Neoplasm

a new or abnormal growth, especially one that is progressive and uncontrolled. Neoplasm is another name for tumour. Typically, the abnormal tissue grows more rapidly than normal and continues to grow after the initiating stimuli have ceased. Neoplasms usually form a distinct mass, and they tend to have partial or complete lack of structural organization and functional coordination with the normal tissue.

Neoplasms may be benign or malignant. Malignant forms are invasive and metastatic. The capacity for metastasis is one of the basic characteristics of all malignant tumours; benign neoplasms do not metastasize. Degree of differentiation (malignant tumours have a greater degree of anaplasia than benign tumours) and rate of growth are other features by which lesions may differ. Also, see carcinoma, tumour and names of specific neoplasms.