Chemotherapy Biotherapy Certification ONS Practice Testq

What unique characteristic do nitrosoureas possess regarding their ability to treat brain tumors?

1. They can be administered orally

2. They are non-cytotoxic

3. They can cross the blood-brain barrier

4. They are specific for lymphatic cancers

The correct answer is: They can cross the blood-brain barrier

Nitrosoureas are distinctive for their ability to cross the blood-brain barrier, which makes them particularly effective in treating brain tumors. This characteristic is crucial because many chemotherapeutic agents are not able to penetrate this barrier due to its protective nature, which can limit the efficacy of treatments for central nervous system malignancies. The ability of nitrosoureas, such as carmustine (BCNU) and lomustine (CCNU), to traverse this barrier allows them to reach therapeutic concentrations in the brain, targeting the tumor cells more effectively. The other options represent important but less relevant attributes. While some nitrosoureas can be administered orally, their oral bioavailability varies, and this capability does not inherently relate to treating brain tumors. The notion that nitrosoureas are non-cytotoxic or specific for lymphatic cancers is also misleading, as these agents are indeed cytotoxic and are primarily used for treating a range of cancers, including those of the central nervous system rather than being specific to lymphatic cancers.