Scientifically, ivermectin is suspected to be able to reduce solid cancer tumours and potentially metastasized leukemia, but this last one is based on studies in mice, from what I could find.

There are some studies in human cells to see if this drug could be useful to shrink tumours, but human cells are not humans. Many substances showing promise in cells did not show same success in vivo. And most studies explored solid cancers, tumours, not blood cancers.
There is a phase IIa trial for metastatic triple negative breast cancer in combination with pembrolizumab. There are no results yet that I could find.

As far as I could find, there is no scientifically supported protocol for using those two drugs you mention for any cancer treatment and thus they are not even considered, let alone approved for treatment. Phase II trials means something is just starting to be tested in the target population. IIa means they still need to test which is the right dose.

MPNs are quite different from solid tumour cancers and unless they tranform into AML, they do not metastasize, they do not spread to other parts of the body. So it doesn't enter in the suspected potential of ivermectin.

If you were thinking about another cancer, other than MPN, then that answer should come from an oncologist. Cancers are very different and they would know best.

The case spreading on social media was of someone who actually got the adequate cancer treatment, immunotherapy, then also took fenben as prescribed by social media advice, did not tell their oncologist, and they ended up with severe liver injury from fenben, which also did not help in their cancer treatment.

https://news.cancerconnect.com/treatment-care/f...

Most people, especially adults, in developed countries who wash their hands and are good with hygiene do not have a parasitic infection.
Who told you that, in absence of clear evidence that you have an infection with a parasite that could increase your risk for cancer, you need Ivermectin?
Ivermectin is an antiparasitic, not panacea. There is no universal drug that can help with cancer. Each cancer is different, even cancers with the same name differ, and often drugs need to be tailored for said cancer and said patient.
There are some parasitic infections that could increase the risk for cancer. They are rarely present in the US.
"Certain parasitic worms that can live inside the human body can also raise the risk of developing some kinds of cancer. These organisms are not found in the United States, but they can be a concern for people who live in or travel to other parts of the world."

https://www.cancer.org/cancer/risk-prevention/i...

Parasites that Can Lead to Cancer | American Cancer Society

https://www.cancer.org/cancer/risk-prevention/infections/infections-that-can-lead-to-cancer/parasites.html

not that I'm aware of but I suppose everyone does. I was told that a Ivermectin and Fenbendazole protocol might help with cancer.

Tta....Parasitic infections are not what I'm questioning. I'm wondering if anyone has used the protocol for blood cancer treatments. I googled and found links for Ivermectin and fenben.

Do you have a parasitic infection?
I had some intestinal worm I picked up from a visit abroad years ago and I was prescribed something from the same family of drugs as ivermectin. It went OK, got rid of the intestinal worm.