I believe Keytruda is very dangerous and perhaps other alternatives should be tried first !000mg 95% curcuminoids with black peper extract seems to work.
One such holistic alternative is curcumin. It is water soluble and hard to get to blood stream with oral supplements, so must be taken in high dose concentrated form made bioavailable. 1000 mg 95% curcuminoids with black pepper extract extract taken every 4-5 hours works well. Although many medical studies support this, the medical community does not appear to be well informed of it yet,
https://onlinelibrary.wiley.com/doi/10.1002/cbf.3824?af=R#:~:text=Curcumin%20treatment%20inhibited%20proliferation%20and,also%20reduced%20the%20MMP2%20activity.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8980239/
https://www.frontiersin.org/articles/10.3389/fphar.2021.668567/full
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8307022/
https://www.mdpi.com/1422-0067/23/22/14058
https://onlinelibrary.wiley.com/doi/full/10.1111/bcpt.13648
https://celldiv.biomedcentral.com/articles/10.1186/1747-1028-3-14
https://www.dovepress.com/role-of-curcumin-in-regulating-p53-in-breast-cancer-an-overview-of-the-peer-reviewed-fulltext-article-BCTT
https://www.sciencedirect.com/science/article/pii/S0223523419306361
https://www.reviewscout.org/top-5-turmeric/