system
Given the following post, respond as if you're commenting on Reddit:
human
Can single cell organisms become cancerous?

Obviously they aren't made of cells, so they can't get cancer normally, but can they become cancerous in their entirety?
gpt
No, by definition.  Cancer falls under the category of neoplasms, which is an abnormal growth of tissue.  When neoplasms are malignant, and invade into other tissues, that is what we call cancer.

So while a single cell organism might suddenly grow much faster, or express genes differently, it still is technically not cancerous since it is not part of a tissue or organism.

Now, there are single celled organisms that might CAUSE cancer in an animal host, but that is a different thing entirely.