Should doctors prescribe exercise?

“Although the data vary by different cancer types, there is a consistent trend suggesting that moderate daily exercise has a beneficial effect on preventing certain cancers. If you are a reasonably healthy adult, your should exercise regularly.” 

Let’s look at the relationship of exercise and selected cancers. The American Society of Clinical Oncology (ASCO) has done a nice job of summarizing:

Breast Cancer

While the amount of risk reduction varies among studies (20-80%), most suggest that 30 to 60 minutes of moderate to high-intensity exercise per day lowers breast cancer risk. Women who are physically active throughout their life appear to benefit the most, but those who increase physical activity after menopause also fare better than inactive women.1

Colon Cancer

Research suggests that people who increase their physical activity can lower the chance of developing colon cancer by 30 to 40% relative to sedentary adults.1,2 A decrease in colon cancer risk can be achieved regardless of body mass index (BMI) and people who are most active benefit the most. There is insufficient evidence of a protective effect of physical activity on the risk of rectal cancer (a protective effect was seen in some case-control studies, but not in cohort studies).3

Endometrial, Lung and Ovarian Cancer

A handful of studies have suggested that women who are physically active have a 20-40% reduced risk of endometrial cancer compared to those who don’t exercise.1 Higher levels of physical activity seem to also protect against lung cancer (up to 20% reduction in risk), particularly among men.1Although less consistent, research suggests that physical activity possibly reduces the risk of ovarian and prostate cancer.

What about Other Cancers?

While observational data on the benefits of exercise for prevention of the types of cancers listed above are fairly consistent, evidence of the effects of exercise on prevention of any other type of cancer either is either insufficient or inconsistent.2,4

Prostate Cancer

Prostate cancer is one disease in which the data are not consistent, however prostate cancer is a heterogeneous disease and risk factor associations for total non-aggressive disease are different from aggressive / lethal disease. Most population based studies show similar findings, with little effect of exercise on overall incidence of prostate cancer but lower risk of aggressive prostate cancers for those with the highest levels of VIGOROUS activity (rather than any type of activity). In the Health Professionals Follow-up Study men 65 years or older who engaged in vigorous physical activity, such as running, jogging, biking, swimming or tennis at least three hours per week  had a 67% lower risk of advanced prostate cancer and 74% lower risk of fatal prostate cancer.5

Conflicting data for other malignancies

For example, one recent study found no association between physical activity and risk of developing gastric, rectal, pancreatic, bladder, testicular, kidney and hematological cancers.4 In contrast, a pooled analysis of data from prospective trials with 1.4 million participants found that physical activity was linked to lower risk of 13 cancers: esophageal, lung, kidney, gastric, endometrial, myeloid leukemia, myeloma, colon, head and neck, rectal, bladder, and breast.6Interestingly, leisure-time physical activity was associated with a higher risk of melanoma (presumably due to time spent outdoors) and prostate cancer, although it is not clear from these data whether that association was with nonaggressive or aggressive prostate cancer.

While we wait for confirmation and clarity on the role of exercise in preventing all the 200+ types of cancer – should doctors prescribe exercise? The answer is simple: yes, because evidence of the protective role of exercise is already strong for some of the most common cancers.

References

  1. Lee I, Oguma Y. Physical activity. In: Schottenfeld D, Fraumeni JF, editors. Cancer Epidemiology and Prevention. 3rd ed. New York: Oxford University Press, 2006.
  2. Slattery, ML. Physical activity and colorectal cancer. Sports Medicine 2004; 34(4): 239–252.
  3. Pham NM, et al. Physical activity and colorectal cancer risk: an evaluation based on a systematic review of epidemiologic evidence among the Japanese population. Jpn J Clin Oncol. 2012 Jan;42(1):2-13.
  4. Friedenreich CM, Neilson HK, Lynch BM. Eur J Cancer. State of the epidemiological evidence on physical activity and cancer prevention. 2010 Sep;46(14):2593-604.
  5. Giovannucci E, Liu Y, Leitzmann MF, et al. A prospective study of physical activity and incident and fatal prostate cancer. Arch Intern Med. 2005; 165(9):1005-1010.
  6. Moore SC, Lee IM, Weiderpass E, et al. Association of Leisure-Time Physical Activity With Risk of 26 Types of Cancer in 1.44 Million Adults. JAMA Intern Med. 2016 Jun 1;176(6):816-25.
  7. http://www.asco.org/about-asco/press-center/asco-resources-media/cancer-perspectives/should-cancer-doctors-prescribe?et_cid=38723632&et_rid=463715101&linkid=Read+more

