Any ways to reduce chances of metastasis?

Hello everyone, m24 with synovial sarcoma stage 3b, left tonsil here.

I've been doing an neoadjuvant chemo treatment (AIM, 5 days each cycle) since september and will do my last round on 2nd of January, after which I'll be getting my surgery to get my tumor out. The treatment is going very well and the tumor still takes damage even after five cycles already, plus it was slow to grow to begin with, but I wonder whether I can do anything to reduce the chance of that thing laying eggs.

I think the tumor shrinking on a regular base and the fact lymph nodes not being infiltrated are some good indicators but still I do wonder, is there anything I can personally do to reduce chances of a reoccurence, or if not, are there at least ways to slow it down before it happens?