I heard that flaxseed and ginseng benefit cancer patients. If so, how should they be used?

Two studies presented at the 2007 meeting of the American Society of Clinical Oncology suggest that flaxseed and ginseng can help patients. Mayo Clinic researchers reported that American ginseng (Panax quinquefolius) eased cancer-related fatigue.

Patients were randomly assigned different doses of ginseng or a placebo for eight weeks. Those on the two highest ginseng doses reported that their fatigue was either moderately or much improved. A study to confirm these results is in the works.

Another study, from Duke University, suggested that flaxseed can slow prostate tumor growth. Flaxseed is an excellent source of alpha-linolenic acid (ALA), the type of omega-3 fatty acid found in plants.

The men who participated in the Duke study were divided into four groups. One group took 30 grams of freshly ground flaxseed daily (about three rounded tablespoons) mixed in drinks or sprinkled on food. The second group took the same amount and went on a low-fat diet. A third group did the diet without flaxseed. And the fourth group made no changes in diet or supplement use.

After surgery, the research team found that cancer cells from the tumors of the men who took flaxseed - whether or not they were on the low-fat diet - were dividing at a slower rate than tumor cells from the other men. These findings must be confirmed by further studies before the details and benefits are fully known.

Men can safely add freshly ground flaxseed to their diets but shouldn't use flaxseed oil, which might increase prostate-cancer risk.

My neurosurgeon has recommended gamma knife surgery for a noncancerous meningioma. I am told that radiation can cause fatigue, and I want to boost my immune system beforehand. What do you recommend?

Gamma knife surgery involves no incisions. The "knife" in question is beams of radiation that doctors can aim with great precision to destroy brain tumors. The radiation doses are so low that the side effects associated with radiation therapy don't occur.

Meningiomas are tumors that develop from the meninges, the membranes that cover the brain and spinal cord. Most are benign and slow growing, but they can lead to symptoms as subtle as memory loss and balance problems, or as dramatic as headaches, seizures, loss of motor function and blindness.

In 90 to 95 percent of all gamma knife procedures, the treated tumors stop growing, and in the majority of all cases, actually shrink. The radiation damages tumor cell DNA, causing cells to die when they try to divide.

To boost your immune system prior to treatment, consult a practitioner of traditional Chinese medicine for an herbal formula called "radio support" for patients undergoing radiation therapy.

You can also take astragalus (Astragalus membranaceous), the root of a plant native to China. Look for astragalus products standardized to 16 percent polysaccharides.