I’m Dr. Michael Hunter. Of course, the disclaimer: Do not begin an exercise program without input from an appropriate medical professional. Many can simply start with a brisk walk for 30 minutes daily, 5 days per week. Have a wonderful day!

Should doctors prescribe exercise?

young woman running city park

“Although the data vary by different cancer types, there is a consistent trend suggesting that moderate daily exercise has a beneficial effect on preventing certain cancers. If you are a reasonably healthy adult, your should exercise regularly.” 

Let’s look at the relationship of exercise and selected cancers. The American Society of Clinical Oncology (ASCO) has done a nice job of summarizing:

Breast Cancer

While the amount of risk reduction varies among studies (20-80%), most suggest that 30 to 60 minutes of moderate to high-intensity exercise per day lowers breast cancer risk. Women who are physically active throughout their life appear to benefit the most, but those who increase physical activity after menopause also fare better than inactive women.1

Colon Cancer

Research suggests that people who increase their physical activity can lower the chance of developing colon cancer by 30 to 40% relative to sedentary adults.1,2 A decrease in colon cancer risk can be achieved regardless of body mass index (BMI) and people who are most active benefit the most. There is insufficient evidence of a protective effect of physical activity on the risk of rectal cancer (a protective effect was seen in some case-control studies, but not in cohort studies).3

Endometrial, Lung and Ovarian Cancer

A handful of studies have suggested that women who are physically active have a 20-40% reduced risk of endometrial cancer compared to those who don’t exercise.1 Higher levels of physical activity seem to also protect against lung cancer (up to 20% reduction in risk), particularly among men.1Although less consistent, research suggests that physical activity possibly reduces the risk of ovarian and prostate cancer.

What about Other Cancers?

While observational data on the benefits of exercise for prevention of the types of cancers listed above are fairly consistent, evidence of the effects of exercise on prevention of any other type of cancer either is either insufficient or inconsistent.2,4

Prostate Cancer

Prostate cancer is one disease in which the data are not consistent, however prostate cancer is a heterogeneous disease and risk factor associations for total non-aggressive disease are different from aggressive / lethal disease. Most population based studies show similar findings, with little effect of exercise on overall incidence of prostate cancer but lower risk of aggressive prostate cancers for those with the highest levels of VIGOROUS activity (rather than any type of activity). In the Health Professionals Follow-up Study men 65 years or older who engaged in vigorous physical activity, such as running, jogging, biking, swimming or tennis at least three hours per week  had a 67% lower risk of advanced prostate cancer and 74% lower risk of fatal prostate cancer.5

Conflicting data for other malignancies

For example, one recent study found no association between physical activity and risk of developing gastric, rectal, pancreatic, bladder, testicular, kidney and hematological cancers.4 In contrast, a pooled analysis of data from prospective trials with 1.4 million participants found that physical activity was linked to lower risk of 13 cancers: esophageal, lung, kidney, gastric, endometrial, myeloid leukemia, myeloma, colon, head and neck, rectal, bladder, and breast.6Interestingly, leisure-time physical activity was associated with a higher risk of melanoma (presumably due to time spent outdoors) and prostate cancer, although it is not clear from these data whether that association was with nonaggressive or aggressive prostate cancer.

While we wait for confirmation and clarity on the role of exercise in preventing all the 200+ types of cancer – should doctors prescribe exercise? The answer is simple: yes, because evidence of the protective role of exercise is already strong for some of the most common cancers.

