癌症患者是否可以服用西洋參或人參?

            筆者在癌症治療與康複谘詢過程中, 經常有華裔癌症患者或家屬向筆者詢問，癌症病人是否可以服用人參、西洋參及其相關製劑?

          這個看似簡單的問題,其實回答起來非常困難,原因是目前許多人參及西洋參相關臨床研究及基礎實驗均有相當不完善的地方,許多結果“似是而非”，再加上中醫界對此也有許多分歧,比如有些中醫師認為不適當的使用人參反而會促進癌細胞的生長,但也有主張可以使用,但要辯證論治,用到恰到好處,這樣病人才會受益!另外，在海外的許多華人治療癌症主要采用西醫的治療手段，幾乎所有癌症專家都反對在化療期間使用各種中草藥，因此許多華裔病人都或多或少地暗自使用中醫中藥，一方麵是他們相信中醫中藥，另外一方麵也是病人有病“亂投醫”的結果。
         
         今天偶然發現在ASCO 年會上發表的一篇關於西洋參用於癌症病人的臨床觀察，他們經初步試驗發現，西洋參有助癌症患者緩解疲勞感。研究人員選取了２８２名患有各種類型癌症的患者，並將他們隨機分為４組：安慰劑組、每日７５０毫克西洋參治療組、每日１０００毫克組和每日２０００毫克組。在試驗開始後第４周和第８周時，研究人員發現，與７５０毫克西洋參治療組和安慰劑組相比，１０００毫克組中２５％的人和２０００毫克組中２７％的人都說，他們的疲勞感“有一定程度緩解”或者“大大降低”，而７５０毫克組和安慰劑組大概隻有１０％的人認為其疲勞感有所降低。
     
     這篇報道可能對華人患者決定是否用西洋參用於癌症治療與康複有一定的指導作用，但這僅是初步研究結果，還不能得出最後的結論，需要繼續大量的臨床實驗。
    
     原文如下!!!!!

 

Flaxseed, Ginseng Show Promise for Cancer Patients

But Shark Cartilage No Help, Study Shows 

 Yahoo! Health: Cancer News

Flaxseed and ginseng appear to be useful for certain cancer patients and should be studied further, researchers said Saturday at the annual meeting of the American Society of Clinical Oncology. Shark cartilage, however, did not appear to hold any benefits.

Three studies discussed during a press briefing are some of the first and most rigorous to evaluate complementary and alternative cancer therapies, said Bruce Cheson, MD, director of hematology services at Georgetown University's Lombardi Comprehensive Cancer Center and moderator of the briefing. Such studies are crucial, he noted, because patients are very interested in these kinds of therapies.

"One of the most common questions my patients ask me is about these things that they have snookered away in their purses or pocketbooks," Cheson told reporters. "They pull out a whole big bag of things and say 'Can I take this? Is this going to help me? Is this going to stop it from coming back?' and most of the time we can't answer because we haven't done the appropriate clinical studies."

The new research brings scientists a step closer to having some answers. And in two cases, the news looks good.

The researchers cautioned, however, that the compounds used in their studies were pure -- which might not be the case for supplements bought in a grocery or health food store.

"It's just not a good idea to grab the nearest bottle on the supermarket shelf," said Debra Barton, PhD, a registered nurse at the Mayo Clinic in Rochester, Minnesota, and the lead investigator of the ginseng study. "Because there is less federal regulation of dietary supplements, there is no consistency in currently available products. In fact, some research has shown various supplements contain little or no amount of the ingredient on the label, and sometimes even harmful contaminants."

Ginseng May Fight Fatigue

Barton's study suggests American ginseng may help fight cancer-related fatigue, a problem that touches some 90% of patients. Exercise is the only remedy that has been shown to help so far, "so other treatments are needed," she noted.

In her study, 282 people were randomly assigned to take 750 mg, 1,000 mg, or 2,000 mg doses of Wisconsin ginseng or a placebo for 8 weeks. The patients answered questionnaires about their energy level and well-being, as well as side effects.

