Cancer patients ought to be able to talk openly with their doctors about complementary and alternative medicines (CAMs), but many still do not because of communication barriers, according to a report in Psycho-Oncology (Vol. 11: 212-220).

Doctors need to keep abreast of such therapies, and make sure patients are comfortable enough to discuss them, said the authors. Scientific evidence is not the only thing that matters to someone facing a life-threatening disease, they said.

"It is important for most patients to communicate with their physicians and to have their approval," said Gertraud Maskarinec, MD, PhD, one of the authors, and an associate researcher at the Cancer Research Center of Hawaii in Honolulu. For Maskarinec, that desire for approval was one of the more enlightening aspects of the study.

CAMs include meditation, nutritional supplements, massage, and even prayer.

According to previous studies cited by the article, as many as 50% to 83% of cancer patients reported using at least one type of CAM therapy. Other studies showed 54% to 70% of cancer patients using such therapy did not disclose this to their physicians, the authors said.

"Complementary" therapies are those that are used alongside traditional medical approaches such as surgery, chemotherapy, and radiation therapy. The term "alternative" is usually reserved for those therapies that patients use instead of traditional medicine.

Maskarinec said physicians are more comfortable with some complementary therapies than others, such as vitamins and massage.

But even high doses of vitamins can have an impact on the patient's other therapy, so it's important for patients to tell their doctors what they're taking, said David Rosenthal, MD, a professor of medicine at Harvard Medical School and chairman of the American Cancer Society complementary and alternative methods of cancer management committee.

For example, anti-oxidants may be harmful for patients undergoing radiation therapy, Rosenthal said, and high doses of other supplements can be toxic. A lack of standardized production — meaning the substance in the pill may not be the same in every lot — is yet another problem with some supplements, he said.

But the communication problem is improving, Rosenthal said. More doctors are aware of CAMs. Medical schools such as Harvard now provide courses in "integrative therapies," he said.

"Patients can expect a listening ear, and also a discussion of what is known and what isn't known," Rosenthal said.

A patient-doctor relationship should be based on trust, Rosenthal said. If a patient doesn't feel he or she can trust the doctor, they should look for another.

Maskarinec also said patients should expect a physician to listen, and discuss all aspects of any therapy the patient might want to start.

"My advice is to ask the physician what they think about the CAM that the patient would like to start, so the possibility of side effects can be discussed," she said.

According to the article, patients felt that three barriers emerged to hinder good communication between them and their physicians. Those barriers were:

• Doctors being indifferent or opposed to CAM use.
• Doctors emphasizing the lack of scientific evidence supporting CAM use.
• Patients' anticipation of a negative response from the physician.

In the study, patients often complained that the physician looked only at the scientific evidence, while these patients wanted a more open-minded approach. The challenge, stated the study authors, may be in finding a common ground for discussion.

Rosenthal said that doctors might need to do a better job of educating patients on how scientific research explores cancer therapies.

After all, he said, "Most physicians are teachers."