Tumor Expert Attacks Government-Sponsored Cancer Test Treatments

A leading tumor specialist has called on the National Cancer Institute to stop testing a novel immune system treatment for advanced cancer patients, citing disappointing response rates, “unacceptably” severe side-effects and “astronomical” costs.

The researcher, Dr. Charles G. Moertel of the Mayo Clinic, said that the experimental treatment has no role in “the compassionate management of patients with cancer.”

His criticisms of the widely publicized “interleukin-2/killer cell” therapy appear in today’s issue of the Journal of the American Medical Assn. They accompany an article on the early results of high-dose interleukin-2 therapy by Dr. Steven A. Rosenberg, chief of surgery at the National Cancer Institute, who pioneered the treatment.

“I disagree completely,” Rosenberg responded in a telephone interview from Bethesda, Md. “This is a very promising therapy which is in the infancy of its development.”

The unusual public debate between Moertel, who has often debunked the high-flying claims of other cancer researchers, and Rosenberg, a highly respected researcher who also performed colon cancer surgery on President Reagan in 1985, adds to the confusion about whether the highly touted therapy is living up to initial expectations.

The treatments use the protein interleukin-2, a natural immune system booster, to transform in the laboratory a patient’s own white blood cells into activated tumor-killing cells, called “LAK” cells. Such cells are then injected into the patient’s bloodstream through a vein, along with massive doses of interleukin-2.

Sometimes, as in Rosenberg’s most recent study, high doses of interleukin-2 are used alone. With this therapy, three of six patients with the malignant skin tumor melanoma had greater than 50% shrinkage of their tumors, according to his article. Other therapies are ineffective against advanced cases of melanoma.

Two of these patients are still living more than a year after receiving the therapy. The other died of the disease seven months after being treated.

High-dose interleukin-2 therapies have been tested so far on more than 100 patients at the Cancer Institute and about 100 patients at six other medical centers, including the City of Hope in Duarte and the University of California, San Francisco. They seem to be most effective for patients with either kidney cancer or melanoma.

The nationwide trials of the therapies, expected to last several years, were temporarily suspended in September because of an unusual outbreak of hepatitis among some of the patients. They are expected to resume by early next year. Trials at the Cancer Institute in Bethesda are continuing.

Moertel was asked to write the editorial after delivering a scathing pre-publication review of Rosenberg’s paper to the medical journal.

Moertel is a former president of the American Society of Clinical Oncology, the leading organization of tumor specialists. In the early 1980s, he organized the government-sponsored study that discredited Laetrile as a cancer cure and challenged the claim by Nobel Prize-winning chemist Linus Pauling that large doses of Vitamin C were useful in treating cancer. He has also sounded warnings about other proposed immunotherapies for cancer, including the drug interferon and an extract made from the tuberculosis bacteria.

Moertel’s editorial points out that high-dose interleukin-2 treatments lead to severe toxic reactions, such as low blood pressure, confusion and retention of excess fluids, and can require weeks of intensive care hospitalization. Costs “may reach six figures,” he said.

Moertel calls for investigators to develop alternate treatments, using lower doses of immune system boosters and perhaps traditional chemotherapy as well, that “will be both practical and tolerable for human use.”

Rosenberg, in response, said researchers are learning how to increase the effectiveness of interleukin-2 treatments and decrease the side-effects. He said costs now average about $10,000 per patient, which is paid by the government.

“I have never called interleukin-2 therapy a breakthrough,” he said. “I have always been incredibly cautious and . . . called it a first step.”