The majority of cancer patients who receive chemotherapy and / or radiotherapy tend to experience a basket of symptoms secondary to the disease process or the treatment itself. The most common and burdensome symptoms for these patients is fatigue. Will exercise help in reducing the feeling of fatigue?

Researchers from the University of Copenhagen studied the effect of a supervised exercise program on fatigue in 235 cancer patients who were receiving treatment for solid and haematological tumours (BMJ 2009; 339: b3410). These patients were randomly assigned to the intervention group (n=118) or control group (n=117). The control group received usual medical care and was permitted to increase physical activity as they desired. The intervention group, supervised by trained nurses and physiotherapists, undertook high-intensity exercise training on Mondays, Wednesdays and Fridays and low-intensity exercise on Tuesdays and Thursdays for 6 weeks. Each week they received 9 hours of intervention in groups of 7 to 10. High-intensity exercise consisted of 30 minutes of warm-up, 45 minutes of resistance training and 15 minutes of cardiovascular training. Low-intensity training consisted of relaxation for 30 minutes weekly, body awareness and restorative training for 90 minutes weekly and massage for 30 minutes weekly. The study found that, in the intervention group, there was a significant reduction of fatigue. The patients also showed significant improvement on 7 of 10 Short Form-36 subscales on general well-being, physical functioning, vitality, mental health, physical and mental components scale. The leisure time physical activity was 66% in the intervention group compared to 33% in the control group. In the intervention group, muscle strength improved 29.6%. The researchers concluded that a structured exercise program improved fatigue and physical and mental functioning among patients with advanced cancer who were receiving chemotherapy.

Quite often my cancer patients will ask if they should exercise. However, family members tend to discourage the patient because they fear exercise will make the patient even more tired. Whenever I am asked if a patient should exercise, my answer is invariably yes.  Yes because physical activity will not only make the patients get out of the house but also will help take their mind off their condition.

Next time, when your loved one who is undergoing chemotherapy / radiotherapy wants to go for a walk, try saying ‘Yes, lets.’

Long-term exposure to low-dose ionising radiation has been linked to the development of solid cancers and leukaemia. Consequently, workers in the healthcare sector and in the nuclear industry who are at risk for repeated radiation exposure have to be monitored. They are limited to an effective radiation dose of 100 mSv every 5 years, with a maximum of 50 mSv allowed in any given year. With the increasing use of radiological scanning in the general population, patients are not monitored for their overall exposure to ionising radiation and there is little information on the subject.

Researchers from Emory University recently conducted a study on 655,613 enrollees, aged 18 – 64 years, from 5 healthcare markets: Arizona; Dallas; Orlando, Florida; South Florida and Wisconsin (N Engl J Med 2009; 361: 849 – 857). The amount of radiation exposure to each patient over the period January 1 2005 to December 31 2007 was noted. The mean cumulative effective dose of radiation exposure from imaging procedures was 2.4 +/- 6.0 mSv per person per year. Women underwent significantly more imaging procedures than men; 78.7 % of women undergoing at least one procedure during the 3 year period as compared to 57.9% of men. The proportion of enrollees undergoing at least one procedure during the 3 year period increased with age as well: 49.5% aged 18 – 34 years versus 85.9% aged 60 – 64 years. While most of the patients studied had low exposure (≤ 3 mSv per year, equivalent to the background level of radiation from natural sources in the United States), not an insignificant number of enrollees were exposed to higher radiation doses. Moderate annual effective doses (> 3 – 20 mSv) were incurred at an annual rate of 193.8 / 1000 enrollees, while 18.6 / 1000 enrollees and 1.9 / 1000 enrollees had high (> 20 – 50 mSv) and very high (> 50 mSv) exposure, respectively. The top 5 imaging procedures with the largest contributions to the cumulative effective radiation dose were myocardial perfusion scanning (22.1%), CT of the abdomen (18.3%), CT of the pelvis (12.2%), CT of the chest (7.5%) and diagnostic cardiac catheterization (4.6%). From this study, it was estimated that approximately 4 million non-elderly adult Americans would be receiving > 20 mSv per year from imaging procedures.

