VOLUME
32
䡠
NUMBER
22
䡠
AUGUST
1
2014
JOURNAL OF CLINICAL ONCOLOGY
E
D
I
T
O
R
I
A
L
Milking the Evidence: Diet Does Matter Donald I. Abrams, San Francisco General Hospital; University of California San Francisco Osher Center for Integrative Medicine; University of California San Francisco, San Francisco, CA See accompanying article on page 2335
Dietary risks now rank number one among 17 leading risk factors contributing to the number of deaths and percentage of disabilityadjusted–life-years for both sexes combined in the United States.1 The aggregate of the 14 subcomponents of diet (ie, diet low in fruits, vegetables, whole grains, nuts and seeds, milk, fiber, calcium, seafood omega-3 fatty acids, polyunsaturated fatty acids; diet high in red meat, processed meats, sugar-sweetened beverages, trans-fatty acids, sodium2) assessed by the US Burden of Disease Collaborators surpasses the impact of tobacco smoking on the nation’s morbidity and mortality and does not include high body mass index and physical inactivity (ranking fourth and fifth in contributing to overall deaths). It has been estimated that as many avoidable malignancies are related to diet as tobacco (30% to 35%), again not accounting for the significant additional contribution of obesity (14% to 20%).3 As oncologists become more aware of these undeniable associations, it becomes a critical part of our job to be able to answer patients’ questions about nutrition during and after cancer treatment and not default to the unhelpful “it doesn’t really matter, eat what you want” which may not be in the best interest of the patient. As specialists dealing with cytotoxic therapies, oncologists demand a strong evidence base before recommending a course of treatment to patients. Often we have followed the progression of a new therapeutic agent from phase I and II through to the large randomized phase III clinical trials. We carefully assess disease-free survival, overall survival, and adverse effects before feeling comfortable delineating the risks and benefits for the patient deciding on treatment options. It is not surprising that we might demand a similar level of evidence in discussing lifestyle modification and particularly nutrition interventions with our patients. Yet we find that the degree of certainty that we are accustomed to in phase III trials is lacking. After all, it is difficult to randomly assign people to consume soyfoods or not for the next 20 years, and even more of a challenge to find an appropriate placebo for tofu should we really want to conduct a convincing investigation. In vitro studies of isolated food components in cell culture or in animal studies abound in the literature but may be difficult to extrapolate to the human situation. Hence, we are often dependent on data from epidemiologic analyses to provide us with guidance. Epidemiologic data, however, are often conflicting and add to our confusion. Meyerhardt et al4 convincingly described the increased risk of recurrence and mortality in stage III colon cancer patients participating in a Cancer and Leukemia Group B (CALGB) adjuvant chemotherapy trial consuming a “Western” diet— characterized by high intake of meat, fat, refined grains 2290
© 2014 by American Society of Clinical Oncology
and dessert— compared with those with a more “prudent” menu consisting of increased fruits, vegetables, poultry and fish. However, in a prior analysis of the prospective cohort in the Cancer Prevention Study II (CPS-II) Nutrition Cohort, investigators reported that although prediagnosis consumption of red meat was associated with a decreased risk of colon cancer, postdiagnosis red meat consumption had no impact on survival outcomes.5 This seems to contradict the previously reported highly significant benefit of consuming a diet with limited red meat after diagnosis. Or perhaps the benefit of the “prudent diet” was something other than decreased red meat. Taking a more holistic view, maybe it was the contribution of the overall dietary pattern and not a single nutrient. In the article that accompanies this editorial, American Cancer Society investigators report additional findings from the prospective CPS-II Nutrition Cohort.6 In this analysis, although higher intake of calcium, vitamin D and dairy products were all associated with lower incidence of colorectal cancer, postdiagnosis it was only the calcium and milk intake that were linked to better outcomes. Of note, patients in the highest quartile of total calcium intake in this analysis were more likely to have a normal body mass index, be more physically active, consume fewer calories and eat more fruits and vegetables, folate-rich foods, whole grains and less red and processed meat (all P values ⬍ .01). In other words, the investigators found that the patients with best outcomes were those who conformed to the American Institute for Cancer Research/World Cancer Research Fund recommendation that “after treatment, cancer survivors should follow the recommendations for cancer prevention.”7; The American Institute for Cancer Research/ World Cancer Research Fund guidelines parallel the American Cancer Society’s own8 and advise that individuals aim to be as lean as possible without being underweight; be physically active for 30 minutes each day; consume more fruits, vegetables and whole grains; avoid sugary drinks and other energy dense foods; and limit consumption of red meats and avoid processed meats.7 Explicitly stating that survivors follow the same guidelines as those seeking cancer risk reduction makes intuitive sense, but our efforts to obtain the data to satisfy our need for evidence on which to base our recommendations constantly disappoint. For example, the Women’s Healthy Eating and Living study (WHEL) received much media attention when it reported that fruit and vegetable intake showed no benefit in women with breast cancer.9 In this large trial of woman following treatment for stage I-III breast cancer, the experimental arm was randomly assigned to a high fruit Journal of Clinical Oncology, Vol 32, No 22 (August 1), 2014: pp 2290-2292
Downloaded from jco.ascopubs.org on October 21, 2014. For personal use only. No other uses without permission. Copyright © 2014 American Society of Clinical Oncology. All rights reserved.
