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!

Acupuncture: Can It Help With Radiation-Linked Dry Mouth?

What You Need to Know: Acupuncture can relieve the symptoms of dry mouth in patients undergoing radiotherapy, according to the largest trial yet to investigate this effect. Radiotherapy for head and neck cancer often produces this unpleasant and distressing side effect because patients’ salivary glands are damaged by the radiation.

Background: Approximately half a million people develop head and neck cancer each year, and few effective treatments currently exist for dry mouth, or xerostomia, which is a common side effect of radiotherapy. Five years after radiotherapy, as many as 41% of patients may still have dry mouth. Xerostomia affects patients’ quality of life because it interferes with taste, chewing, speaking, and sleeping.

The Study: Seven cancer centers in the United Kingdom recruited a cumulative 145 patients with radiation-induced xerostomia. The patients were randomized to receive group acupuncture sessions for 20 minutes every week for 8 weeks, or to receive two oral care educational sessions for 1 hour, 1 month apart. Four weeks after the end of these two types of care, the patients were switched to the other treatment.

Symptoms of xerostomia were measured objectively with Schirmer strips, which are paper strips that measure the amount of saliva in the mouth. A quality of life (QOL) questionnaire measured the patients’ subjective reporting of how their mouths felt through questions about individual symptoms such as sticky saliva, dry lips, needing to sip water to relieve a dry mouth, needing to sip water to swallow food, and waking at night to sip water.

Results: Although there were no significant changes in saliva production, patients who had received 8 weeks of acupuncture were twice as likely to report improved dry mouth as patients who were receiving oral care. Individual symptoms also significantly improved for the group receiving acupuncture.

The researchers stated that the subjective reporting of improvements in xerostomia was of more significance than the lack of changes in the objective test with the Schirmer strips. Richard Simcock, MRCP, FRCR, clinical oncologist at the Sussex Cancer Centre and an author of the study, explained, “There was no clear relationship between a patient indicating they had a very dry mouth and the measurement of saliva on the Schirmer strips. By definition these patients with chronic xerostomia produced little or no saliva, making objective measurements really difficult.”

The researchers did not feel the improvements in xerostomia were due to a placebo effect. Dr. Valerie Jenkins, of University of Sussex, who supervised the research, explained, “The profound impact that xerostomia exerts on functions such as eating, talking and sleeping, which were relieved by the acupuncture means that if it is entirely a placebo effect than this is a pretty powerful placebo. In addition, the results showed that patients were less likely to wake at night to sip water after treatment – this effect seems difficult to ascribe solely to placebo.”

Dr. Simcock stated, “This is a very neglected group of patients suffering from a most unpleasant side-effect of treatment for which all other ameliorative interventions have failed to address adequately. The acupuncture intervention has been designed in a way that allows it to be delivered simply and cheaply in normal hospital surroundings and yet still produces a significant benefit for patients with a chronic symptom.”

This study was reported in the Annals of Oncology (2012; doi:10.1093/annonc/mds515). Reported online October 29, 2012 in OncologyNurseAdvisor.  I’m Dr. Michael Hunter.

Head & Neck Cancer: Sophisticated Radiation herapy Improves Survival

radiation therapy linear accelerator

What You Need to Know: Patients with head and neck cancers treated with intensity-modulated radiation therapy (IMRT) experience significant improvements in cause-specific survival (CSS) compared with patients treated with non-IMRT techniques, according to a study published online Jan. 13 in Cancer.

The Evidence: Beth M. Beadle, MD, PhD, from the University of Texas MD Anderson Cancer Center in Houston, and colleagues compared the cause-specific survival for 3,172 patients with head and neck cancers treated with IMRT versus non-IMRT from 1999 to 2007. Information on CSS was extracted from the US Surveillance, Epidemiology, and End Results-Medicare database.

Results:

  • Over a median follow-up of 40 months, patients treated with IMRT had a statistically significant improvement in CSS compared with those treated with non-IMRT (84.1% versus 66.0%; P < 0.001). 
  • All subgroups of patients treated with IMRT had better CSS than those treated with non-IMRT, when each body subsite in the head and neck region was analyzed separately.
  • Patients treated with IMRT were associated with better CSS (hazard ratios, 0.72 for propensity score matching and 0.60 for instrumental variable analysis), in multivariable survival analyses.

“This suggests there may be benefits to IMRT in cancer outcomes, in addition to toxicity reduction, for this patient population,” the researchers wrote.

My Take: IMRT can not only reduce the side effects associated with radaition therapy, but appears to improve survival among those with cancer of the head and neck region. I’m Dr. Michael Hunter.

Reference: Beadle BM, Liao KP, Elting LS, et al. Improved survival using intensity-modulated radiation therapy in head and neck cancers: A SEER-Medicare analysis. Cancer. 2014;diu:10.1002/cncr.28372.

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.

For Oral Health, Have a Tea Party

green tea cup and plants

Epidemiological studies evaluating the association of tea consumption and the risk of oral cancer risk have produced inconsistent results. Thus, the authors of a recent study conducted a meta-analysis (study of studies) to assess the relationship between tea consumption and oral cancer risk.

METHODS: Pertinent studies were identified by a search in PubMed, Web of Knowledge and Wan Fang Med Online. The fixed or random effect model was used based on heterogeneity test. Publication bias was estimated using Egger’s regression asymmetry test.

