The American Association for Cancer Research (AACR) held its annual meeting in San Diego, California, April 5-9, 2014. Presentations at this meeting are typically focused on new research in therapeutics and epidemiology. Below are brief reports on some highlights from the meeting related to cancer risk and health-related behaviors.
Irregular Menses and Ovarian Cancer
The first prospective study to link reproduction to ovarian cancer risk found that a history of irregular menstrual cycles at age 26 years predicted the eventual development of aggressive ovarian cancer. In fact, women with irregular menses had as high as a 2-fold increase in the risk of ovarian cancer and a more than 2-fold increase in the risk of ovarian cancer death.
These findings are important, said lead author Barbara A. Cohn, PhD, MPH, of the Public Health Institute in Berkeley, California, because by the time most ovarian cancers are detected, they are already symptomatic and aggressive. “These data are the first solid lead we’ve had that has potential for earlier diagnosis. This is an opportunity to identify underlying mechanisms and ways to prevent the 90% of sporadic ovarian cancers that occur without known heritable risk,” she added.
“The devil is in the details,” Cohn said. “We defined ‘irregular’ as cycles longer than 35 days or anovulatory menstrual cycles. In other words, these women could not predict when their menses was coming.”
The study enrolled only pregnant women in order to rule out the effect of fertility drugs and infertility on the risk of developing ovarian cancer. As part of the Child Health and Development Studies, 14,403 pregnant women were recruited from 1959 to 1967. At baseline (median age, 26 years), women were asked to characterize their menstrual cycles. Thirteen percent reported irregular menses according to the definition Cohn described. These data were linked to California Vital Statistics and National Death Index files to detect 103 cases of ovarian cancer, histology, stage, grade, and mortality (there were 65 deaths).
Women with irregular cycles had a 37% increased risk of developing ovarian cancer and more than a 2-fold increase in ovarian cancer death due to more late-stage disease and more aggressive histology at diagnosis. The risk was greatest for late-stage, high-grade, and serous tumors, Cohn said.
In the overall analysis, irregular menses was associated with a 2.3 times greater risk of ovarian cancer death (P = .01) and a 3 times greater risk of death from late-stage serous ovarian cancer (P = .01). The risk of developing late-stage or high-grade serous ovarian cancer was also significantly increased among women with a history of irregular menses (P = .02 and P = .07, respectively).
Although these findings are hypothesis generating, Cohn said that young women with irregular menses might consider taking birth control pills. “Birth control pills seem to be protective and regularize menstrual cycles. Of course, this decision should be made in consultation with a physician, and individual risk factors need to be considered as well,” Cohn noted.
ReferenceCohn BA, Cirillo PM, Wang ET, et al. Irregular menstruation predicts increased risk of subsequent ovarian cancer death in a prospective cohort, The Child Health and Development Studies. Presented at: 2014 Annual Meeting of the American Association for Cancer Research; April 5-9, 2014; San Diego, CA. Abstract LB-277.
Jump-Starting Smoking Cessation for Cancer Patients
To commemorate the 50th anniversary of the US Surgeon General’s report on the dangers of tobacco, the AACR published a policy statement on tobacco use by cancer patients to coincide with its 2014 annual meeting. Scientific evidence shows that tobacco use in cancer patients leads to poorer outcomes by compromising response to therapy, increasing treatment-related toxicity, increasing the risk of recurrence and second primary tumors, and hastening earlier death. Yet a certain proportion of patients continues to smoke.
The policy statement emphasizes the need to integrate evidence-based tobacco-dependence treatment into all healthcare delivery. At the present time, there is a scarcity of dedicated cessation treatment programs available at oncology practices.
The statement emphasizes that the “5 A’s” program developed by the US Department of Health and Human Services is a proven method of increasing rates of successful quitting. This model relies on the following steps: ASK about tobacco use at every clinic visit; ADVISE to quit; ASSESS interest in quitting; ASSIST by providing counseling and pharmacotherapy; and ARRANGE follow-up. Although the “5 A’s” model lacks an evidence base for patients with cancer, following this model could be instrumental in helping cancer patients to quit smoking.
Surveys of oncologists and other healthcare providers show that smoking cessation is rarely offered to patients, even though most agree that tobacco affects cancer outcomes and should be part of cancer care. In one survey of members of the International Association for the Study of Lung Cancer, more than 90% of respondents said this was important, yet only 40% discussed medications or provided any type of cessation support. Many respondents indicated the perceived inability to get patients to quit using tobacco as well as patient resistance to intervention programs were the main barriers to offering cessation support.
AACR made 2 recommendations: (1) Patients with cancer who use tobacco or who have quit within the past 30 days should be provided with evidence-based tobacco-cessation assistance, ideally within or associated with the oncology practice; and (2) Tobacco use should be comprehensively and repeatedly documented for all patients so that the confounding effects of tobacco on cancer treatment, disease progression, comorbid events, and survival can be evaluated in clinical trials and in all cancer settings.
ReferenceToll BA, Brandon TH, Gritz ER, et al; Writing Committee for the AACR Subcommittee on Tobacco and Cancer. Assessing tobacco use by cancer patients and facilitating cessation: an American Association for Cancer Research policy statement. Clin Cancer Res. 2013;19(8):1-8. http://www.aacr.org/Uploads/DocumentRepository/LegAffairs/Tobacco/AACRStatement_TobaccoUseCancerPatients_2013_CCR.pdf. Accessed April 16, 2014.
Coffee Intake May Reduce Risk of Hepatocellular Carcinoma
Increased consumption of coffee was associated with reduced risk of developing hepatocellular carcinoma (HCC), the most common type of liver cancer.1 A significant dose response was observed, noted lead author V. Wendy Setiawan, PhD, of the USC Norris Comprehensive Cancer Center in Los Angeles, California.