Editorial
and vegetable diet while the control group was just given the Five-ADay information booklet on healthy consumption of fruit and vegetables. Although women in the experimental arm consistently consumed significantly more fruits and vegetables over the course of the trial, women in the control group reported 7.9 servings of fruits and vegetables daily which far exceeded the US norms. Hence, just by participating in the study, the control group altered their behavior significantly, thereby compromising our ability to detect a potential benefit in the experimental arm. Before recommending that all patients with colorectal cancer drink more milk, some caveats are worth mentioning. Despite all of the potential health benefits Yang et al6 enumerate, dairy is a significant source of saturated fat. However, it is not the fat that is the most problematic. Although we talk about lactose intolerance as if it is a disorder or a disease, in fact it is the norm. In most human populations, as in nonhuman mammals, lactase activity decreases by midchildhood (age 5 years in humans) such that lactase nonpersistence is the rule, not the exception.10 Lactase persistence is generally limited to a minority of our population, particularly northern Europeans. The fact that 98% of the participants in this cohort were white—a shortcoming itself- would also bias the findings in favor of people able to digest lactose. In addition, dairy protein consumption has been positively associated with elevated levels of insulin-like growth factor-I which has been implicated with increased risk of colorectal carcinomas.11 Not to mention the ongoing concern that dairy consumption and calcium may lead to an increased risk of other malignancies, particularly prostate cancer. Alas, three recent metaanalyses all reached different conclusions on the dairy-prostate cancer connection.12-14 Yang et al6 exclude patients with distant metastatic disease from their analysis stating that the 5-year survival in this group is so poor that diet would not likely impact mortality. In view of the fact that oligometastatic colorectal cancer is becoming potentially curable in an increasing number of patients,15 it seems unfortunate that these analyses have not been done in this, and the previously published red meat, report. Cancer patients are frequently highly motivated to make lifestyle changes that might impact on their prognosis. If dietary manipulation were to have any benefit in patients with metastatic disease, that would be worthwhile information for us to share. With all of this conflicting and confusing information and the tremendous amount of treatment advances the conventional oncologist needs to keep up with, it is little wonder that the default is to tell patients “it doesn’t really matter what you eat” or “there is no good evidence to support” dietary interventions. A New England Journal of Medicine commentary on treating hypercholesterolemia published in 1989 that impacted significantly on my subsequent practice of medicine makes an observation that is germane to the discussion of nutrition recommendations for evidence-driven oncologists: “Physicians should recognize the qualitative differences between advising changes in diet and prescribing drug therapy. In the case of diet and other types of behavior, a patient can determine on a daily basis what is appropriate. As long as a recommended type of behavior is at worst harmless, it may be ethically proposed without unequivocal proof of benefit; the possibility of benefit may suffice. On the other hand, pharmacologic interventions are powerful symbols of the triumph of medical technology. Patients are likely to believe implicitly that the benefits of drugs clearly outweigh the risks. The physician who proposes drug therapy www.jco.org
