Role of hormonal risk factors in HER2-positive breast carcinomas

Examination of parity, age at menarche and at menopause by HER2 status in a large series of breast carcinomas showed a statistically significant increased-frequency of HER2-positive tumours in lower risk subgroups. The findings suggest a difference in the protective role of hormone-related risk factors between HER2-positive and -negative tumours.

Mistletoe in cancer - a systematic review on controlled clinical trials

BACKGROUND

Mistletoe preparations are among the most widely used unconventional cancer therapies in Central Europe. Their clinical effectiveness, however, is controversial.

OBJECTIVE

To investigate whether prospective controlled clinical trials provide evidence for efficacy of mistletoe therapy in cancer.

DESIGN

Systematic review.

MATERIAL AND METHODS

Search of 11 electronic databases, reference lists and expert consultations. Criteria based analysis was performed to assess methodological quality of the studies.

RESULTS

Twenty-three studies were identified: 16 randomized, 2 quasi-randomized and 5 non-randomized. Cancer sites included breast, lung, stomach, colon, rectum, head and neck, kidney, bladder, melanoma, glioma, and genital. Among these studies, statistically significant positive outcomes were reported for survival (n = 8), tumor remission (n = 1), overall quality of life (QOL) (n = 3), and QOL in relation to side effects during cytoreductive therapy (n = 3). Further, positive trends were reported for survival (n = 8), disease-free-survival (n = 1), and tumor remission (n = 2). Several studies reported no effect on survival (n = 4), disease-free-survival (n = 1), recurrence (n = 2), remission (n = 3), and QOL (n = 1). One study showed a negative trend for disease-free-survival. However, methodological quality of the studies was sometimes far below the standard that is today regarded as optimal or necessary. In view of substantial heterogeneity of the studies and potential positive and negative biases, we considered effect size estimation by quantitative synthesis to be unreliable and decided on a non-quantitative synthesis and discussion. Mistletoe therapy was well tolerated, and no major side effects were noted.

CONCLUSIONS

Among 23 identified studies evaluated for clinically relevant outcome measures, 12 studies showed one or more statistically significant, positive results, another 7 studies showed at least one positive trend, 3 showed no effect and 1 had a negative trend. All studies, however, suffered from methodological shortcomings to some degree, and many of the studies are not conclusive. As several reasonably well conducted studies indicate beneficial effects, further properly designed trials should be encouraged. Future controlled studies should take into account the methodological limitations and potential biases of these past mistletoe trials.

Consumption of dairy products in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort: data from 35 955 24-hour dietary recalls in 10 European countries

OBJECTIVES

To describe and compare the consumption of dairy products in cohorts included in the European Prospective Investigation into Cancer and Nutrition (EPIC).

METHODS

Data from single 24-hour dietary recall interviews collected through a highly standardised computer-based program (EPIC-SOFT) in 27 redefined centres in 10 European countries between 1995 and 2000. From a total random sample of 36 900, 22 924 women and 13 031 men were selected after exclusion of subjects under 35 and over 74 years of age.

RESULTS

A high total consumption of dairy products was reported in most of the centres in Spain and in the UK cohort sampled from the general population, as well as in the Dutch, Swedish and Danish centres. A somewhat low consumption was reported in the Greek centre and in some of the Italian centres (Ragusa and Turin). In all centres and for both sexes, milk constituted the dairy sub-group with the largest proportion (in grams) of total dairy consumption, followed by yoghurt and other fermented milk products, and cheese. Still, there was a wide range in the contributions of the different dairy sub-groups between centres. The Spanish and Nordic centres generally reported a high consumption of milk, the Swedish and Dutch centres reported a high consumption of yoghurt and other fermented milk products, whereas the highest consumption of cheese was reported in the French centres.

CONCLUSION

The results demonstrate both quantitative and qualitative disparities in dairy product consumption among the EPIC centres. This offers a sound starting point for analyses of associations between dairy intake and chronic diseases such as cancer.

Cancer prevalence in European registry areas

BACKGROUND

Information on cancer prevalence is of major importance for health planning and resource allocation. However, systematic information on cancer prevalence is largely unavailable.

MATERIALS AND METHODS

Thirty-eight population-based cancer registries from 17 European countries, participating in EUROPREVAL, provided data on almost 3 million cancer patients diagnosed from 1970 to 1992. Standardised data collection and validation procedures were used and the whole data set was analysed using proven methodology. The prevalence of stomach, colon, rectum, lung, breast, cervix uteri, corpus uteri and prostate cancer, as well as of melanoma of skin, Hodgkin's disease, leukaemia and all malignant neoplasms combined, were estimated for the end of 1992.

