Which statement accurately describes DNA-binding antineoplastic agents in the context of extravasation?

• A. They remain only at the injection site, limiting damage.
• B. They attach to DNA nucleic acids and can cause progressive tissue destruction.
• C. They are the same as non-DNA-binding agents in how they cause tissue injury.
• D. They never cause tissue damage if extravasated.

Answer: (B)

DNA-binding antineoplastic agents cause tissue injury by attaching to DNA in local cells, forming crosslinks or causing breaks that disrupt replication and transcription. When such drugs extravasate, they stay active in the surrounding tissue and continually bind DNA, leading to ongoing cell death and progressive tissue destruction. This explains why the injury can worsen over time if not treated promptly, and it also underpins the rationale for specific antidotes and rapid decontamination strategies.

The idea that these drugs remain confined to the injection site is incorrect because they can diffuse into surrounding tissue and keep causing damage as long as the drug remains in situ. It’s also incorrect to say they are the same as non-DNA-binding agents in the way they injure tissue, since the mechanism—direct DNA interaction and sustained cytotoxicity—drives a different pattern and severity of injury. And they can indeed cause tissue damage if extravasated, so the statement that they never cause damage is false.