After the 8 weeks, people on placebo and on the lowest dose of ginseng showed similar levels of improvement in energy level and physical well-being, while people taking higher ginseng doses showed greater improvements. People taking 1,000 mg per day had the biggest gains: an increase of more than 14 points (on a scale of 1-100 points) in energy level, and more than 12 points in physical well-being. 

Twice as many people taking the 2 higher doses of ginseng said their fatigue was moderately or very much improved. There were no reported problems with side effects like nausea or sleeping problems.

The findings are so promising, Barton said she and her team are planning a new clinical trial next year to confirm and refine these results.

Flaxseed May Slow Prostate Cancer

In another promising finding presented Saturday, researchers from Duke University showed that flaxseed may slow the growth of prostate tumors. The study involved about 160 men with prostate cancer who were planning to have surgery as treatment.

About a month before surgery, the men were randomly assigned to one of 4 groups: one group took 30 grams of flaxseed (about 3 rounded tablespoons) every day; another took the same amount of flaxseed and followed a low-fat diet; a third group followed only a low-fat diet without taking flaxseed; and the fourth group made no changes in their diet or supplement use. Men who took flaxseed used a ground form that they could mix into drinks or sprinkle on food.

After surgery, the researchers examined each man's prostate tumor. In the men who had been taking flaxseed, with or without the low-fat diet, the cancer cells were dividing more slowly, suggesting slower tumor growth.

Lead researcher Wendy Demark-Wahnefried, PhD, said previous studies of flaxseed and a low-fat diet have shown good results in prostate cancer, but researchers weren't sure if the benefits came from the diet, the flaxseed, or both.

"The [new] results showed that the men who took just flaxseed as well as those who took flaxseed combined with a low-fat diet did the best, indicating that it is the flaxseed which is making the difference," she said.

"These results demonstrate that flaxseed may well protect against prostate cancer growth," she added. "But this is just the first study. We will need to replicate these results before we can make recommendations."

Shark Cartilage a Bust for Lung Cancer

The news was not so good for a form of shark cartilage, however. Researchers from the University of Texas M.D. Anderson Cancer Center showed that it did nothing to improve survival of people with stage 3 non-small cell lung cancer who were also being treated with chemotherapy and radiation.

The researchers used a purified form of shark cartilage derived from dogfish sharks called AE-941 (Neovastat). In lab studies, shark cartilage appears to inhibit blood vessel growth in tumors, and earlier, smaller studies in lung cancer patients suggested those who got high doses of the stuff lived longer than expected with only a few mild side effects (nausea, vomiting, diarrhea).

But in this larger, phase 3 study, those results didn't hold up. Patients were randomly assigned to get 4 ounces a day of either shark cartilage extract or a placebo along with standard chemotherapy and chest radiation.

Those on shark cartilage survived about 14 months, while those on placebo lived an average of about 15 months -- a difference that was not statistically significant.

This is the first large phase 3 trial of shark cartilage in cancer patients, said lead researcher Charles Lu, MD. Smaller studies, however, have also shown no benefit from other forms of shark cartilage.

"We have absolutely no data showing improvements in survival, tumor shrinkage and/or clinical benefits to patients," said Lu. "Now when patients ask their oncologists about shark cartilage, physicians can point to this large NCI-sponsored phase 3 trial and tell patients that, at this point, the only studies that have been done with cartilage-derived products have been negative."

Citations: "A pilot, multi-dose, placebo-controlled evaluation of American ginseng (panax quinquefolius) to improve cancer-related fatigue: NCCTG trial N03CA." Presented June 3, 2007, at the annual meeting of the American Society of Clinical Oncology. First author: Debra L. Barton, PhD, Mayo Clinic, Rochester, Minn.

"Impact of flaxseed supplementation and dietary fat restriction on prostate cancer proliferation and other biomarkers: Results of a Phase II randomized controlled trial using a presurgical model." Presented June 3, 2007, at the annual meeting of the American Society of Clinical Oncology. First author: Stephen L. George, PhD, Duke University.

"A Phase III st udy of AE-941 with induction chemotherapy and concomitant chemoradiotherapy for stage III non-small cell lung cancer." Presented June 2, 2007, at the annual meeting of the American Society of Clinical Oncology. First author: Charles Lu, MD, The University of Texas M.D. Anderson Cancer Center.