is therefore obligated to offer relatively stronger evidence of a favorable ratio of benefit to harm.”16 The cover story of the December 19, 2012, issue of the ASCO Connection featured “Improving Outcomes: Discussing Healthy Lifestyle Choices with Your Patients.”17 With the time constraints of a follow-up visit and the uncertainty regarding the most current data on the topic, it is totally understandable that the treating oncologist may be reluctant to engage in a conversation about nutrition. Patients may question the benefits of fad diets that are touted to be cancer cures.18 Or they may just want advice on what to eat and what to avoid to improve their outcome. Not receiving such information from their oncologist may be disappointing. The options are to refer to an oncology nutritionist or perhaps seek assistance from an integrative oncologist. Integrative medicine provides relationship-centered care with an emphasis on addressing the needs of the whole person.19,20 The integrative oncologist may equate cancer to a weed and the patient to a garden, sharing information on how to make the soil as inhospitable as possible to growth and spread of the weed. Having heard advice on how to best fertilize the soil, our patients regain a sense of control, learning something they themselves can do to contribute to their health and well-being, empowering them in their continued journey with and beyond cancer. AUTHOR’S DISCLOSURES OF POTENTIAL CONFLICTS OF INTEREST
The author(s) indicated no potential conflicts of interest. REFERENCES 1. US Burden of Disease Collaborators: The State of US Health, 1990-2010: Burden of diseases, injuries and risk factors, JAMA 310: 591-608, 2013 2. Lim SS, Vos T, Flaxman AD, et al: A comparative assessment of burden of disease and injury attributable to 67 risk factors and risk factor clusters in 21 regions, 1990-2010: A systematic analysis for the Global Burden of Disease Study 2010. Lancet 380:2224-2260, 2012 3. Coussens LM, Zitvogel L, Palucka AK: Neutralizing tumor-promoting chronic inflammation: A magic bullet? Science 339:286-291, 2013 4. Meyerhardt JA, Niedzwiecki D, Hollis D, et al: Association of dietary patterns with cancer recurrence and survival in patients with stage III colon cancer. JAMA 298:754-764, 2007 5. McCullough ML, Gapstur SM, Shah R, et al: Association between red and processed meat intake and mortality among colorectal cancer survivors. J Clin Oncol 31:2773-2782, 2013 6. Yang B, McCullough ML, Gapstur SM, et al: Calcium, vitamin D, dairy products, and mortality among colorectal cancer survivors: The Cancer Prevention Study-II Nutrition Cohort. J Clin Oncol 32:2335-2343, 2014 7. American Institute for Cancer Research/World Cancer Research Fund: Food, Nutrition, Physical Activity and the Prevention of Cancer: A Global Perspective. Washington, DC, American Institute for Cancer Research, 2007 8. Kushi LH, Doyle C, McCullough M, et al: American Cancer Society guidelines on nutrition and physical activity for cancer prevention. CA Cancer J Clin 62:30-67, 2012 9. Pierce JP, Natarajan L, Caan BJ, et al: Influence of a diet very high in vegetables, fruit, and fiber and low in fat on prognosis following treatment for breast cancer: The Women’s Healthy Eating and Living (WHEL) randomized trial. JAMA 298:289-298, 2007 10. Montgomery RK, Krasinski SD, Hirshhorn JN, et al: Lactose and lactase: Who is lactose intolerant and why? J Pediatr Gastroenterol Nutr 45:S131-S137, 2007 11. Crowe FL, Key TJ, Allen NE, et al: The association between diet and serum concentrations of IGF-I, IGFBP-I, IGFBP-2, and IGFBP-3 in the European Prospective Investigation into Cancer and Nutrition. Cancer Epidemiol Biomarkers Prev 18:1333-1340, 2009 12. Gao X, LaValley MP, Tucker KL: Prospective studies of dairy products and calcium intakes and prostate cancer risk: A meta-analysis. J Natl Cancer Inst 97:1768-1777, 2005 13. Qin LQ, Xu JY, Wang PY, et al: Milk consumption is a risk factor for prostate cancer in Western countries: Evidence from cohort studies. Asia Pac J Clin Nutr 16:467-476, 2007
© 2014 by American Society of Clinical Oncology
Downloaded from jco.ascopubs.org on October 21, 2014. For personal use only. No other uses without permission. Copyright © 2014 American Society of Clinical Oncology. All rights reserved.