References

  1. Lee I, Oguma Y. Physical activity. In: Schottenfeld D, Fraumeni JF, editors. Cancer Epidemiology and Prevention. 3rd ed. New York: Oxford University Press, 2006.
  2. Slattery, ML. Physical activity and colorectal cancer. Sports Medicine 2004; 34(4): 239–252.
  3. Pham NM, et al. Physical activity and colorectal cancer risk: an evaluation based on a systematic review of epidemiologic evidence among the Japanese population. Jpn J Clin Oncol. 2012 Jan;42(1):2-13.
  4. Friedenreich CM, Neilson HK, Lynch BM. Eur J Cancer. State of the epidemiological evidence on physical activity and cancer prevention. 2010 Sep;46(14):2593-604.
  5. Giovannucci E, Liu Y, Leitzmann MF, et al. A prospective study of physical activity and incident and fatal prostate cancer. Arch Intern Med. 2005; 165(9):1005-1010.
  6. Moore SC, Lee IM, Weiderpass E, et al. Association of Leisure-Time Physical Activity With Risk of 26 Types of Cancer in 1.44 Million Adults. JAMA Intern Med. 2016 Jun 1;176(6):816-25.
  7. http://www.asco.org/about-asco/press-center/asco-resources-media/cancer-perspectives/should-cancer-doctors-prescribe?et_cid=38723632&et_rid=463715101&linkid=Read+more

 

I’m Dr. Michael Hunter. Of course, the disclaimer: Do not begin an exercise program without input from an appropriate medical professional. Many can simply start with a brisk walk for 30 minutes daily, 5 days per week. Have a wonderful day!

Ground-breaking Lung Cancer Breath Test in Clinical Trial

What You Need to Know: Medical researchers are evaluating a revolutionary device which detects lung cancer in early stages by evaluating breath. It is hoped that the LuCID (Lung Cancer Indicator Detection) program will lead to a non-invasive method of diagnosing lung cancer in the early stages.

A clinical trial led by University of Leicester respiratory experts into a potentially ground-breaking ‘breath test’ to detect lung cancer is set to get underway at the Glenfield Hospital in Leicester (England). The device works by measuring volatile organic compounds (VOCs) at low concentrations in a patient’s breath and offers a cheaper and smaller alternative to existing detection technologies.

Study leader Dr Salman Siddiqui offers: “Lung cancer has one of the lowest 5-year survival rates of all cancers, however early diagnosis can greatly improve a patient’s prognosis. Current diagnostic procedures such as a chest X-ray, CT scan and bronchoscopy are costly and not without risks so the benefits of a non-invasive, cheaper alternative are clear.

My Take: Can’t wait. For now, if you have a significant history of cigarette smoking (for example, 1 pack per day for at least 30 years, or 2 ppd for 15 years), ask your health care provider if a screening CT scan might be appropriate for you. I’m Dr. Michael Hunter.

The small print: The material presented herein is informational only, and is not designed to provide specific guidance for an individual. Please check with a valued health care provider with any questions or concerns. As for me, I am a Harvard- , Yale- and UPenn-educated radiation oncologist, and I practice in the Seattle, WA (USA) area. I feel genuinely privileged to be able to share with you. If you enjoyed today’s offering, please consider clicking the follow button at the bottom of this page.

Available now: Understand Colon Cancer in 60 Minutes; Understand Brain Glioma in 60 Minutes. Both can be found at the Apple Ibooks store. Coming Soon for iPad: Understand Breast Cancer in 60 Minutes; Understand Colon Cancer in 60 Minuteable now: Understand Colon Cancer in 60 Minutes; Understand Brain Glioma in 60 Minutes. Thank you.

Reference: University of Leicester. “Ground-breaking lung cancer breath test in clinical trial.” ScienceDaily. ScienceDaily, 14 February 2015. <www.sciencedaily.com/releases/2015/02/150214201621.htm>.

Radiosurgery: Will it Replace Surgery?

