High B12 levels

nume

I had 15 chemo infusions(last one 5 weeks ago), I am preparing for double mastectomy with reconstruction and had blood analysis 10 days prior to surgery.(next week) PET Scan was clean and blood results came two days ago mostly good but I had a very high B12 level of 1335. I got extremely scared reading online what high B12 is associated with.

Anybody knows how to decrease B12 or had similar values at a certain point?

Thank you!