Part of the reason why Joe Public requests various imaging procedures during health checks is the perception that, if the various scans are normal, he is safe and free of cancer. He is only safe at that point in time. There is no guarantee that a small cancer is already lurking somewhere in the body. The scan could not demonstrate it because it was too small for the machine to ‘see’. Furthermore, there is no stopping a new cancer from developing 3 months after the scanning procedures. Imaging procedures should be ordered and used judiciously. While the doctor looking after the patient has a duty not to over-investigate, the patient must also refrain from pressurizing the doctor into doing a scan just because the patient saw a health report on TV about how powerful XYZ scan is in detecting cancer of the little toe!

At the 7th Annual American Association for Cancer Research International Conference on Frontiers in Cancer Prevention Research (AACR FCPR 2008) held last week in Washington, D.C, several papers were presented on the role of vitamin supplementation in the prevention of cancers.

Researchers from Harvard University studied the potential benefits of vitamins E and C supplements on 14,461 male physicians, 50 years or older, who participated in the Physicians’ Health Study II. Participants were given 400 IU of vitamin E every other day or placebo and 500 mg of vitamin C daily or placebo. They were followed for a mean of 8 years. After 8 years, taking vitamin E supplements had no effect on the incidence of prostate cancer. Vitamin C supplementation had no effect on total cancers or on specific cancers such as colorectal, lung or prostate.   

In another study, the Calcium Polyp Prevention Study, from the Vanderbilt University, 930 men were randomized to receive placebo or calcium supplementation (1,000 mg daily for 4 years) to see if calcium supplementation could prevent colorectal adenoma recurrence. (Colorectal adenomas are precursors to colorectal cancers.) The researchers found that calcium supplementation only reduced polyp recurrence in people whose dietary ratio of calcium to magnesium intake was low before treatment and remained low during treatment. Among those with baseline calcium to magnesium ratio below the median, calcium supplementation reduced the risk of adenoma recurrence by 32%.  

In a separate published study from the Harbor-UCLA Medical Center, 36,282 postmenopausal women, who were enrolled in a Women’s Health Initiative clinical trial, were randomly assigned to 1000mg of elemental calcium with 400 IU of vitamin D3 daily or placebo for a mean of 7 years (J Natl Cancer Inst 2008; 100: 1581 – 1591). This study was carried out to look at the effects of supplement use on the incidence of hip fracture with incidence of invasive breast cancer as a secondary outcome. At the end of the study period, the incidence of invasive breast cancer in postmenopausal women was not affected by calcium and vitamin D supplementation.

An interesting study on the protective effects of consuming cruciferous vegetables in smokers was presented at the AACR FPCR 2008. Researchers from Roswell Park Cancer Institute in Buffalo, New York, studied 948 patients diagnosed with primary lung cancer and 1743 healthy controls between 1982 and 1998. The researchers found that there was a strong linear inverse association between intakes of fruit, total vegetables and cruciferous vegetables and the risk for lung cancer (odds ratio range 0.53 – 0.70). The study results suggest that the risk of developing lung cancer among smokers was reduced by 22 – 50 % if they consumed at least 4.5 servings of raw cruciferous vegetables per month compared to those who ate less than 2.5 servings per month. This inverse association of reduced lung cancer was only seen for squamous or small cell cancer, the 2 subtypes of lung cancer most commonly associated with heavy smoking. [The same group of researchers had demonstrated that the intake of raw cruciferous vegetables, including broccoli, broccoli sprouts, cabbage and cauliflower, was associated with a reduced risk for bladder cancer (Cancer Epidemiol Biomarkers Prev 2008; 17: 938 – 944). The protective action of cruciferous vegetables is derived from isothiocyanates, a group of phytochemicals which can be degraded by cooking.]

At present it is reasonable to conclude that supplementing with individual vitamins may not be sufficient to prevent cancer. Chemoprevention of cancer probably depends on a combination of vitamins and minerals. As yet we do not posses the knowledge to formulate the correct combination that works. Do multivitamin supplements work better? We do not have the answer yet. What we do know is that Mother Nature has perfected the combination in the form of fruits and vegetables. Seriously, why would you choose to take pills when you can enjoy the taste of fresh fruits and vegetables!