What You Need to Know: Stereotactic Body Radiation Therapy (SBRT) is an effective alternative to surgery for medically inoperable aptients with early lung cancer.

What is Radiosurgery? 

The Evidence: The Radiation Therapy Oncology Group (RTOG; USA) 0236 trial enrolled 59 patients with early (T1 and T2) peripheral lung cancer. Here are the results at 3 years:

  • Local tumor control: 97.6%
  • Overall survival 56%
  • Local tumor control, including for the entire lobe: 90.6%
  • Side effects: Grade 3 = 13%; Grade 4 = 3.6%; more patients died of other causes than they did from lung cancer
  • My Take: This provocative study suggests that highly selected patients with early lung cancer may now have an effective, non-invasive management tool. However, we do not have high-level evidence to have it replace surgery. For now, it offers great promise for patients deemed to infirm (medically inoperable) for surgery. Unfortunately only two prospective trials have been reported for operable patients – and remain unpublished.
  • Several randomized studies comparing surgery to stereotactic body radiation therapy (Stereotactic Ablative Body Radiation, or SABR) have close early due to poor accural, including ROSEL (lobectomy vs. SBRT), STARS (lobectomy vs. SBRT with cyberknife), and ACOSOG Z4099/RTOG 1021 (sublobar resection vs. SBRT). I’m Dr. Michael Hunter.
  • Patients with centrally located tumors may be treated effectively with SBRT, but are at higher risk fo side effects. In addition, larger tumors may not have the same high local control rates as do smaller ones.

I’m Dr. Michael Hunter.

The small print: The material presented herein is informational only, and is not designed to provide specific guidance for an individual. Please check with a valued health care provider with any questions or concerns. As for me, I am a Harvard- , Yale- and UPenn-educated radiation oncologist, and I practice in the Seattle, WA (USA) area. I feel genuinely privileged to be able to share with you. If you enjoyed today’s offering, please consider clicking the follow button at the bottom of this page.

Available now: Understand Colon Cancer in 60 Minutes; Understand Brain Glioma in 60 Minutes. Both can be found at the Apple Ibooks store. Coming Soon for iPad: Understand Breast Cancer in 60 Minutes; Understand Colon Cancer in 60 Minute; Understand Colon Cancer in 60 Minutes; Understand Brain Glioma in 60 Minutes. Thank you.

Breath Temperature: Can We Tell if You Have Lung Cancer?

What You Need to Know: The temperature of exhaled breath could be used to diagnose lung cancer. Results of a recent study demonstrate that patients with lung cancer have a higher breath temperature than those without. The temperature also increases with the number of years a person had smoked and the stage of their lung cancer.

Background: Many research teams have been looking at the possibility of using breath tests for a number of cancers. This is the first study looking at breath temperature as a marker in lung cancer.

The Study: The research, presented at the European Respiratory Society (ERS) International Congress in Munich, suggests that testing the temperature of breath could be a simple and noninvasive method to either confirm or reject the presence of lung cancer. The researchers enrolled 82 people in the study who had been referred for a full diagnostic test after an x-ray suggested the presence of lung cancer. 40 patients received a positive diagnosis, while 42 patients had the diagnosis rejected. Researchers measured the temperature of exhaled breath in all patients using a breath thermometer device, known as an X-Halo device.

Results: Patients with lung cancer had a higher breath temperature than those without. Breath temperature also increased with the number of years a person had smoked and the stage at which their lung cancer had developed. The researchers also identified a cut-off value in the measurement of temperature, which they proved could identify lung cancer with a high level of accuracy.

Professor Giovanna Elisiana Carpagnano, lead author of the study from the University of Foggia, Italy, said: “Our results suggest that lung cancer causes an increase in the exhaled temperature. This is a significant finding and could change the way we currently diagnose the disease. If we are able to refine a test to diagnose lung cancer by measuring breath temperature, we will improve the diagnostic process by providing patients with a stress-free and simple test that is also cheaper and less intensive for clinicians.”

