Cancer and Tumor Terms

Cancer types, tumors, staging language, and concepts used in oncology. Browse definitions and meanings below.

434 terms

What is oncology?

Oncology is the branch of medicine concerned with the prevention, diagnosis and treatment of cancer. Its vocabulary describes what a growth is made of, how far it has spread, and how it responds over time.

Several distinctions in this vocabulary carry real weight. Benign and malignant describe how a growth behaves rather than how large it is, and staging and grading measure different things: how far a cancer has spread, and how abnormal its cells look under a microscope.

Terms in this topic

Alphabetical order

For learning, not diagnosis. This glossary provides general educational information and is not a substitute for advice from a qualified healthcare professional. If you may be experiencing a medical emergency, contact local emergency services.