A neoplasm, as defined by Willis, is 'an abnormal mass of tissue the growth of which exceeds and is uncoordinated with that of the normal tissues and persists in the same excessive manner after the cessation of the stimuli which evoked the change.'
Premalignant / Precancerous lesion
A morphologically altered tissue in which cancer is more likely to occur than in its apparently normal counterpart. - WHO 1973
Premalignant / Precancerous condition
A generalized state associated with a significantly increased risk of cancer. - WHO 1973
Potentially malignant Oral Diseases
The term Potentially Malignant Disorders was recommended to refer to precancer as it conveys that not all disorders described under this term may transform into cancer. - Warnakulasuriya et al 2007
Leukoplakia
White patch or plaque that cannot be characterized clinically or pathologically as any other disease. - WHO 1973
Leukoplakia should be used to recognize white plaques of questionable risk having excluded (other) known diseases or disorders that carry no increased risk of cancer.
It is to be noted that a lesion of leukoplakia is non-scrappable.
Erythroplakia
A fiery red patch that cannot be characterized clinically or pathologically as any other definable disease. - WHO 1973
Oral Submucous Fibrosis
It is an insidious chronic disease affecting any part of the oral cavity and sometimes the pharynx. Although occasionally preceded by and/or associated with vesicle formation, it is always associated with a juxta- epithelial inflammatory reaction followed by a fibro-elastic change of the lamina propria with epithelial atrophy leading to stiffness of the oral mucosa and causing trismus and inability to eat.
- Pindborg and Associates
Cyst
A cyst is defined as ' a pathological cavity having fluid, semifluid or gaseous contents and which is not created by the accumulation of pus'. Most cysts, but not all, are lined by epithelium. - Kramer, 1974
Oncology: the study of neoplasms
Neoplasm: an uncontrolled new growth of tissue
Tumor: a localized swelling, may or may not be a true neoplasm
Hyperplasia: An increase in the size of a tissue or organ due to an increase in the number of component cells
Hypertrophy: an increase in the size of a tissue or organ due to an increase in the size of component cells
Cancer: a general term for all malignant neoplasms
Carcinoma: a malignant epithelial neoplasm
Sarcoma: a malignant mesenchymal (connective tissue) neoplasm
Hamartoma: a developmental defect characterized by an overgrowth of tissues normal to the organ in which it arises
Teratoma: a neoplasm composed of multiple tissues foreign to the organ in which it arises; may be benign or malignant