2291
Editorial
14. Huncharek M, Muscat J, Kupelnick B: Dairy products, dietary calcium and vitamin D intake as risk factors for prostate cancer: A meta-analysis of 26,769 cases from 45 observational studies. Nutr Cancer 60:421-441, 2008 15. Van Loon K, Venook AP: Curable patient with metastatic colorectal cancer: Balancing effective therapies and toxicities. J Clin Oncol 32:991-996, 2014 16. Brett AS: Treating hypercholesterolemia: How should practicing physicians interpret the published data for patients? N Engl J Med 332:676-680, 1989 17. Anderson V: Improving outcomes: Discussing healthy lifestyle choices with your patients. ASCO Connection 19 Dec 2012. https://connection.asco.org/ Magazine/Article/id/3402/Improving-Outcomes-Discussing-Healthy-LifestyleChoices-with-Your-Patients.aspx
18. Huebner J, Marienfeld S, Abbenhardt C, et al: Counseling patients on cancer diets: A critical review of the literature and recommendations for clinical practice. Anticancer Res 34:39-48, 2014 19. Deng GE, Frenkel M, Cohen L, et al: Evidence-based clinical practice guidelines for integrative oncology: Complementary therapies and botanicals. J Soc Integr Oncol 7:85-120, 2009 20. Abrams DI: Integrative oncology: The role of nutrition. In Leser M, Ledesma N, Bergerson S, Trujillo E (eds): Oncology Nutrition for Clinical Practice. Cicago, IL, Oncology Nutrition Dietetic Practice Group of the Academy of Nutrition and Dietetics, 2013, pp 53-60
DOI: 10.1200/JCO.2014.56.6299; published online ahead of print at www.jco.org on June 23, 2014
■ ■ ■
Help Your Patients Learn About Managing the Cost of Cancer Care Do your patients have financial questions about cancer care? Cancer.Net’s Managing the Cost of Cancer Care booklet provides tools and resources that can help your patients answer these questions and plan for costs before, during, and after treatment. Order copies of the booklet for your patients through the ASCO University Bookstore at www.cancer.net/estore. ASCO members receive a 20% discount. The booklet is also available as a downloadable PDF in English and Spanish at cancer.net/managingcostofcare.
2292
© 2014 by American Society of Clinical Oncology
JOURNAL OF CLINICAL ONCOLOGY
Downloaded from jco.ascopubs.org on October 21, 2014. For personal use only. No other uses without permission. Copyright © 2014 American Society of Clinical Oncology. All rights reserved.
32
䡠
NUMBER
22
䡠
AUGUST
1
2014
JOURNAL OF CLINICAL ONCOLOGY
E
D
I
T
O
R
I
A
L
Milking the Evidence: Diet Does Matter Donald I. Abrams, San Francisco General Hospital; University of California San Francisco Osher Center for Integrative Medicine; University of California San Francisco, San Francisco, CA See accompanying article on page 2335
Dietary risks now rank number one among 17 leading risk factors contributing to the number of deaths and percentage of disabilityadjusted–life-years for both sexes combined in the United States.1 The aggregate of the 14 subcomponents of diet (ie, diet low in fruits, vegetables, whole grains, nuts and seeds, milk, fiber, calcium, seafood omega-3 fatty acids, polyunsaturated fatty acids; diet high in red meat, processed meats, sugar-sweetened beverages, trans-fatty acids, sodium2) assessed by the US Burden of Disease Collaborators surpasses the impact of tobacco smoking on the nation’s morbidity and mortality and does not include high body mass index and physical inactivity (ranking fourth and fifth in contributing to overall deaths). It has been estimated that as many avoidable malignancies are related to diet as tobacco (30% to 35%), again not accounting for the significant additional contribution of obesity (14% to 20%).3 As oncologists become more aware of these undeniable associations, it becomes a critical part of our job to be able to answer patients’ questions about nutrition during and after cancer treatment and not default to the unhelpful “it doesn’t really matter, eat what you want” which may not be in the best interest of the patient. As specialists dealing with cytotoxic therapies, oncologists demand a strong evidence base before recommending a course of treatment to patients. Often we have followed the progression of a new therapeutic agent from phase I and II through to the large randomized phase III clinical trials. We carefully assess disease-free survival, overall survival, and