Definition of tumor - NCI Dictionary of Cancer Terms

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tumor (TOO-mer)

An abnormal mass of tissue that results when cells divide more than they should or do not die when they should. Tumors may be benign (not cancerous), or malignant (cancerous). Also called neoplasm.

Previous Definitions:	tuberculosis, tuberous sclerosis, tubulin, tubulovillous adenoma, tui na
Next Definitions:	tumor antigen vaccine, tumor board review, tumor burden, tumor debulking, tumor infiltrating lymphocyte