RESULTS

There were large differences between countries in the prevalence of all cancers combined; estimates ranged from 1170 per 100000 in the Polish cancer registration areas to 3050 per 100000 in southern Sweden. For most cancers, the Swedish, Swiss, German and Italian areas had high prevalence, and the Polish, Estonian, Slovakian and Slovenian areas had low prevalence. Of the total prevalent cases, 61% were women and 57% were 65 years of age or older. Cases diagnosed within 2 years of the reference date formed 22% of all prevalent cases. Breast cancer accounted for 34% of all prevalent cancers in females and colorectal cancer for 15% in males. Prevalence tended to be high where cancer incidence was high, but the prevalence was highest in countries where survival was also high. Prevalence was low where general mortality was high (correlation between general mortality and the prevalence of all cancers = -0.64) and high where gross domestic product was high (correlation = +0.79). Thus, the richer areas of Europe had higher prevalence, suggesting that prevalence will increase with economic development.

CONCLUSIONS

EUROPREVAL is the largest project on prevalence conducted to date. It has provided complete and accurate estimates of cancer prevalence in Europe, constituting essential information for cancer management. The expected increases in prevalence with economic development will require more resources; allocation to primary prevention should therefore be prioritised.

Effects of transportation and delay in processing on the stability of nutritional and metabolic biomarkers

The effects of transportation and delay in processing of blood samples on the concentration of biomarkers are significant in epidemiological studies for which specimens are collected from participants at locations other than a designated center or laboratory. These sources of variability in measurement were studied by collecting two sets of blood samples from 51 men between 26 and 50 years of age. The first set was sent immediately to the laboratory for processing. The second set was transported by car for one hour and then returned to the laboratory for processing. Both sets were stored together at -80 degrees C until the end of the study. Several blood constituents were evaluated. Vitamins, liver enzymes, and electrolytes showed no changes in concentration after transport by car for one hour. There were decreases in the concentrations of red and white blood cells, high-density-lipoprotein cholesterol, glucose, and creatinine after transportation. The transported total cholesterol, total testosterone, free testosterone, alkaline phosphatase, total bilirubin, and thiobarbituric acid-reactive substances increased in concentration. Although transportation and delay in processing of blood samples do not appear to greatly impact relative risk estimates, epidemiologists should be aware of these potential sources of variability in measurement and consider the consequences in their particular study.

Cancer survival increases in Europe, but international differences remain wide

The EUROCARE project analysed cancer survival data from 45 population-based cancer registries in 17 European countries, revealing wide international differences in cancer survival. We calculated 5-year relative survival for 1836287 patients diagnosed with one of 13 cancers during the period 1978-1989. The data, from 20 cancer registries in 13 countries, were grouped into four regions: Finland, Sweden, Iceland (Northern Europe); Denmark, England and Scotland (UK and Denmark); France, The Netherlands, Germany, Italy and Switzerland (Western Europe); Estonia and Poland (Eastern Europe), and broken down into four periods (1978-1980, 1981-1983, 1984-1986, 1987-1989). For each cancer, mean European and regional survival was estimated as the weighted mean of 5-year relative survival in each country. Survival increased with time for all tumours, particularly for cancers of testis (12% increase, i.e. from 79.9 to 91.9%), breast, large bowel, skin melanoma (approximately 9-10%), and lymphomas (approximately 7%). For most solid tumours, survival was highest in Northern Europe and lowest in Eastern Europe, and also low in the UK and Denmark. Regional variation was less marked for the lymphomas. Survival improved more in Western than Northern Europe, and the differences between these regions fell for bowel cancer (from 8.0% for those diagnosed in 1978-1980 to 2% for those diagnosed in 1987-1989), breast cancer (from 7.4% to 3.9%), skin melanoma (from 13.4% to 11.0%) and Hodgkin's disease (from 7.2 to 0.6%). For potentially curable malignancies such as Hodgkin's disease, large bowel, breast and testicular cancers, there were substantial increases in survival, suggesting an earlier diagnosis and more effective treatment. The persisting regional differences suggest there are corresponding differences in the availability of diagnostic and therapeutic facilities, and in the effectiveness of healthcare systems.

