Clinical trial abstracts from Italy, Canada, Turkey, Australia, New Zealand, and China
Coffee as a Prophylaxis Against Liver Cancer
Even those drinking one cup of coffee each day seem to reap significant protection against hepatocellular cancer. Researchers from the Istituto di Ricerche Farmacologiche “Mario Negri,” Milan, Italy, found that among the 10 studies evaluable for the link between coffee consumption and protection from liver cancer, which tested populations ranging from Japan to Southern Europe, the results concurred.
The researchers pointed out, however, that each study defined low, moderate, and high consumers of coffee differently. For example, three cups could be considered low-to-moderate daily consumption in one study but be treated as high daily consumption in another (dependent on the daily number of cups usually drunk by that population). In any case, if a person has only one cup a day, he or she has a 30% lower risk of hepatocellular carcinoma than non—coffee drinkers. If they have higher consumption rates, the risk is 55% less than controls. For each additional one cup per day consumed, the relative risk was 0.77 from the case–control studies evaluated, 0.75 from the cohort studies, and 0.77 overall.
The multivariate-adjusted odds ratios for daily coffee drinkers vs. nondrinkers
Odds of Dying From Liver Cancer
All Coffee Drinkers
HCV-Positive Coffee Drinkers
HCV-Negative Coffee Drinkers
HCV = Hepatitis C virus.
Adapted from Wakai K, Kurozawa Y, Shibata A, et al: Liver cancer risk, coffee, and hepatitis C virus infection: A nested case-control study in Japan. Br J Cancer 2007;97:426-428.
A separate case—control study from Japan found that the odds of dying from hepatocellular cancer in people who were regular coffee drinkers was cut significantly. In fact, the greatest reduction in risk was in patients with hepatitis C virus infection.
Previous reports indicated that heavy coffee consumption may cut colon cancer risk by 50% in women. The basis for a link between coffee and cancer protection is not yet understood, but the weight of evidence is considerable. However, the link between coffee and other cancers may be more insidious (e.g., cervical cancer). Don’t go buying that Starbucks’ stock just yet.
Bravi F, Bosetti C, Tavani A, et al: Coffee drinking and hepatocellular carcinoma risk: A metaanalysis.
Wakai K, Kurozawa Y, Shibata A, et al: Liver cancer risk, coffee, and hepatitis C virus infection: a nested case-control study in Japan.
Hepatology Br J Cancer
Will a Daily Vitamin Prevent Liver Cancer as Well?
Clinical studies are beginning to separate the myths from facts with regard to dietary foods, and vitamin and mineral supplements. Investigators have recently addressed whether some commonly held beliefs about the foods and vitamins we ingest. In late August, a group of researchers from Beijing, China, and the United States participated in a joint randomized, double-blind study to determine whether vitamin or mineral supplements can prevent primary liver cancer.
The study participants included 29,450 healthy adults from Linxian, China. After randomization, the study group was given a vitamin-mineral combination and instructed to take the supplement daily for 5.25 years (ending in May 1991). The supplement contained one of four combinations: (1) retinol and zinc, (2) riboflavin and niacin, (3) ascorbic acid and molybdenum, and (4) beta-carotene, alpha-tocopherol, and selenium, all at doses equal to or twice the U.S. recommended daily allowance. Some patients were randomized to receive all four supplement combinations daily.
After a mean follow-up of approximately 13 years, 151 deaths caused by liver cancer were recorded. The incidence of liver cancer mortality was not different among the overall study groups. The researchers did find some interesting correlations, however. For example, the risk of liver cancer mortality was lower in study participants younger than 55 years at the time of study enrollment who took a combination of retinol and zinc (hazard ratio, 0.59), or riboflavin and niacin (hazard ratio, 0.54). In participants older than 55 years taking the same combinations, the hazard ratio for liver cancer death was actually higher than the control group (hazard ratios, 1.06 and 1.12, respectively).
The investigators concluded that none of these combinations seemed to exert any effect on overall liver cancer mortality; however, there may be some implications for certain subgroups of patients.
Qu C-X, Kamangar F, Fan J-H, et al: Chemoprevention of primary liver cancer: A randomized, double-blind trial in Linxian, China
. J Natl Cancer Inst
A Cost-Effective Method of Screening for Cervical Cancer in Developing Countries
Most of the global incidence of cervical cancer occurs in developing countries, which may account for 85% of the nearly half-million new cases and more than 270,000 deaths recorded annually. The Lancet reports that visual inspection of the cervix using a common chemical agent can be a useful method of diagnosing the disease, particularly in poorer areas.
Research published from the International Agency for Research on Cancer, in Lyon, France, showed that this screening method can reduce the risk of death from cervical cancer by up to 35%.
The investigators screened 31,343 women 30 to 59 years of age without reported health problems from one region in India. The screening method involved the use of a 4% acetic acid solution applied to the cervix. Using a halogen lamp, the technician monitored for the appearance of white lesions. If lesions appeared, the patient was referred for colposcopy, biopsy, or both. A total of 9.8% of the women tested positive by this method. The sensitivity of this screen was 60.7%, with a specificity of 94.0%. Seventy-two percent of the women in whom precancerous lesions were found obtained treatment, and 83 cervical cancer deaths occurred. In a control group of 31,000 women, 92 cervical cancer deaths were recorded.
Based on this research, the authors believe that the use of visual inspection with acetic-acid staining is an effective method of identifying precancerous lesions in developing countries.
