MKI67 and breast cancer: In the recent recommendations from the International Ki-67 in Breast Cancer Working Group [24], the authors stated that the Ki-67 evaluation method can be based on three patterns of Ki-67 immunostaining: homogeneous, hot spots, and a gradient of increasing staining toward the tumor edge; however, the most commonly used method to calculate the Ki-67 index is based on the hot spots, which also includes studies of prognostic value [12-14,22].