When considering complementary or alternative treatments, be open-minded yet skeptical. Learn about the potential benefits and risks.

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To help with your research, I found this article by a radiation oncologist who practising integrated cancer care in Australia. In particular, I think you may appreciate the studies she cites.
– Supplemental Mushrooms https://www.drcarolhaddad.com/blog/supplemental-mushrooms

One of my favorite websites for finding evidence-based info about herbs and supplements is Memorial Sloan Kettering Cancer Center (MSK) complementary therapies database:
– Search About Herbs (cancer specific) https://www.mskcc.org/cancer-care/diagnosis-treatment/symptom-management/integrative-medicine/herbs/search

Here's what they have on Chaga Mushroom https://www.mskcc.org/cancer-care/integrative-medicine/herbs/chaga-mushroom

You can also look up the other herbs and supplements you mention to check the validity of the claims and current available evidence.

Keep in mind that natural substances can also have toxicities, adverse side effects and treatment interactions.

Luckily, more and more cancer centers and oncology specialists are open to discussing and integrating complementary medicine. I hope your oncologist is someone with whom you can speak openly about your interest and use of integrative and complementary medicine. Does your cancer center have a integrative medicine department?