The cancers that involve "lumps" are not swelling, but performing angiogenesis [1]. Not sure about the blood cancers because, well, I'm not an expert, but I believe that all cancers involve unrestricted cell division of some kind, at least some of the time as a result of a DNA or RNA error.

I believe swelling is typically caused by individual cells or tissues (or even pockets in the body) building up fluids of one kind or another. Unfortunately cancer can cause this kind of swelling when your liver and/or kidneys shut down. Source: My mom died of breast cancer, and things were not pleasant near the end.

If OP is talking about systemic inflammation...then there may be a link between the two, but it's certainly not the only cause. [2]

[1] https://en.wikipedia.org/wiki/Angiogenesis

[2] https://en.wikipedia.org/wiki/Systemic_inflammation

Perhaps he means inflammation. Inflammation has been linked to certain types of cancers.