Sankaranarayanan R, Esmy PO, Rajkumar R, et al: Effect of visual screening on cervical cancer incidence and mortality in Tamil Nadu, India: A cluster-randomised trial
MULTIPLE SITES IN EUROPE
More Fiber From Cereal, Not Fruits or Vegetables, Proves to Protect from Gastric Cancer
It has long been touted that increasing dietary fiber prevents cancer of the gastrointestinal tract. This association had been shown in the past through case—control studies with fiber obtained from cereal, but evidence had not been published from large prospective studies. One study, with participating centers across Europe, comprises 435,000 subjects and provides some of the best evidence of an association to date.
In this study, the European Prospective Investigation into Cancer and Nutrition Study, volunteers between the ages of 25 and 70 years were surveyed between 1992 and 1998 and were followed for a median 6.7 years.
Three hundred twelve gastric carcinomas were recorded during the follow-up. The analysis of data revealed that greater fiber intake from cereal, but not from fruits or vegetables, was associated with lower risk of gastric cancer, particularly for diffuse tumors (hazard ratio, 0.43). The authors point out that the risk for cardia compared with noncardia tumors was similar to that for overall gastric cancer.
Researchers do not understand why cereal fiber specifically is associated with lower risk of gastric cancer and why intake of fiber from fruits and vegetables was not. However, we now know what manufacturers will soon be printing on the back of our cereal boxes!
Mendez MA, Pera Guillem, Agudo A, et al: Cereal fiber intake may reduce risk of gastric adenocarcinoma: The EPIC-EURGAST study
. Int J Cancer
Tamoxifen Extends Lifein Patients With Advanced Ovarian Cancer in Retrospective Pilot Trial
In patients with advanced epithelial ovarian cancer that is resistant to platinum-containing chemotherapy, survival is poor. Even incremental increases in survival would be important developments for these patients, and an older therapy may be able to deliver on that promise.
A retrospective study was undertaken at Trakya University, Edirne, Turkey, of 29 patients with advanced epithelial ovarian cancer whose disease had progressed despite the use of platinum-containing chemotherapy regimens. These patients were given tamoxifen 20 mg bid, and although 20 (69%) had progressing cancer, the other patients had at least stabilized disease. One patient (3%) demonstrated a complete clinical response. Progression-free survival was six to 12 months for seven patients (24%); Progression- free survival was greater than 12 months for three additional patients (10%). Median survival was 15 months in the entire patient group.
Owing to the lack of better therapies to actively treat advanced ovarian cancer, the investigators believe that these results merit a phase III study of the efficacy of tamoxifen in these patients. Considering the drugs minimal side effect profile, and its ability to bring about objective responses in patients in whom a palliative approach may ordinarily be the next step, tamoxifen treatment may be a useful tool.
Karagol H, Saip P, Uygun K, et al: The efficacy of tamoxifen in patients with advanced epithelial ovarian cancer.
Response to tamoxifen treatment in 29 patients with advanced ovarian cancer that was resistant to platinum-containing chemotherapy regimens.
No Disease Progression
Obesity Predicts Prostate Cancer Recurrence
Researchers have had difficulty in proving a definitive relationship between obesity and the incidence of prostate cancer. Investigators from the British Columbia Cancer Agency in Vancouver have uncovered an intriguing association, however: that obesity is of predictive value for prostate cancer recurrence and survival after radiation therapy.
The researchers followed the progress of 706 men with localized prostate cancer from 1993 to 2001. Each of the study patients was given radiation therapy. The men were stratified by body mass index (195 had a body mass index of < 25 kg/m2; 358 were overweight, and 153 were classified as obese [≥ 30 kg/m2]).
Median time to biochemical recurrence of prostate cancer by body classification.
Time to Recurrence
Normal Weight (< 25 kg/m2)
Overweight (25—29.9 kg/m2)
Obese (≥ 30 kg/m2)
Multivariate analysis revealed that obesity was linked with worse disease-free survival and lower disease-specific survival. The normal weight patients and overweight patients had median 11.1 year disease-specific survivals compared with 10.6 years for the obese weight group. The trend was toward lower overall survival for higher weight class, but this did not reach statistical significance. The authors of this research, published in , also noted that obese men had significantly lower testosterone levels than either the overweight or normal weight patient groups.
Palma D, Pickles T, Tyldesley S, et al: Obesity as a predictor of biochemical recurrence and survival after radiation therapy for prostate cancer
. BJU Int
AUSTRALIA & NEW ZEALAND
Does Medical Immunosuppression Increase the Risk of Ocular Cancer?
It had been documented that patients with human immunodeficiency virus (HIV) infection were at high risk of ocular squamous cell cancer, and this association has now been confirmed in patients who had undergone kidney transplant.
A retrospective analysis of 10,180 recipients of kidney transplants in Australia and New Zealand between 1982 and 2003 revealed five cases of ocular cancer; although this is a small figure, this cancer is so rare that the expected number of cases for this cohort was only 0.26 (an incidence ratio of 19.5). The strongest association found by the researchers was a history of cutaneous squamous cell carcinoma ( = .002). Increased sun exposure also increased the risk (the majority of those developing ocular squamous cell cancer lived in a subtropical environment [ = .04]).
The authors hypothesize that as patients with HIV are certainly immunosuppressed, and patients undergoing renal transplantation take regimens of immunosuppressives to prevent rejection, it may be that the immunosuppressive state is the key toward increasing risk. It would be interesting to conduct further retrospective analysis of patients with other immunosuppressive disorders or those using immunosuppressant medications to determine if the incidence of this rare cancer is increased in a similar manner.
Vajdic CM, van Leeuwen MT, McDonald SP, et al: Increased incidence of squamous cell carcinoma of eye after kidney transplantation.
Sept 5, 2007; E-pub ahead of print.
J Natl Cancer Inst