Lump on base of neck near spine

Grrrrr! I found a weird lump last week on the back of my neck at the base, about an inch from my spine. Needless to say I'm scared. It's been four years since my cancer treatment, which only consisted of surgery and radiation. I couldn't tolerate chemo because of the side effects and a pre-existing condition. Same with Tamoxifen. I have an appointment with my oncologist on Monday.

It's probably nothing, since my tumor markers were checked three months ago and were normal, but still. Grrrrr.

Have any of you ever heard of BC mets to the back of the neck? I'm not talking the lymph node areas, either.

Thank you!