1) Malignant neoplasm 2) Malignant tumor 3) Metastatic tumor 
A term used to describe a condition that may (or is likely to) become cancer. Also called premalignant.
<pathology> In a very early stage of cancer development and abnormal changes occur in tissue as a pre-determinant for possible future malignancy. ... (31 Dec 1997) ... 
(pre-kan´sәr-әs) pertaining to a pathologic process that tends to become malignant; called also premalignant.
A condition that shows cellular changes that indicate it may become cancerous.
Type: Term Pronunciation: prē-kan′sĕr-ŭs Definitions: 1. Pertaining to any lesion that is interpreted as precancer. Synonyms: premalignant
Precancerous: Pertaining to something that is not yet overtly cancerous, but appears to be on its way to becoming a cancer. Synonymous with premalignant.
[adj] - of or relating to a growth that is not malignant but is likely to become so if not treated
precancerous Pertaining to a pathologic process that tends to become malignant.
describes a condition from which cancer is likely to develop 
adjective of or relating to a growth that is not malignant but is likely to become so if not treated
showing pathological changes that may be preliminary to malignancy.