- A malignant neoplasm made up of epithelial cells tending to infiltrate the surrounding tissues and give rise to metastases. It is a histological type of neoplasm but is often wrongly used as a synonym for "cancer." (From Dorland, 27th ed)
Definition from: MeSH via Unified Medical Language System at the National Library of Medicine
- Cancer that begins in the skin or in tissues that line or cover internal organs.
Definition from: Physician Data Query via Unified Medical Language System at the National Library of Medicine
See also Understanding Medical Terminology.