SCIENTISTS OFTEN test drugs in mice. Now, some cancer patients are doing the same - with the hope of curing their own disease.

They are paying a private lab to breed mice that carry bits of their own tumors so treatments can be tried first on the customized rodents. The idea is to see which drugs might work best on a specific person's specific cancer.

The mice may help patients make what can be very hard choices under difficult circumstances. Studies can suggest a certain chemotherapy may help, but patients wonder whether it will work for them. Often there's more than one choice, and if the first one fails, a patient may be too sick to try another. So hundreds of people have made "mouse avatars" over the past few years to test chemotherapies.

"What I'm doing is personalized cancer treatment. It's the wave of the future," said Eileen Youtie, a Miami woman using mice to guide care for her hard-to-treat form of breast cancer. "Part of this is trying to eliminate chemos that are not going to work on me. I don't want to waste time taking them and poison my body."

But experts say there are no guarantees that mice will help.

There are some early encouraging reports. One study of 70 patients found the mice generally reflected how well patients responded to various drugs. But there is no evidence that using mice is any better than care based on medical guidelines or the gene tests that many patients get now to help pick drugs.

Mouse testing costs $10,000 or more, and insurers don't cover it. It takes several months, so patients usually have to start therapy before mouse results are in.

- Associated Press