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>.

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>.

Sitting Too Long? You May Increase Your Risk of Cancer

African American young woman

What You Need to Know: If you’re spending a lot of time sitting every day, either in front of the TV or at work, you may be at higher risk for developing certain types of cancer, according to new research published this week in the Journal of the National Cancer Institute.

The Evidence: The study found an additional two hours a day of sedentary behavior was linked to an 8% increase in colon cancer risk, a 10% increase in endometrial cancer risk and a 6% increase in risk for lung cancer. It did not find the same connection for breast, rectum, ovary and prostate cancers or for non-Hodgkin lymphoma.

  • Researchers came to these conclusions by analyzing 43 existing studies – that included more than 4 million study participants and 68,936 cancer cases – to measure the relationship between hours spent sitting and certain types of cancers.
  • It’s important to note that while the study identifies a link between sedentary behavior and an increased risk for certain cancers, the research doesn’t prove cause and effect.

“Does sitting in front of the TV cause colon cancer? No,” said Dr. Martin Heslin, chief of surgical oncology at the University of Alabama at Birmingham. “But the recommendations (of the study) are awesome.” Heslin, who was not involved in the research, says that in addition to sedentary behavior, several factors can increase your risk of cancer, including drinking or smoking too much, being obese and having a genetic predisposition.

 

It’s nearly impossible to say that any one of these factors causes someone to get a specific cancer, he says, but these are the behaviors we can control to help reduce our risk.

“You can affect TV time by turning it off,” said Heslin, though he acknowledges it’s not so easy to turn off work if you’re stuck in an office all day.

In that case, Heslin suggests looking for opportunities to leave your desk, such as standing up while working or taking a walk, to reduce the number of hours you spend sitting down.

“If I ever have the opportunity to design (a meeting room), I’m putting a waist-high table in the room, and no chairs,” Heslin said.

According to an editorial accompanying the study, organizations such as the American Cancer Society and the UK Department of Public Health address the need to reduce hours spent sitting, but do not offer any quantitative recommendations or strategies to help people improve. Daniela Schmid, one of the study’s co-authors and a faculty member in the University of Regensburg’s department of epidemiology and preventive medicine, hopes to change that.

“The findings of our study may encourage public health efforts to expand physical activity recommendations to reduce time spent in sedentary behavior,” Schmid said.

Previous studies support the findings in Schmid’s study. A 2012 study conducted by the National Institutes of Health concluded that sitting for several hours a day is bad for you, even if you are physically active. Researchers found even exercising at least 150 minutes each week – the generally accepted public health guideline for physical activity – can’t reverse the negative effects of sitting down for hours. In that study, sitting increased an individual’s risk for major chronic diseases such as Type 2 diabetes, cardiovascular disease, and breast and colon cancers.

My Take: If you sit regularly, get up periodically (even if that means every 20-30 minutes for a few minutes). In addition, aim for a minimum of 150 minutes per week of the equivalent of a brisk walk (for example, 30 minutes daily for five times per week). 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: CNN Health, 16 June 2014

The Future of Cancer Care: Therapy Based on Genomics Improves Survival

DNA Strands

Treatment for lung cancer has traditionally been based on the tumor’s histology (what it looks like under the microscope), but a new approach of basing treatment on genomic features has now been shown to result in better survival.

Results from the Lung Cancer Mutation Consortium (LCMC) show that patients who received genotype-directed therapy lived more than a year longer than those who did not.

The evidence that using targeted agents improves survival in lung cancer has been very difficult to show in clinical trials, but the current study shows that such an approach is not only feasible but successful. In fact, the study heralds a new era in the management of patients with a variety of cancers, Dr. Boris Pasche (Wake Forest University, USA) explains.

The Study: The LCMC, a collaborative, 14-center study led by Mark G. Kris, MD, from Memorial Sloan-Kettering Cancer Center, in New York City, tested tumors from 1007 patients with metastatic (spread to distant sites; incurable) lung adenocarcinomas for the presence 10 oncogenic driver mutations and then used the results to select agents that would target the drivers. The study was conducted from 2009 through 2012, and the patients’ tumors were tested for at least 1 gene, with full genotyping (testing for 10 genes) performed in 733 patients. For the other patients, the primary reason for the inability to test for all 10 genes was insufficient tissue.

The Small Print: An cancer driver was found in 466 (64%) of the patients who underwent full genotyping. So-called KRAS mutations were the most frequent, found in 182 (25%), followed by sensitizing EGFR in 122 (17%) and ALK rearrangements in 57 (8%). Less common drivers were other EGFR in 29 (4%), 2 or more genes in 24 (3%); ERBB2 (formerly HER2) in 19 (3%); BRAF in 16 (2%), PIK3CA in 6 (<1%), MET amplification in 5 (<1%), NRAS in 5 (<1%), and MEK1 in 1 (<1%). These results were then used to guide the choice of targeted therapy.

The Evidence: Overall, among 938 patients with adequate data, the median survival was 2.7 years. For patients with an oncogenic driver treated with targeted therapy, the median survival was 3.5 years, for patients with an oncogenic driver who were not treated with targeted therapy, the median survival was 2.4 years, and for patients with no driver identified, the median survival was 2.1 years (P < .001).

Among the different drivers that were identified, the longest survival was seen in patients with ALK-positive tumors (4.3 years).

