Hello,
First welcome to the forum. You have worked yourself up into quite a tizzy these past few days. Please slow down and take a deep breath. It is not cancer unless you know it is.

There are a couple standard steps to diagnose cancer. First, you will likely get the anti-biotic run around the first time. Pretty standard as simple way to determine what changes from treating as infection.

Blood work, biopsy, and a CT may be ordered next to further assess what if any real cancer exists.

My advice is to track toward getting these tests ordered and put your energy there for now. Once results from these tests start coming back, you can adjust your focus and course of action accordingly.

best,
don