FIGURE 1. ^99mTc-exametazime mammoscintigraphy (500 MBq) of a 60-y-old woman in whom a 35-mm breast tumor was found at mammography. (A) Image showing tumor activity (arrow). (B) Same image showing ROIs used when evaluating patients of the comparative study (group II). Tumor ROI (yellow) is surrounded by 4-pixel-wide background ROI (red).