Assay of erythrocyte membrane fatty acids. Effects of storage time at low temperature

The study of the stability of saturated mono-, or polyunsaturated fatty acids, both esterified and not esterified, in plasma, circulating cells, and tissues is extremely important to validate the use of biological samples stored at low temperature in "biological banks", which are used for experimental, observational, dietary, or pharmacological studies. Since red blood cells are easily accessible cells, they are used as a marker of less-accessible tissues, especially in large-scale epidemiological studies. Data from the literature suggest that the addition of an antioxidant and the freezing of red blood cells do not cause any variation in the fatty acid composition for a period of 2-6 months up to 1 year. We evaluated the fatty acid concentration in red blood cells isolated from venous blood samples of one subject, preserved with butylated hydroxytoluene and N2 and stored at -80 degrees C for up to 2 years. Erythrocytes of venous samples of six subjects stored at -20 degrees C for 6 months without butylated hydroxytoluene and in the presence of air were used for comparison purposes. Our data demonstrate that a long storage time (2 years) does not significantly influence the erythrocyte fatty acid concentration when using very low temperatures (-80 degrees C) and antioxidants (butylated hydroxytoluene) in the presence of N2.

Erythrocyte membrane fatty acids and subsequent breast cancer: a prospective Italian study

BACKGROUND

The relationship between erythrocyte membrane fatty acids and postmenopausal breast cancer risk was analyzed previously only by retrospective studies, which suggested a protective effect of increased saturation index (SI), i.e., the ratio of membrane stearic to oleic acid. We investigated the relationships in a prospective study of hormones, diet, and prediagnostic breast cancer (the ORDET study) conducted in northern Italy.

METHODS

A total of 4052 postmenopausal women were followed for an average of 5.5 years; 71 cases of invasive breast cancer were identified. For each case subject, two matched control subjects were chosen randomly from among cohort members. The various fatty acids in erythrocyte membranes were measured as a percentage of total fatty acids. Conditional logistic regression analysis evaluated the association between membrane fatty acid composition and breast cancer risk. The SI, which is influenced by the activity of the enzyme delta 9 desaturase (Delta 9-d), was also investigated. All statistical tests were two-sided.

RESULTS

Oleic (highest versus lowest tertile of percentage of total fatty acids, odds ratio [OR] = 2.79; 95% confidence interval [CI] = 1.24 to 6.28) and monounsaturated fatty acids (highest to lowest tertile, OR = 5.21; 95% CI = 1.95 to 13.91) were positively associated with breast cancer risk. The SI (highest to lowest tertile, OR = 0.29; 95% CI = 0.13 to 0.64) was inversely associated with breast cancer risk. The analysis suggested an inverse association between total polyunsaturated fatty acids and breast cancer risk, but individual polyunsaturated fatty acids behaved differently. There was no association between saturated fatty acids and breast cancer risk.

CONCLUSIONS

We have found that monounsaturated fats and SI in erythrocyte membranes are predictors of postmenopausal breast cancer. Both of these variables depend on the activity of the enzyme Delta 9-d. The dietary, metabolic, and hormonal factors acting on Delta 9-d expression and activity and, therefore, on patterns of fatty acid metabolism, should be further investigated as possible determinants of breast cancer.

Incidence and prevalence of all cancerous diseases in Italy

The burden of cancer in ageing populations is causing great concern, particularly in Italy with Europe's fastest growing elderly population. Studying all cancers combined in one group, although of limited medical value, is of great interest from the viewpoints of public health, epidemiology and the economy. Using mortality data and an estimate of cancer patients' survival we have estimated and projected incidence and prevalence in Italy of all cancers combined in one group. Five major phenomena are highlighted in the paper: (1) the decrease in the age-adjusted cancer mortality rates among females and the stable mortality rates among males since 1990; (2) the changing pattern of cancer incidence since 1990, it has started to decrease for females and is stabilising for males; (3) the decrease in cancer incidence among males and females born after 1940; (4) the increase in the proportion of cancer patients that are cured with calendar years of diagnosis; (5) the increase in the total and the healthy life expectancy (i.e. cancer-free) among the Italian population since 1970. The declining and flat trends in age-adjusted cancer incidence and mortality rates since 1990 is the combined effect of survival improvements and cancer risk reduction for younger cohort groups, after 1940. These favourable trends contribute to the increase in healthy life expectation, thus supporting the idea that we live longer and healthier.