My Take: Exciting. But not ready for general use. So: 1) Don’t smoke; 2) If you smoke, quit; 3) if you have a 30 pack-year history of cigarette use (fro example, 1 pack per day for 30 years, or 2 packs per day for 15), ask your healthcare provider whether you may be a candidate for a low-dose screening CT scan. I’m Dr. Michael Hunter.

The small print: The material presented herein is informational only, and is not designed to provide specific guidance for an individual. Please check with a valued health care provider with any questions or concerns. As for me, I am a Harvard- , Yale- and UPenn-educated radiation oncologist, and I practice in the Seattle, WA (USA) area. I feel genuinely privileged to be able to share with you. If you enjoyed today’s offering, please consider clicking the follow button at the bottom of this page.

Available now: Understand Colon Cancer in 60 Minutes; Understand Brain Glioma in 60 Minutes. Both can be found at the Apple Ibooks store. Coming Soon for iPad: Understand Breast Cancer in 60 Minutes; Understand Colon Cancer in 60 Minute; Understand Colon Cancer in 60 Minutes; Understand Brain Glioma in 60 Minutes. Thank you.

Reference: European Lung Foundation. “Breath temperature test could identify lung cancer.” ScienceDaily. ScienceDaily, 8 September 2014. <www.sciencedaily.com/releases/2014/09/140908083738.htm>.

Smell Test May Help Detect Alzheimer’s Dementia

The Evidence: Scientists have found that individuals who are unable to identify certain odors are more likely to experience cognitive impairment. The researchers believe that brain cells crucial to a person’s sense of smell are killed in the early stages of dementia.

Background: The ability to smell is associated with the first cranial nerve, and is often one of the first things to be affected by cognitive decline. There is growing evidence that the decreased ability to correctly identify odors is a predictor of cognitive impairment and an early clinical feature of Alzheimer’s. As the disease begins to kill brain cells, this often includes cells that are important to the sense of smell.

The Study: Matthew E. Growdon, B.A., M.D./M.P.H. candidate at Harvard Medical School and Harvard School of Public Health, and colleagues investigated the associations between sense of smell, memory performance, biomarkers of loss of brain cell function, and amyloid deposition in 215 clinically normal elderly individuals enrolled in the Harvard Aging Brain Study at the Massachusetts General Hospital. The researchers administered the 40-item University of Pennsylvania Smell Identification Test (UPSIT) and a comprehensive battery of cognitive tests. They also measured the size of two brain structures deep in the temporal lobes — the entorhinal cortex and the hippocampus (which are important for memory) — and amyloid deposits in the brain.

Results: Growdon reports that, a smaller hippocampus and a thinner entorhinal cortex were associated with worse smell identification and worse memory. The scientists also found that, in a subgroup of study participants with elevated levels of amyloid in their brain, greater brain cell death, as indicated by a thinner entorhinal cortex, was significantly associated with worse olfactory function — after adjusting for variables including age, gender, and an estimate of cognitive reserve.

“Our research suggests that there may be a role for smell identification testing in clinically normal, older individuals who are at risk for Alzheimer’s disease,” said Growdon. “For example, it may prove useful to identify proper candidates for more expensive or invasive tests. Our findings are promising but must be interpreted with caution. These results reflect a snapshot in time; research conducted over time will give us a better idea of the utility of olfactory testing for early detection of Alzheimer’s.”

My Take: Exercise may reduce your risk of cognitive decline. For those who are able, aim for a minimum of 150 minutes per week of the equivalent of a brisk walk. I’m Dr. Michael Hunter.

Reference: Alzheimer’s Association. “Smell and eye tests show potential to detect Alzheimer’s early.” ScienceDaily. ScienceDaily, 13 July 2014. <www.sciencedaily.com/releases/2014/07/140713155512.htm>.

Not So Fast: Water Pipe Smoking May Increase Cancer Risk

hookah smoking water pipe

What You Need to Know: Young adults who smoked water pipes in hookah bars had elevated levels of nicotine, cotinine, tobacco-related cancer-causing agents, and volatile organic compounds (VOC) in their urine, and this may increase their risk for cancer and other chronic diseases, according to a study published in Cancer Epidemiology, Biomarkers & Prevention, a journal of the American Association for Cancer Research.

