In my opinion, anything that lowers blood glucose is going to help cancer survival rates[1].
My father died of pancreatic cancer and both me and my sister-in-law who was a oncology nurse were frustrated with them, wanting to keep him eating those gross protein shakes that were filled with sugar.
[1] https://link.springer.com/article/10.1186/s12889-024-19545-z
I think you are right. Fasting and low sugar diets should also help.
There are some really good studies showing this. Dr. Walter Longo has been doing a study at USC for breast cancer patients. While his protocol is based on fasting, he believes a big reason for its success is the lower glucose.