I hate that you have to wait all weekend to get more answers from your doctor. I can translate a bit, but remember, it is not always going to turn out to be metastasis even though it is suspicious. Your doctor will know more and may order another type of scan to be sure what is going on.
A lytic lesion is essentially a hole in the bone. In the 4th lumbar vertebrae of the spine. Which is suspicious for cancer.
I can’t really tell you any more because all I can do really is translate terms for you.
You said you were in recovery after a recurrence, how long ago did you complete treatments? Did they give you a her2 targeted treatment?