“We are at the point now where we may be able to offer patients other treatments by studying the genomic features of their cancer. Until recently, we could not afford to do it because it cost about a million dollars for one genome. Now it’s as low as $900 to do the genome of a tumor, and it’s likely that will become even cheaper. And with better software, we would also be able to assess the unique features of that tumor vs other tumors and vs the normal DNA of that patient, and this is really the major change,” he said.

I’m Dr. Michael Hunter, and welcome to the future.

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: JAMA. 2014;311:1988-206; Medscape 20 May 2014

Is Lung Cancer Screening For You?

cigarette tobacco smoking lung cancer

The US Preventative Service Task Force recommends annual screening for lung cancer with low-dose CT scans for adults ages 55 to 80 who are at high risk for lung cancer because they have smoked a pack or more per day of cigarettes for at least 30 years and currently smoke or have quit within the past 15 years.

The Task Force issued its long-awaited guideline on lung cancer screening this week. It is estimated that this test could eventually prevent between 8,000 and 22,000 lung cancer deaths per year. About 95% of lung cancers are due to cigarette smoking. In the USA, 37% of Americans are current or former smokers, and 20% still smoke.

What is the US Preventative Service Task Force? The task force is an independent group of experts that makes evidence-based recommendations on preventative services such as screening, preventative medications and counseling services. Their process for developing guidelines involves an extensive review of scientific studies. The task force advises the US Department of Health and Human Services. The Affordable Care Act mandates that health insurance cover screenings that the task force deems useful.

Why Now? The latest recommendation is largely based on the National Cancer Institute’s National Lung Screening Trial. This study began in 2001, and is one of the best-designed cancer screening studies ever conducted. The study issued results fairly recently. Other organizations have issued similar recommendations, including the American College of Chest Surgeons, the American Society of Clinical Oncology, the American Thoracic Society, the American Association for Thoracic Surgery, the National Comprehensive Cancer Network, and the American Cancer Society.

What are the results of the NCI National Lung Screening Trial? The study assessed over 54,000 smokers and showed screening caused a 2-% decline in lung cancer deaths eight to ten years later. This means that 80% of lung cancer deaths still occurred.

Are there potential harms from screening? Yes. More than one in four people screened will have a finding that leads to further testing. Ultimately, 24 out of 25 who get further testing will not have lung cancer. Additional testing may include more imaging, as well as invasive tests such as biopsies or even surgery. In fact, in the National Lung Cancer Screening Trial, about one person died after an invasive procedure triggered by screening for every five to six lives saved because of screening.

My take: Low-dose screening studies reduce the risk of death from lung cancer, albeit with the potential costs detailed above. We also need a screening test for non-smokers and light smokers, as about 1 in 6 who get lung cancer are non-smokers. There is not great benefit to low-dose spiral CT screening for this population. Finally, don’t use screening as an excuse to continue smoking, as there is a greater benefit to quitting in general. 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: http://www.cnn.com/2014/01/03/health/brawley-lung-cancer/index.html?hpt=hp_bn13

I Smoke Cigarettes: Should I Consider a CT scan?

Beschreibung: Kleiner Lungentumor (T1) linker ...
Photo credit: Wikipedia

The benefits of screening high-risk populations for lung cancer with low-dose CT outweigh the harms if screening is implemented in a controlled manner, according to researchers in Canada.

Heidi C. Roberts, MD, of the department of medical imaging at the University of Toronto, and colleagues examined evidence from a recently completed systematic review by the American Cancer Society, the American College of Chest Physicians, ASCO and the National Comprehensive Cancer Network.

The key recommendations include:

  • Screening for lung cancer with low-dose CT is recommended in high-risk populations, defined as adults aged 55 to 74 years with a minimum smoking history of 30 pack-years or more.
  • Screening for lung cancer should be performed using a low-dose CT multidetector scanner with the following parameters: 120 kVp to 140 kVp, 20 mAs to 60 mAs, with an average effective dose of 1.5 mSv or less.
  • A nodule size of ≥5 mm found on the low-dose CT indicates a positive result and warrants a 3-month follow-up CT. Nodules of ≥15 mm should undergo immediate further diagnostic procedures to rule out definitive malignancy.
  • Follow-up CT of a nodule should be performed at 3 months as a limited low-dose CT scan
  • Patients at high risk for lung cancer should commence screening with an initial low-dose CT scan followed by annual screens for 2 consecutive years, followed by once every 2 years after each negative scan.

Here’s the perspective of Peter Mazzone, MD, MPH, FCCP (Director, Lung Cancer Program Respiratory Institute, Cleveland Clinic):

The latest lung cancer screening guideline from the Cancer Care Ontario’s Program in Evidence-Based Care used a prior systematic review as the evidence base to develop recommendations. Several key recommendations were similar to other published guidelines, inlcuding the definition of the high-risk group to screen (aged 55-74 years, 30 pack-years minimum, smoked within the past 15 years) as well as the need to screen within a formal program capable of providing high quality imaging, interpretation and management of imaging findings. Other recommendations provided practical advice where evidence is not available to confirm or refute the approach. For example, 5 mm was suggested as the size of a solid nodule that should be used as the threshold for a positive study; a three-month CT follow-up of positive studies; and annual screening for 3 years to be followed by screening every second year. The latter recommendations can be debated until additional evidence is available.

I’m Dr. Michael Hunter. If you smoke, please consider quitting. If you have already quit, congratulations. Don’t go back. And if you have a significant history of cigarette use, consider getting  CT scans to screen for lung cancer. Thanks!

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: Roberts H. J Thorac Oncol. 2013; doi:10.1097/JTO.0b013e31829fd3d5.