CASP3 and neoplasm: In situ histological analysis of serial frozen tumor tissue sections were performed in order to quantify: (i) necrotic areas within the tumors, (ii) density of individual cell death (hematoxylin-eosin [H&E] staining), (iii) apoptosis (terminal deoxynucleotidyl transferase dUTP nick end labeling [TUNEL]) and (iv) cleaved caspase 3 immunohistochemistry in non-necrotic tumor tissues.