV), mean transit time (E). In addition to this pilot study, a first appraisal of its sensitivity of tissue type wa made on the basis of a small patient cohort. Results: In the malignant tumors, the parametric maps clearly delineated tumors from the breast tissue and enabled visualization of the heterogeneity. The deconvolution analysis provided objective para,etric maps of tumor perfusion with a mean TBF (84 +/- 48 mL / 100 mL / minute) in malignant tumors in the high range of literature values. Conclusions: In terms of these perfusion values, our method appears promising to quantitatively characterize tumor pathophysiology. However, the number of patients was limited, and the separation between malignant and benign groups was not clear-cut. Additional parameters generated through compartment modelding may inprove the dtumor differentiation.