RESULTS: 14 articles with 19 studies comprising 4675 oral cancer cases were included in this meta-analysis. The relative risk (95% confidence interval) of oral cancer for the highest versus the lowest category of tea consumption was 0.853 (0.779-0.934), and the association was significant between oral cancer risk and green tea consumption [0.798 (0.673-0.947)] but not in the black tea consumption [0.953 (0.792-1.146)]. [This implies that you can reduce the risk by about 1/5th if you consume green tea.]

TAKE-AWAY MESSAGE: Tea consumption may have a protective effect on oral cancer, especially green tea consumption. Previous studies suggested that coffee may lower the risk of cancer of the mouth region, but now we know green tea may work, too! Obviously, more research is needed, but the link seems logical. 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: Oral Oncol. 2014 Jan 2. pii: S1368-8375(13)00802-6. doi: 10.1016/j.oraloncology.2013.12.014. [Epub ahead of print]

HPV: How Does It Damage Genes?

HPV Cell Entry
HPV Cell Entry (Photo credit: AJC1)

The virus that causes cervical, head and neck, anal and other cancers can damage chromosomes and genes where it inserts its DNA into human DNA, according to a new study led by researchers at The Ohio State University Comprehensive Cancer Center — Arthur G. James Cancer Hospital and Richard J. Solove Research Institute.

Background: HPV causes about 610,000 cancers annually worldwide, including virtually all cervical cancers, and many anogenital and head and neck cancers. How it causes cancer isn’t completely understood. It’s long been known that cancer-causing types of human papillomavirus (HPV) produce two viral proteins, called E6 and E7, which are essential for the development of cancer. However, they are not sufficient to cause cancer. Additional alterations in host-cell genes are necessary for cancer to develop. Here, scientists identified a new mechanism by which HPV may damage host DNA directly and contribute to cancer development.

The Study: Published in the journal Genome Research, this laboratory study used whole-genome sequencing to investigate the relationship between the HPV and host genomes in human cancers.

“Our sequencing data showed in vivid detail that HPV can damage host-cell genes and chromosomes at sites of viral insertion,” says co-senior author David Symer. HPV can act like a tornado hitting the genome, disrupting and rearranging nearby host-cell genes. This can lead to overexpression of cancer-causing genes in some cases, or it can disrupt protective tumor-suppressor genes in others. Both kinds of damage likely promote the development of cancer.”

“We observed fragments of the host-cell genome to be removed, rearranged or increased in number at sites of HPV insertion into the genome,” says co-senior author Maura Gillison, MD, PhD, professor of medicine, epidemiology and otolaryngology and the Jeg Coughlin Chair of Cancer Research at the OSUCCC — James. “These remarkable changes in host genes were accompanied by increases in the number of HPV copies in the host cell, thereby also increasing the expression of viral E6 and E7, the cancer-promoting genes.” The two cancer-causing proteins, E6 and E7, silence two key tumor-suppressor genes in host cells, contributing to cancer development. “E6 and E7 are critically important for the virus to cause cancer. Our findings shed light on how HPV, and perhaps other viruses, can disrupt the structure of host chromosomes and genes and thereby contribute to cancer development,” Gillison explains.

For this study, Symer, Gillison and their colleagues examined 10 cancer-cell lines and two head and neck tumor samples from patients. Along with whole-genome sequencing, the scientists used several molecular assays, including RNA sequencing, spectral karyotyping (SKY) and fluorescence in situ hybridization (FISH).

“Our study reveals new and interesting information about what happens to HPV in the ‘end game’ in cancers,” Symer says. “Overall, our results shed new light on the potentially critical, catastrophic steps in the progression from initial viral infection to development of an HPV-associated cancer.”

I’m Dr. Michael Hunter.

Reference: K. Akagi, J. Li, T. R. Broutian, H. Padilla-Nash, W. Xiao, B. Jiang, J. W. Rocco, T. N. Teknos, B. Kumar, D. Wangsa, D. He, T. Ried, D. E. Symer, M. L. Gillison. Genome-wide analysis of HPV integration in human cancers reveals recurrent, focal genomic instability. Genome Research, 2013; DOI: 10.1101/gr.164806.113

HPV-related Head & Neck Cancer: Personalizing Management

Can We De-escalate Nonsurgical Treatment? Combination chemotherapy and radiation therapy is the gold standard for management of oropharynx cancer. While HPV-related oropharyngeal carcinoma has a relatively high cure rate (over 80%) for stage III-IV at many institutions, side effects can be severe. Researchers are trying to answer the question of whether we can give less treatment, while not compromising cure chances. In the ongoing Quarterback Trial in the USA, patients with Stage III-IV HPV-related oropharynx cancer are randomized to reduced dose radiation therapy, carboplatin chemotherapy, and Erbitux targeted therapy versus standard-dose radiation therapy plus carboplatin.

hpv vaccine
HPV vaccine (Photo credit: VCU CNS)

My take: It’ll probably work. For those with children, consider vaccines against HPV. Boys and girls ages 11 or 12 through 26 (for girls) and 21 (for boys) should ask their health care provider about the vaccine. Others for which it is recommended include gay and bisexual men (or any man who has sex with a man), men and women with compromised immune systems (including those with HIV/AIDS) through age 26, if they did not get fully vaccinated when they were younger.

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.

References:

Centers for Disease Control and Prevention (http://www.cdc.gov/hpv/vaccine.html)