A lesion from which a malignant neoplasm is believed to develop in a significant number of instances, and which may or may not be recognizable clinically or by microscopic changes in the affected tissue. ... (05 Mar 2000) ... 
(pre´kan-sәr) a condition that tends to become malignant (see cancer). adj., precan´cerous., adj.
Type: Term Pronunciation: prē-kan′sĕr Definitions: 1. A lesion from which a malignant neoplasm is believed to develop in a significant number of instances, and that may or may not be recognizable clinically or by microscopic changes in the affected tissue.
precancer A condition which tends eventually to become malignant.