Figure 2.

Survivin, Ki-67, and cleaved caspase-3 expression in reactive tonsil and MCL. A: Adult tonsil. Reactive tonsil showing a number of hyperplastic follicles (hematoxylin and eosin, H&E). Cells expressing survivin, Ki-67, and cleaved caspase-3 were mainly localized in the germinal center of secondary follicles. B: MCL, classical variant. An entrapped reactive germinal center was colonized by tumor cells (H&E). Cyclin D1 staining confirmed the presence of tumor cells inside the reactive germinal center (not shown). Survivin-positive tumor and reactive cells were clustered in a partially involved germinal center. Only very few scattered cells were positive outside the follicle. The proliferative activity of the tumor was low. A very low number of positive cleaved caspase-3 cells were detected in the tumor. Apoptotic activity was mostly concentrated in the entrapped follicles. C: MCL, pleomorphic variant. A high mitotic activity was observed in this tumor (H&E). Survivin-positive cells were widely distributed through the tumor. A high number of Ki-67 positive cells were also detected. A few cells were positive for cleaved caspase-3. D: MCL, blastic variant. Monotonous infiltration by medium-sized lymphocytes with rounded nuclei and dispersed chromatin (H&E). Survivin was widely expressed in tumor cells. Increased proliferative activity was noticed with Ki-67 antigen. A few number of cells were positive for cleaved caspase-3. Original magnification, ×200