AIM: The purpose of this study was to observe the morphological features of neuroendocrine cells(NECs),their proliferation and apoptosis in ovarian epithelial tumors,and to discuss their biological and clinical significance.METHODS: 79 specimens of ovarian epithelial tumor samples were collected,of them 20 benign,18 boderline,41 milignant tumors,and 22 normal ovaries were investigated immunohistochemically.Chromogranin A was used to detect NECs and their proliferation and apoptosis were examined by double-label staining of chromogranin A and Ki67 or TUNEL.RESULTS: The positive rate of CgA,distribution and staining intensity in ovarian epithelial tumors were higher than those in normal ovary.NECs showed various shapes with neuronoid protuberances stretching to the neighboring cells or basement membrane.Occasionally,they might touch together.No TUNEL positive coexpression in all NECs was observed by double-label staining,but some NECs were coexpressed with Ki67.CONCLUSION: NECs of ovarian epithelial tumors like cancer cells showed a proliferation,but no apoptosis.Their secretion might promote their neighboring non-NECs to proliferate and prevent them from apoptosis.