About half of health-related HN submissions feature someone willing to throw out wild medical advice. They'll usually double down, too, by linking to a study - a study that neither they, or 99% of commenters, are capable of effectively evaluating.

Treat them the same as you would that one weird guy who tells you that drinking urine will cure everything that ails you.

That's a single in vitro study which represents Lidocaine's well-studied effects on certain kinds of cancers.

Locally-delivered lidocaine to SCC-diseased oral areas and tumorous lymph nodes is totally feasible.

Feasible, maybe. But has it ever been done before? Are you aware of any papers where lidocaine is used as a treatment for solid tumors, and not simply as an analgesic during or following surgery? Studies in humans would be most relevant, but I'd even be interested in rodent studies if lidocaine is used systemically. (i.e. given orally or injected IP/SC/IV. Having researchers inject lidocaine directly into mouse tumors is not terribly relevant to what you were recommending.)

Your post is also mistaken. The study tested "In vivo tumor growth...using a tumor xenograft model."

It's humanized tumors in mice with humanized immune systems. Totally a mouse/rat study.

Don't be the guy who misleads researchers and sick people out of deep ignorance.