New medical technology could bolster chemotherapy

LIVERMORE, CA -- Chemotherapy helps save the lives of thousands of cancer patients each year. But now, researchers at the Lawrence Livermore Lab and UC Davis believe they've developed a technology that could make chemo treatments even more effective.

Theresa Madsen had just settled into retirement, when she received a frightening diagnosis.

"The CT scan showed I had a tumor on my left kidney," Madsen recalled.

Madsen turned to Dr. Chong-Xian Pan and his team at UC Davis, who first removed her left kidney. Pan then recommended chemotherapy, even though he says the effectiveness can vary wildly from patient to patient.

"For example in lung cancer, chemotherapy only works in less than 30 percent of patients. In bladder cancer, maybe 50 percent respond to chemotherapy," Pan said.

To help boost those odds, Pan is trying an experimental and potentially groundbreaking technique, giving patients a tiny micro-dose of the cancer drug before treatment to gauge its effectiveness.

"This technology is to identify which cancer patients may respond to chemo before they receive chemotherapy," he explained.

That kind of drug screening test may sound simple, but the technology needed to make it work is incredibly powerful; so powerful in fact, that it used to take up a room the size of a warehouse.

The test was developed using a device known as an accelerator mass spectrometer, housed at the Lawrence Livermore Lab. Using the huge unit, scientists can analyze tiny chemical reactions on the scale of DNA. But to make that power practical for cancer treatment, a team at Livermore miniaturized the process, with the goal of analyzing blood samples in a fraction of the time.

Biomedical scientist Mike Malfatti, Ph.D., says common chemotherapy drugs work by binding to the DNA of rapidly dividing cells and killing them. The better a drug binds to a particular patient's DNA, the higher the likelihood it will work. To get that snapshot, technicians tag a tiny dose of the cancer drug with a kind of chemical label that can be measured using the mass spectrometer.

"And with this micro-dose, we can go in and assess how well this drug is going to bind to an individual's DNA," Malfatti said.

Early trials are providing data as proof of concept, according to co-developer Paul Henderson, Ph.D. now with UC Davis. He said, "What we are seeing is a trend of higher DNA damage [that] correlates to patients who respond to chemotherapy."

If the trial is successful, researchers believe the test could eventually be used for almost any of kind of tumor, potentially allowing doctors to save precious time by avoiding chemo drugs that won't work and move to more effective alternatives.

"In the future, if we can identify multiple chemo sensitivities, we might be able to go directly to those effective medications," Pan said.

Madsen completed her chemotherapy and says she's now looking forward to the things she enjoys the most.

"Just to go camping with my husband and my dog, and see God's country," Madsen said.

If successful, developers envision centralized diagnostic centers, which could analyze blood samples sent from regional cancer centers around the country.

Written and produced by Tim Didion