adverse effects before feeling comfortable delineating the risks and benefits for the patient deciding on treatment options. It is not surprising that we might demand a similar level of evidence in discussing lifestyle modification and particularly nutrition interventions with our patients. Yet we find that the degree of certainty that we are accustomed to in phase III trials is lacking. After all, it is difficult to randomly assign people to consume soyfoods or not for the next 20 years, and even more of a challenge to find an appropriate placebo for tofu should we really want to conduct a convincing investigation. In vitro studies of isolated food components in cell culture or in animal studies abound in the literature but may be difficult to extrapolate to the human situation. Hence, we are often dependent on data from epidemiologic analyses to provide us with guidance. Epidemiologic data, however, are often conflicting and add to our confusion. Meyerhardt et al4 convincingly described the increased risk of recurrence and mortality in stage III colon cancer patients participating in a Cancer and Leukemia Group B (CALGB) adjuvant chemotherapy trial consuming a “Western” diet— characterized by high intake of meat, fat, refined grains 2290
© 2014 by American Society of Clinical Oncology
and dessert— compared with those with a more “prudent” menu consisting of increased fruits, vegetables, poultry and fish. However, in a prior analysis of the prospective cohort in the Cancer Prevention Study II (CPS-II) Nutrition Cohort, investigators reported that although prediagnosis consumption of red meat was associated with a decreased risk of colon cancer, postdiagnosis red meat consumption had no impact on survival outcomes.5 This seems to contradict the previously reported highly significant benefit of consuming a diet with limited red meat after diagnosis. Or perhaps the benefit of the “prudent diet” was something other than decreased red meat. Taking a more holistic view, maybe it was the contribution of the overall dietary pattern and not a single nutrient. In the article that accompanies this editorial, American Cancer Society investigators report additional findings from the prospective CPS-II Nutrition Cohort.6 In this analysis, although higher intake of calcium, vitamin D and dairy products were all associated with lower incidence of colorectal cancer, postdiagnosis it was only the calcium and milk intake that were linked to better outcomes. Of note, patients in the highest quartile of total calcium intake in this analysis were more likely to have a normal body mass index, be more physically active, consume fewer calories and eat more fruits and vegetables, folate-rich foods, whole grains and less red and processed meat (all P values ⬍ .01). In other words, the investigators found that the patients with best outcomes were those who conformed to the American Institute for Cancer Research/World Cancer Research Fund recommendation that “after treatment, cancer survivors should follow the recommendations for cancer prevention.”7; The American Institute for Cancer Research/ World Cancer Research Fund guidelines parallel the American Cancer Society’s own8 and advise that individuals aim to be as lean as possible without being underweight; be physically active for 30 minutes each day; consume more fruits, vegetables and whole grains; avoid sugary drinks and other energy dense foods; and limit consumption of red meats and avoid processed meats.7 Explicitly stating that survivors follow the same guidelines as those seeking cancer risk reduction makes intuitive sense, but our efforts to obtain the data to satisfy our need for evidence on which to base our recommendations constantly disappoint. For example, the Women’s Healthy Eating and Living study (WHEL) received much media attention when it reported that fruit and vegetable intake showed no benefit in women with breast cancer.9 In this large trial of woman following treatment for stage I-III breast cancer, the experimental arm was randomly assigned to a high fruit Journal of Clinical Oncology, Vol 32, No 22 (August 1), 2014: pp 2290-2292
Downloaded from jco.ascopubs.org on October 21, 2014. For personal use only. No other uses without permission. Copyright © 2014 American Society of Clinical Oncology. All rights reserved.
