New Growth on Leg

I'm trying to get information on treating squamous cell carcinoma. I have not had it formally diagnosed, but after researching it on the web, this is more than likely what it is.
The growth sits on top of my upper right tibia. It's attached to the bone and is surrounded by skin graft resulting from a former injury dating back to 1968. It first became noticeable after bumping my leg about five months ago, probably sometime in January. It's about the size of a quarter.
I just turned 72 yrs old, but I am very physically fit and not over weight. I've been on a no sugar (keto), low salt diet for about 3 months now as to the negative aspects of sugar to all types of cancer.
I need some educated advise on how to kill this thing, or at least, slow it down. Due to the current hospital status around the country, a hospital stay is out of the question.
I would very much appreciate hearing from anyone who has successfully experienced battling this problem, either personally, or as a worker in the medical field. Judging from my research, I don't see anything much that I can do, however, I don't believe it's totally impossible either...