'The Lance Effect': Does Heat Cure Cancer?

July 25, 2006 — -- Many people have wondered how Lance Armstrong was able to win the Tour de France multiple times after he was treated for testicular cancer that had spread to his lungs and his brain.

As it turns out, medical researchers at Johns Hopkins University have thought about the same thing: Why is testicular cancer so treatable when other forms of cancer are not?

It may simply boil down to temperature, researchers speculate. Testicular cells are more sensitive to heat, and this may offer a clue as to why, even with widespread disease, more than 70 percent of testicular cancer patients survive. Meanwhile, five-year survival rates for people with widespread breast, lung or skin cancers are less than 27 percent, according to statistics from the American Cancer Society.

Testicles are naturally a few degrees cooler than the rest of the body, and when at a normal body temperature, the cells tend to die, said Robert Getzenberg, a cancer researcher and director of urology research at Johns Hopkins University. In a commentary published today in the Journal of the American Medical Association, Getzenberg explains how heat, or hyperthemia, may be used to treat cancers.

He and two co-authors write that metastatic testicular cancer cells -- or those that have spread beyond the testicle to other parts of the body -- also may be weakened by the body's slightly higher temperature. When weakened, the testicular cancer cells are more readily destroyed by radiation and chemotherapy, they wrote, coining the theory the "Lance Armstrong Effect."

Some oncologists say, however, the researchers ideas do not directly relate to Lance Armstrong and why he survived testicular cancer. After all, Armstrong's treatment for testicular cancer involved chemotherapy and surgery. So, the theory could have been named after any other survivor of testicular cancer as well some said.

Nor is it necessarily a new theory, doctors noted.

"We've known for a long time that heating cancer cells kills them," said Dr. Donald L. Trump, an oncologist and senior vice president of clinical research at Roswell Park Cancer Institute in Buffalo, N.Y.

More so, some physicians already use hyperthermia to treat cancer. Dr. Jeffrey Cadeddu, for example, uses radio frequency ablation, a type of hyperthermia, to destroy kidney cancers.

During the procedure, a needle is inserted into the kidney tumor and heat is applied through a special probe. Ablation, so far, has been as effective as surgical removal of the tumor, said Cadeddu, a urologist at the University of Texas Southwestern Medical Center in Dallas. Similar procedures are used for treating lung, bone and breast cancers, he said. Most of this work involves tumors that have not spread.

Getzenberg's research focuses on warming metastatic cancer cells, a therapy that he said has not been used before.

"[Heat sensitivity] may be the leap that we've been looking for," Getzenberg said. Along with two other Hopkins cancer researchers, Donald Coffey and Dr. Theodore DeWeese, Getzenberg has researched whether other cancers are also susceptible to heat.

By using microbeads, or antibodies, to target metastatic cancer cells, doctors could, theoretically, warm the malignant cells using techniques like magnetic resonance. And once the cells are warmed, they are more receptive to chemotherapy and radiation, Getzenberg said. The difference in susceptibility is "night and day," he added.

No one has been treated by this approach yet, he said, although his team has plans to test the therapy.

Some oncologists, however, question the effectiveness of heat to treat cancers.

So far, it's been fairly disappointing as a treatment, said Dr. Derek Raghavan, a specialist in genitourinary cancers and director of the Cleveland Clinic Taussig Cancer Center in Ohio. Raghavan said, high temperatures may actually cause cancers.

Furthermore, Raghavan said no one knows why testicular cancer has such a good prognosis. One reason, he said, could be that testicular cancer cells, unlike other types of cancer cells, do not have "extraction mechanisms," or ways to weaken or remove the cancer drugs used to destroy them. As a result, testicular cancer cells are more easily attacked by the drugs.

Urologist Lindsey Kerr agrees.

"Heat may inhibit or cause cancers to grow," Kerr said. "No one knows the temperature of Lance's testicles."