People who drank between 1 to 3 cups of coffee per day had a 29% reduced risk of HCC, while those who drank 4 or more cups per day had a 42% lower risk. The researchers did not look at the effect of consumption of decaffeinated coffee.
“Previous studies showed that coffee lowers the risk of HCC, but these studies were conducted outside of the US. We wanted to examine whether coffee consumption was associated with risk of HCC in multiethnic US populations,” she said.
The study was based on a prospective analysis of approximately 180,000 men and women, including 52,548 Japanese Americans, 45,641 Caucasians, 39,097 Latinos, 29,486 African Americans, and 13,118 Native Hawaiians. Data were collected on coffee consumption and other lifestyle factors, and people were followed for up to 18 years. HCC developed in 498 participants: 171 Japanese Americans, 67 Caucasians, 153 Latinos, 73 African Americans, and 34 Native Hawaiians.
The relationship between coffee consumption and lower risk of HCC was independent of ethnicity, gender, body mass index, smoking status, alcohol intake, and diabetes status. Also, in a subset analysis of participants with available hepatitis B and hepatitis C serologic status, the association between coffee consumption and HCC was independent of hepatitis infections. Setiawan and colleagues plan to study the association between coffee consumption and incidence and mortality with chronic liver diseases across multiethnic groups.
A related study showed that increased coffee intake was also associated with reduced risk of melanoma.2 Participants who consumed 4 or more cups of coffee per day had a 20% reduction in the risk of melanoma compared with non-coffee drinkers. No association was observed for decaffeinated coffee.
The study analyzed data from the large, prospective NIH-AARP Diet and Health Study. Coffee intake was assessed at baseline with a food intake questionnaire.
Among 447,357 non-Hispanic whites who were cancer-free at baseline, 2904 developed melanoma during 4,329,044 person-years of follow-up. Respondents were followed from baseline until the date of first skin cancer diagnosis, the date of death, the end of study follow-up, or moving out of a catchment area (whichever occurred first).
The analysis was adjusted for multiple potential confounders for melanoma risk in relationship to level of coffee intake. Lead author Erikka Loftfield, MPH, of the National Cancer Institute, said that additional study of caffeine and other coffee constituents is warranted in the prevention of melanoma.
References1. Setiawan VW, Wilkens LR, Hernandez BY, et al. Coffee intake reduces hepatocellular carcinoma risk: the Multiethnic Cohort. Presented at: 2014 Annual Meeting of the American Association for Cancer Research; April 5-9, 2014; San Diego, CA. Abstract LB-281.2. Loftfield E, Mayne S, Shebl F, et al. Prospective study of coffee drinking and risk of melanoma in the United States. Presented at: 2014 Annual Meeting of the American Association for Cancer Research; April 5-9, 2014; San Diego, CA. Abstract LB-280.
Obesity Linked to Poor Outcome in Colorectal Cancer
Yet another study points out the dangers of obesity, in this case the relationship of prediagnosis obesity to poor outcomes for people with colorectal cancer. In fact, the presence of prediagnosis obesity trumped high microsatellite instability (MSI), a tumor marker usually associated with better outcomes.
“We know that increased body mass index [BMI] is associated with a variety of poor health outcomes, including poor prognosis in survivors of breast and endometrial cancers. One of the clearest associations is with colorectal cancers. The timing of obesity is important, because increased BMI measured before diagnosis is predictive. After diagnosis, BMI is no longer predictive because patients get sick and lose weight,” explained lead author Peter T. Campbell, PhD, director of the Tumor Repository in the Epidemiology Research Program at the American Cancer Society in Atlanta, Georgia.
“This study, to my knowledge, is the first study with sufficient numbers to investigate how these independent risk factors work together to influence survival after a colorectal cancer diagnosis. We found that a high prediagnosis BMI is associated with increased all-cause and colorectal cancer–specific mortality after diagnosis. We also found that high BMI overrides the survival advantage conferred by an MSI-high tumor,” he said.
“The take-home message is that BMI is prognostic. At the highest level (BMI >40 kg/m2), colorectal cancer mortality was increased by 48%. This is another reason to maintain lower body weight,” Campbell stated.
The study was based on 6763 patients with invasive colorectal cancer who enrolled in the Colon Cancer Family Registry from 1997 to 2008. BMI 2 years prior to diagnosis and at age 20 years and adult weight gain were calculated from self-reports of height and weight. Tumor MSI status was available for 4987 patients. Median follow-up was 5.3 years.
For every 5 kg/m2 increase in BMI, there was a 10% increase in all-cause mortality. For patients with MSI-high and MSI-stable/MSI-low tumors, every 5 kg/m2 increase in BMI increased all-cause mortality by 19% and 8%, respectively.
A similar pattern was observed for the association between increased BMI and colorectal cancer–specific mortality as well, with the risk of colorectal cancer–specific mortality increasing by 7% for every 5 kg/m2 increase in BMI.
“This study is unique because we looked at the joint impact of BMI and MSI. Obesity removes the net benefit of high MSI,” Campbell emphasized.
He and his colleagues are planning to look at the association between prediagnosis obesity and other tumor markers implicated in colorectal cancer survival. The ultimate goal is to investigate the association between obesity and somatic tumor mutations to determine how obesity may drive cancer, Campbell noted.
ReferenceCampbell PT, Newton C, Newcomb PA, et al. Prospective study of body mass index and adult weight change with colorectal cancer survival, overall and by tumor microsatellite instability status. Presented at: 2014 Annual Meeting of the American Association for Cancer Research; April 5-9, 2014; San Diego, CA. Abstract LB-276.
To sign up for our newsletter or print publications, please enter your contact information below.
