Alternative therapies

Most cancer patients try herbs, vitamins, or other untested treatments in search of relief, or even a cure. Now, scientists are figuring out which ones might really work.

By Scott Allen, Boston Globe Staff  |  June 11, 2007

Doctors used to toss cancer treatments like ginseng tea into the category of "unproved remedies" along with faith healing and laetrile, the now-discredited medicine made from apricot pits that can cause severe poisoning. But the medical profession's disdain didn't stop most cancer patients from trying a wide array of these alternative treatments in their desperate hope for a cure, or at least comfort.

Today, scientists are gaining respect for home cancer remedies as carefully designed studies show that some may actually work.

Last week , scientists at major research centers released studies showing that ginseng appears to help patients fight the fatigue that accompanies chemotherapy, while a grain called flaxseed appears to shrink prostate tumors. A third study suggested that ground up shark cartilage -- popularized by the book "Sharks Don't Get Cancer" -- does nothing to help lung cancer patients. But the study's existence underscores the new seriousness about alternative medicine.

"Patients ask me about these things they have snookered away in their purses and pocketbooks: 'Will they help me?' Most of the time, we can't answer," Dr. Bruce D. Cheson , chief of hematology at Georgetown University Hospital in Washington, D.C., said at a Chicago press conference unveiling the studies. He called the research, which he had no role in, "some of the first and most rigorous studies" ever of complementary and alternative cancer treatments, adding, "We take our cancer advances wherever we can get them."

So far, the most persuasive evidence concerns treatments that ease the suffering that goes with cancer -- such as nausea, pain, and anxiety. It's harder to show that alternative treatments attack the disease itself. However, a few researchers have raised intriguing possibilities: a small four-year study at Creighton University in Nebraska last week suggested that taking vitamin D supplements reduced the risk of cancer in older women by up to 60 percent.

Longtime observers of alternative medicine say the most hopeful sign is that leading researchers are moving into the field, applying the same tough standards they would to test conventional medicines. The ginseng, flax, and shark cartilage studies were carried out by researchers at the Mayo Clinic, Duke University Medical Center, and M.D. Anderson Cancer Center, respectively, all considered among the best cancer centers in the country.

"It's refreshing to see institutions that are well respected in the oncology field . . . applying acceptable, high quality, rigorous standards of proof to look at these things as fairly and dispassionately as possible," said Dr. David Eisenberg , director of the Osher Institute at Harvard Medical School and a leader in research to evaluate complementary and alternative medicine. "If you think of oncologists doing studies like this 10 years ago, there were few, if any."

The rising tide of research comes as the number of people dying from cancer is slowly declining, thanks to a big drop in smoking, better screening to catch tumors early, and improvements in treatment such as the availability of Herceptin for breast cancer. Today, two-thirds of those diagnosed with cancer are likely to be alive in five years compared with a 50 percent survival rate in the mid-1970s.

But cancer patients are not willing to rely solely on conventional medical care, turning to alternative treatments -- including dietary supplements, herbal remedies, yoga, and acupuncture -- about twice the rate of the general public, according to the National Center for Health Statistics. A survey of cancer patients in 2000 showed that they don't tell their doctors about half the time.

For oncologists, the pervasive use of unconventional treatments has long been a problem because they can undermine the patient's care. Researchers caution women with breast cancer against taking soy supplements, for example, because they contain isoflavonoids that may partially neutralize the Tamoxifen that helps prevent cancer recurrence.

"Just saying that it's a vitamin or a leafy green something or other doesn't mean it doesn't have potential side effects," said Cheson, speaking at the annual meeting of the American Society of Clinical Oncology.

The National Cancer Institute spends more than $120 million a year supporting studies of complementary and alternative cancer treatments, such as the largest-ever study of prostate cancer prevention, now underway, and the shark cartilage research. Already, agency-funded studies have shown that vitamin E does not protect women against cancer, but a low-fat diet may help women avoid breast cancer recurrence.

However, scientists have struggled to apply scientific methods to a largely unregulated industry when they can't be sure that the ginseng tea on store shelves contained ginseng. In 2002, researchers from the University of California at San Francisco and the Dana-Farber Cancer Institute in Boston suspended a study into a promising herbal prostate cancer treatment called PC-SPES after they discovered the product was contaminated with an artificial estrogen that could have enhanced the anticancer effect.

In the research released last week, scientists took pains to avoid similar pitfalls, obtaining their natural alternatives from reputable suppliers rather than taking it off the shelf. They were also careful to avoid the hyperbole that has so often surrounded alternative cancer treatments. For instance, Debra Barton , lead researcher on the ginseng study at the Mayo Clinic in Minnesota, said she would want a larger study before she would recommend routine use of ginseng to combat fatigue.

Wendy Demark-Wahnefried of Duke University in North Carolina was measured in her conclusions about the role of flaxseed in fighting prostate cancer. Flax, a grain widely used in medieval foods, is unusually high in omega-3 fatty acids and lignans, both believed to have cancer-fighting properties. Her analysis of prostate glands surgically removed from prostate cancer patients showed that the disease was growing 30 to 40 percent more slowly in men who had eaten flax supplements in the weeks before the surgery.

Still, Demark-Wahnefried isn't pushing flax, noting, "This is just the first study."

Researchers will need years to sort out the science behind alternative cancer treatments and to determine what works best -- even then, people will have to be careful to use products that are not contaminated or fraudulent.

But patients already can bank on a few nondrug options: exercise, massage, and acupuncture relieve many of the physical and psychological stresses of cancer and its treatment. Dr. Glen Aukerman , director for the Center for Integrative Medicine at Ohio State University, said certain nutrients such as omega-3 fatty acids almost certainly help fight off cancer.

But cancer patients need to tell their doctors which complementary and alternative treatments they are following, Harvard's Eisenberg said. "Don't ask and don't tell is an era that we would want to see behind us."