NCI Dictionary of Cancer Terms
The NCI Dictionary of Cancer Terms features 7,800 terms related to cancer and medicine.
Browse the dictionary by selecting a letter of the alphabet or by entering a cancer-related word or phrase in the search box.
- listen (seh-MUS-teen)
- A substance that has been studied in the treatment of some types of cancer. Semustine damages the cell’s DNA and may kill cancer cells. It is a type of alkylating agent and a type of nitrosourea.