NEW YORK (CBSNewYork) — Cancer researchers often test drugs on animals, but mice aren’t the same as people.

What if doctors could test drugs on human cancers that aren’t actually in people?

As CBS2’s Dr. Max Gomez explained, cancer avatars are being created to do just that.

It was during training for a long distance charity bike trek that Kathi Schroeder started struggling to breathe.

“That was part of my clue that something is wrong. You’re not going to jump to cancer,” she said.

It turned out, it was cancer — stage 4 ovarian cancer.

“So far, I’m considered NED, no evidence of disease, which is the best you can get at this point,” she said.

Kathi knows there’s a good chance her cancer will return and that the same treatment may not work. She also knows science could change that.

“As a clinician, I have no reliable way to predict which chemotherapy is going to work,” a researcher said.

Researchers at the Mayo Clinic are working to take some of that guesswork out of cancer therapy by creating a so-called cancer avatar.

“We’re essentially creating a version of the patient’s tumor, just in another location, in this case a mouse,” the researcher added.

The key here is the patient’s own tumor in the avatar. Every cancer is different, and so by carefully monitoring which drugs shrink the cancer in the animal they have a good idea what will work should it return in the patient.

“Perhaps we can predict which therapies will work best for the patient, and spare her the side effects and lost time of ineffective therapies,” the researcher explained.

Rene Maleski is two years into her survival story. She was just the second patient in the country to have her tumor turned into an avatar.

“This avatar thing is hopeful because they’re not just practicing on any cancer, they’re practicing on my cancer, my tumor, what responds,” she said.

Schroeder knows she’s facing an uncertain future, but the avatar gives her hope.

“This probably will happen eventually, but I have options,” she said.

The other important concept is that no two cancers are the same, even if they develop in the same organ. Which means that the same drugs that work on one person’s breast cancer may not work on another. That’s why the avatar is valuable, it’s specific to that patient.