Survival of children with malignant germ cell, trophoblastic and other gonadal tumours in Europe

Collaborators of the EUROCARE study had provided records on 1263 cases of germ cell, trophoblastic and other gonadal neoplasms, registered in 34 cancer registries in 16 European countries over the period 1978--1992 and followed-up until the end of 1994. Observed 5-year actuarial survival for 490 cases diagnosed in 1985-1989 was 80% (95% confidence interval (CI)=(76, 83)). The corresponding figures were calculated for the intracranial and intraspinal germ cell tumours (68%, 95% CI=(57, 76)), other non-gonadal germ cell tumours (76%, 95% CI=(68, 82)), gonadal germ-cell tumours (89%, 95% CI=(85, 93)) and gonadal carcinomas (50%, CI=(24, 76)). Relatively large differences in survival were observed between age-sex subgroups, which also differed with histology, with extremely poor survival of young children with intracranial and intraspinal germ cell tumours. Lower survival was observed in the countries with formerly socialist economies. Time trends in survival were examined for the entire study period, including only the cases registered in the large contributing registries. For all germ cell tumours, the risk ratios calculated in the Cox regression analysis were markedly lowered for the years after the reference period of 1978--1981. The improved outcome is attributed to treatment advances.

Variation in survival of children with central nervous system (CNS) malignancies diagnosed in Europe between 1978 and 1992: the EUROCARE study

EUROCARE is a population-based survival study including data from European Cancer Registries. The present paper analyses survival after a malignant neoplasm of the central nervous system (CNS) in childhood (aged 0--14 years at diagnosis). The database includes 6130 cases from 34 population-based registries in 17 countries: 1558 were primitive neuroectodermal tumours (PNET) and 4087 astrocytoma, ependymoma or other gliomas: these morphologies were grouped in the analyses in order to reduce the diagnostic variability among the registries. 87% of cases were microscopically diagnosed (range among registries 71--100%) and losses to follow-up were limited to 2% (range 0--14%). Actuarial analyses indicate that the European (weighted) average of 5 years cumulative survival for cases diagnosed in 1978--1989 was 53% (95% confidence interval (CI) 49--57) for CNS neoplasms, 44% (95% CI 37--50) for PNET and 60% (95% CI 55--65) for the glioma-related types. Analysis of the sub-set of cases diagnosed in 1985--1989 revealed better results: cumulative survival at 5 years was 61% (95% CI: 55--65) for all CNS neoplasms; 48% (95% CI 41--56) for PNET and 68% (95% CI 62--73) for glioma-related types. Compared with older children, infants showed poorer prognosis: in 1978--1989 the 5-year survival rate was 33% (95% CI 23--45) and in 1985--1989 it was 46% (95% CI 34--59). Variability among countries was very large, with 5-year survival for CNS tumours diagnosed in 1985--1989 ranging from 28% in Estonia (95% CI 17--43) to 73% Sweden (95% CI 59--83) and 75% in Iceland (95% CI 35--95) and 73% in Finland (95% CI 66--79). Time trends were studied in a multivariate analysis observing a reduction in the risk of death in periods of diagnosis 1982--1985 (hazard ratio (HR)=0.85; 95% CI 0.78--0.93) and 1986--1989 (HR=0.70; 95% CI 0.64--0.77) compared with 1978--1981. The analysis were extended to 1990--1992 for the countries whose registries provided data for that period did not indicate any further progress. Results of this study confirm the large variability in European countries and indicate a positive trend in the survival probability for cases diagnosed in the 1980s.

Reducing bioavailable sex hormones through a comprehensive change in diet: the diet and androgens (DIANA) randomized trial

High serum levels of testosterone and estradiol, the bioavailability of which may be increased by Western dietary habits, seem to be important risk factors for postmenopausal breast cancer. We hypothesized that an ad libitum diet low in animal fat and refined carbohydrates and rich in low-glycemic-index foods, monounsaturated and n-3 polyunsaturated fatty acids, and phytoestrogens, might favorably modify the hormonal profile of postmenopausal women. One hundred and four postmenopausal women selected from 312 healthy volunteers on the basis of high serum testosterone levels were randomized to dietary intervention or control. The intervention included intensive dietary counseling and specially prepared group meals twice a week over 4.5 months. Changes in serum levels of testosterone, estradiol, and sex hormone-binding globulin were the main outcome measures. In the intervention group, sex hormone-binding globulin increased significantly (from 36.0 to 45.1 nmol/liter) compared with the control group (25 versus 4%,; P < 0.0001) and serum testosterone decreased (from 0.41 to 0.33 ng/ml; -20 versus -7% in control group; P = 0.0038). Serum estradiol also decreased, but the change was not significant. The dietary intervention group also significantly decreased body weight (4.06 kg versus 0.54 kg in the control group), waist:hip ratio, total cholesterol, fasting glucose level, and area under insulin curve after oral glucose tolerance test. A radical modification in diet designed to reduce insulin resistance and also involving increased phytoestrogen intake decreases the bioavailability of serum sex hormones in hyperandrogenic postmenopausal women. Additional studies are needed to determine whether such effects can reduce the risk of developing breast cancer.