I was wearing tape for sure, maybe a little glue. Clips could be bad (along with any other sort of metal, dentures, crowns, rings, etc). There are a lot of nerves around those nodes and they use a nerve stimulator during the procedure (essentially delivering small electrical shocks to make sure the nerves are OK) and metal could interfere. They also may use electro-cautery to seal off bleeding vessels, which also involves an electrical charge. You'd be surprised how upset people get when they have to remove body piercings for surgery.
Tape and glue should be fine.
Don't stress over the surgery. You'll wake up not even realizing it's over. Hope the biopsy turns out well for you.
--CS