I don't like X, and it is growing = cancer, is the full depth of the analogy. Pretty weak. Unlike cancer, we wouldn't want to eliminate 100% of expenses. Unlike cancer, expenses are necessary for survival. Unlike cancer, it's possible expenses should be growing faster, to fuel growth or whatever - this is the argument that needs to be made. Calling something cancer this loosely, is very close to the annoyance of invoking Hitler so quickly.

"I don't know about all dem der hosting costs you speak of, but I sure as hell don't like that cancer"