“This study reports systemic intake of tobacco-specific nitrosamines and VOCs after a typical water pipe-smoking session in a hookah bar setting, thus making the findings generalizable to most water pipe users in the United States,” said Gideon St.Helen, Ph.D., postdoctoral fellow in the Division of Clinical Pharmacology and the Center for Tobacco Control Research and Education at the University of California, San Francisco.

After a single evening of water pipe smoking in a hookah bar, young men and women had in their urine a 73-fold increase in nicotine; fourfold increase in cotinine; twofold increase in NNAL, a breakdown product of a tobacco-specific nitrosamine, NNK, which can cause lung and pancreatic cancers; and 14 to 91 percent increase in the breakdown products of VOC such as benzene and acrolein that are known to cause cancer and cardiovascular and respiratory diseases.

“There was also a substantial increase in nicotine levels, which raises concerns about the potential addictiveness of water pipe smoking and possible effects on the developing brains of children and youths who use water pipes,” added St.Helen. “Water pipe smoking is generally perceived to be a safe alternative to cigarette smoking, even for children and youths. Our study shows that water pipe use, particularly chronic use, is not risk-free.”

St. Helen and colleagues recruited 55 healthy, experienced water pipe smokers, ages 18 to 48 years, to the study. Participants were instructed to refrain from any type of smoking for a week. At the end of this period they provided a “before” urine sample and smoked water pipes at a hookah bar of their choice in the San Francisco Bay area. Soon after the visit, they provided the “after” urine sample, and filled a form to provide detailed information on their smoking session including total time spent smoking, number of bowls smoked, and number of shared users. They also provided a first-voided urine sample the next morning, which helped researchers estimate the clearance of the tobacco-related chemicals of interest. The study participants spent on average 74 minutes smoking water pipes and smoked an average 0.6 bowls of water pipe tobacco per person. Results: The researchers found that the elevated levels of nicotine, cotinine, and NNAL, which were detected immediately after the water pipe-smoking session, remained significantly elevated in the next-day urine samples, compared with the “before” samples: Nicotine was 10.4-fold higher; cotinine, 3.2-fold; and NNAL, 2.2-fold. Water pipe-smoking duration correlated significantly with the increase in post-exposure urine nicotine levels, and number of bowls smoked per person significantly correlated with the increase in post-exposure and next-day urine cotinine levels, respectively. The average increase in nicotine levels was comparable to levels obtained after smoking at least one cigarette, explained St.Helen.

“I have seen entire families, including young children, smoking water pipes. I have even been offered a smoke by my friend who thought water pipe smoking was ‘totally safe,'” St.Helen added. “Our study provides evidence that water pipe smoking leads to significant intake of tobacco-related addictive and harmful substances, and is therefore not without risk, particularly among children and youths.”

I’m Dr. Michael Hunter. The small print: The material presented herein is informational only, and is not designed to provide specific guidance for an individual. Please check with a valued health care provider with any questions or concerns. As for me, I am a Harvard- , Yale- and UPenn-educated radiation oncologist, and I practice in the Seattle, WA (USA) area. I feel genuinely privileged to be able to share with you. If you enjoyed today’s offering, please consider clicking the follow button at the bottom of this page. Available now: Understand Colon Cancer in 60 Minutes; Understand Brain Glioma in 60 Minutes. Both can be found at the Apple Ibooks store. Coming Soon for iPad: Understand Breast Cancer in 60 Minutes; Understand Colon Cancer in 60 Minute; Understand Colon Cancer in 60 Minutes; Understand Brain Glioma in 60 Minutes. Thank you. Reference: American Association for Cancer Research (AACR). “Water pipe smoking causes significant exposure to nicotine, cancer-causing agents.” ScienceDaily. ScienceDaily, 16 May 2014. <www.sciencedaily.com/releases/2014/05/140516091920.htm>.