Higher perfusion among breast malignant tumors than among breast benign lesions as demonstrated by diffusion-derived 'vessel density' (DDVD): a pilot study.

BACKGROUND

The biomarker diffusion-derived 'vessel density' (DDVD) works on the principle that small blood vessels show high signal when there is no motion probing gradient (b=0 s/mm2) and low signal when even very low b-values diffusion gradients are applied. This study explores whether there is a DDVD pattern difference between malignant tumor (MT) and benign lesion (BL) of the breast.

METHODS

Hospital 1 (Peking University Shenzhen Hospital) enrolled 17 cases including 15 MTs (among them 5 were post-treatment) and 2 BLs. Hospital 2 (Longgang District Maternity & Child Healthcare Hospital of Shenzhen) enrolled 35 cases including 11 MTs (among them 3 were under treatment) and 24 BLs. Diffusion weighted (DW) images of b=0 and 10 s/mm2 were acquired. DDVD was DDVDb0b10 = Sb0/ROIarea_b0 - Sb10/ROIarea_b10, where Sb0 and Sb10 refer to the sum of signals within the selected region-of-interest (ROI) (or pixel) on b=0 and 10 s/mm2 images. DDVD ratio (DDVDr) was: (DDVD of breast lesion)/(DDVD of contralateral breast of similar site). A potential lesion was subjectively classified to have or do not have regional increased DDVD signal (assumed to be increased vascularity) on DDVD pixelwise map (DDVDm).

RESULTS

Breast MT showed higher DDVD ratio values than those of breast BL. A trend was shown that higher Breast Imaging Reporting and Data System (BI-RADS) grade lesions had higher DDVDr value than lower BI-RADS grade lesions. For lesions without 'suspicious increased vascularity' (n=30), 19 cases (63.3%, 19/30) were with BL, 8 cases (26.7%, 8/30) were MT patients post- or under-chemotherapy, and three lesions (10%, 3/30) were MT. However, for these three false negative cases for malignancy with visual assessment, DDVDr suggested two of them were likely to be MT. For lesions with 'suspicious increased vascularity' (n=22), 14 (63.6%, 14/22) were MT, four were inflammatory lesions (18.2%, 4/22), two (9.1%, 2/22) were BL but with 'T2 shine-through', two cases (9.1%, 2/22) had false positivity for malignancy.

CONCLUSIONS

DDVD imaging can provide information on vascularity changes associated with breast lesions. It has the potential to be used as a supplementary diagnostic technique for differentiating benign and malignant breast masses.