Editorial
and vegetable diet while the control group was just given the Five-ADay information booklet on healthy consumption of fruit and vegetables. Although women in the experimental arm consistently consumed significantly more fruits and vegetables over the course of the trial, women in the control group reported 7.9 servings of fruits and vegetables daily which far exceeded the US norms. Hence, just by participating in the study, the control group altered their behavior significantly, thereby compromising our ability to detect a potential benefit in the experimental arm. Before recommending that all patients with colorectal cancer drink more milk, some caveats are worth mentioning. Despite all of the potential health benefits Yang et al6 enumerate, dairy is a significant source of saturated fat. However, it is not the fat that is the most problematic. Although we talk about lactose intolerance as if it is a disorder or a disease, in fact it is the norm. In most human populations, as in nonhuman mammals, lactase activity decreases by midchildhood (age 5 years in humans) such that lactase nonpersistence is the rule, not the exception.10 Lactase persistence is generally limited to a minority of our population, particularly northern Europeans. The fact that 98% of the participants in this cohort were white—a shortcoming itself- would also bias the findings in favor of people able to digest lactose. In addition, dairy protein consumption has been positively associated with elevated levels of insulin-like growth factor-I which has been implicated with increased risk of colorectal carcinomas.11 Not to mention the ongoing concern that dairy consumption and calcium may lead to an increased risk of other malignancies, particularly prostate cancer. Alas, three recent metaanalyses all reached different conclusions on the dairy-prostate cancer connection.12-14 Yang et al6 exclude patients with distant metastatic disease from their analysis stating that the 5-year survival in this group is so poor that diet would not likely impact mortality. In view of the fact that oligometastatic colorectal cancer is becoming potentially curable in an increasing number of patients,15 it seems unfortunate that these analyses have not been done in this, and the previously published red meat, report. Cancer patients are frequently highly motivated to make lifestyle changes that might impact on their prognosis. If dietary manipulation were to have any benefit in patients with metastatic disease, that would be worthwhile information for us to share. With all of this conflicting and confusing information and the tremendous amount of treatment advances the conventional oncologist needs to keep up with, it is little wonder that the default is to tell patients “it doesn’t really matter what you eat” or “there is no good evidence to support” dietary interventions. A New England Journal of Medicine commentary on treating hypercholesterolemia published in 1989 that impacted significantly on my subsequent practice of medicine makes an observation that is germane to the discussion of nutrition recommendations for evidence-driven oncologists: “Physicians should recognize the qualitative differences between advising changes in diet and prescribing drug therapy. In the case of diet and other types of behavior, a patient can determine on a daily basis what is appropriate. As long as a recommended type of behavior is at worst harmless, it may be ethically proposed without unequivocal proof of benefit; the possibility of benefit may suffice. On the other hand, pharmacologic interventions are powerful symbols of the triumph of medical technology. Patients are likely to believe implicitly that the benefits of drugs clearly outweigh the risks. The physician who proposes drug therapy www.jco.org
is therefore obligated to offer relatively stronger evidence of a favorable ratio of benefit to harm.”16 The cover story of the December 19, 2012, issue of the ASCO Connection featured “Improving Outcomes: Discussing Healthy Lifestyle Choices with Your Patients.”17 With the time constraints of a follow-up visit and the uncertainty regarding the most current data on the topic, it is totally understandable that the treating oncologist may be reluctant to engage in a conversation about nutrition. Patients may question the benefits of fad diets that are touted to be cancer cures.18 Or they may just want advice on what to eat and what to avoid to improve their outcome. Not receiving such information from their oncologist may be disappointing. The options are to refer to an oncology nutritionist or perhaps seek assistance from an integrative oncologist. Integrative medicine provides relationship-centered care with an emphasis on addressing the needs of the whole person.19,20 The integrative oncologist may equate cancer to a weed and the patient to a garden, sharing information on how to make the soil as inhospitable as possible to growth and spread of the weed. Having heard advice on how to best fertilize the soil, our patients regain a sense of control, learning something they themselves can do to contribute to their health and well-being, empowering them in their continued journey with and beyond cancer. AUTHOR’S DISCLOSURES OF POTENTIAL CONFLICTS OF INTEREST
The author(s) indicated no potential conflicts of interest. REFERENCES 1. US Burden of Disease Collaborators: The State of US Health, 1990-2010: Burden of diseases, injuries and risk factors, JAMA 310: 591-608, 2013 2. Lim SS, Vos T, Flaxman AD, et al: A comparative assessment of burden of disease and injury attributable to 67 risk factors and risk factor clusters in 21 regions, 1990-2010: A systematic analysis for the Global Burden of Disease Study 2010. Lancet 380:2224-2260, 2012 3. Coussens LM, Zitvogel L, Palucka AK: Neutralizing tumor-promoting chronic inflammation: A magic bullet? Science 339:286-291, 2013 4. Meyerhardt JA, Niedzwiecki D, Hollis D, et al: Association of dietary patterns with cancer recurrence and survival in patients with stage III colon cancer. JAMA 298:754-764, 2007 5. McCullough ML, Gapstur SM, Shah R, et al: Association between red and processed meat intake and mortality among colorectal cancer survivors. J Clin Oncol 31:2773-2782, 2013 6. Yang B, McCullough ML, Gapstur SM, et al: Calcium, vitamin D, dairy products, and mortality among colorectal cancer survivors: The Cancer Prevention Study-II Nutrition Cohort. J Clin Oncol 32:2335-2343, 2014 7. American Institute for Cancer Research/World Cancer Research Fund: Food, Nutrition, Physical Activity and the Prevention of Cancer: A Global Perspective. Washington, DC, American Institute for Cancer Research, 2007 8. Kushi LH, Doyle C, McCullough M, et al: American Cancer Society guidelines on nutrition and physical activity for cancer prevention. CA Cancer J Clin 62:30-67, 2012 9. Pierce JP, Natarajan L, Caan BJ, et al: Influence of a diet very high in vegetables, fruit, and fiber and low in fat on prognosis following treatment for breast cancer: The Women’s Healthy Eating and Living (WHEL) randomized trial. JAMA 298:289-298, 2007 10. Montgomery RK, Krasinski SD, Hirshhorn JN, et al: Lactose and lactase: Who is lactose intolerant and why? J Pediatr Gastroenterol Nutr 45:S131-S137, 2007 11. Crowe FL, Key TJ, Allen NE, et al: The association between diet and serum concentrations of IGF-I, IGFBP-I, IGFBP-2, and IGFBP-3 in the European Prospective Investigation into Cancer and Nutrition. Cancer Epidemiol Biomarkers Prev 18:1333-1340, 2009 12. Gao X, LaValley MP, Tucker KL: Prospective studies of dairy products and calcium intakes and prostate cancer risk: A meta-analysis. J Natl Cancer Inst 97:1768-1777, 2005 13. Qin LQ, Xu JY, Wang PY, et al: Milk consumption is a risk factor for prostate cancer in Western countries: Evidence from cohort studies. Asia Pac J Clin Nutr 16:467-476, 2007
© 2014 by American Society of Clinical Oncology
Downloaded from jco.ascopubs.org on October 21, 2014. For personal use only. No other uses without permission. Copyright © 2014 American Society of Clinical Oncology. All rights reserved.
2291
Editorial
14. Huncharek M, Muscat J, Kupelnick B: Dairy products, dietary calcium and vitamin D intake as risk factors for prostate cancer: A meta-analysis of 26,769 cases from 45 observational studies. Nutr Cancer 60:421-441, 2008 15. Van Loon K, Venook AP: Curable patient with metastatic colorectal cancer: Balancing effective therapies and toxicities. J Clin Oncol 32:991-996, 2014 16. Brett AS: Treating hypercholesterolemia: How should practicing physicians interpret the published data for patients? N Engl J Med 332:676-680, 1989 17. Anderson V: Improving outcomes: Discussing healthy lifestyle choices with your patients. ASCO Connection 19 Dec 2012. https://connection.asco.org/ Magazine/Article/id/3402/Improving-Outcomes-Discussing-Healthy-LifestyleChoices-with-Your-Patients.aspx
18. Huebner J, Marienfeld S, Abbenhardt C, et al: Counseling patients on cancer diets: A critical review of the literature and recommendations for clinical practice. Anticancer Res 34:39-48, 2014 19. Deng GE, Frenkel M, Cohen L, et al: Evidence-based clinical practice guidelines for integrative oncology: Complementary therapies and botanicals. J Soc Integr Oncol 7:85-120, 2009 20. Abrams DI: Integrative oncology: The role of nutrition. In Leser M, Ledesma N, Bergerson S, Trujillo E (eds): Oncology Nutrition for Clinical Practice. Cicago, IL, Oncology Nutrition Dietetic Practice Group of the Academy of Nutrition and Dietetics, 2013, pp 53-60
DOI: 10.1200/JCO.2014.56.6299; published online ahead of print at www.jco.org on June 23, 2014
■ ■ ■
Help Your Patients Learn About Managing the Cost of Cancer Care Do your patients have financial questions about cancer care? Cancer.Net’s Managing the Cost of Cancer Care booklet provides tools and resources that can help your patients answer these questions and plan for costs before, during, and after treatment. Order copies of the booklet for your patients through the ASCO University Bookstore at www.cancer.net/estore. ASCO members receive a 20% discount. The booklet is also available as a downloadable PDF in English and Spanish at cancer.net/managingcostofcare.
2292
© 2014 by American Society of Clinical Oncology
JOURNAL OF CLINICAL ONCOLOGY
Downloaded from jco.ascopubs.org on October 21, 2014. For personal use only. No other uses without permission. Copyright © 2014 American Society of Clinical Oncology. All rights reserved.
