Role of diet in cancer incidence in Hawaii
Incidence rates for many sites of cancer show wide variations among the main ethnic groups in Hawaii (Caucasians, Japanese, Chinese, Filipinos, and Hawaiians). Major shifts in cancer rates among migrants to the islands suggest that environmental factors are at least in part responsible for these variations. One prominent area of difference among these ethnic populations is their diets, which can vary substantially, not only in the consumption of particular food items but also in mean nutrient intakes. In aggregate correlational analyses based on data from representative samples of these ethnic groups and corresponding population-based cancer incidence rates, we found significant associations between ethnic-sex-specific intakes of dietary fat (including total fat, as well as animal, saturated, and unsaturated fats) and breast, endometrial, and prostate cancers. Animal protein intake showed associations similar to those for dietary fat, but these two nutrients were highly correlated in the data. Cholesterol intake showed significant correlations with lung and laryngeal cancers. Analyses of both nutrient and food item data suggested an association of stomach cancer incidence with the consumption of fish products, particularly dried/salted fish, and with a lower intake of vitamin C. Preliminary findings from ongoing case-control studies showed the following relationships: an inverse association between lung cancer risk and the intake of food sources of vitamin A, especially foods containing carotenes; an inverse association between cancers of the lower urinary tract and vitamin A consumption, especially from supplements; a positive association between prostate cancer risk and dietary fat intake in men above age 69, but not in younger men; and a positive association between breast cancer risk and the intake of dietary fat (particularly saturated fat) and animal protein in postmenopausal women, especially the Japanese. Two large cohorts (50,000 and 5,000 subjects) on whom dietary information was collected between 1975 and 1980 are being followed prospectively for their occurrence of cancer. [1]
Cancer incidence among Finnish workers exposed to halogenated hydrocarbons
Epidemiologic studies and long-term carcinogenicity studies in experimental animals suggest that some halogenated hydrocarbons are carcinogenic. To investigate whether exposure to trichloroethylene, tetrachloroethylene, or 1,1,1-trichloroethane increases carcinogenic risk, a cohort of 2050 male and 1924 female workers monitored for occupational exposure to these agents was followed up for cancer incidence in 1967 to 1992. The overall cancer incidence within the cohort was similar to that of the Finnish population. There was an excess of cancers of the cervix uteri and lymphohematopoietic tissues, however. Excess of pancreatic cancer and non-Hodgkin lymphoma was seen after 10 years from the first personal measurement. Among those exposed to trichloroethylene, the overall cancer incidence was increased for a follow-up period of more than 20 years. There was an excess of cancers of the stomach, liver, prostate, and lymphohematopoietic tissues combined. Workers exposed to 1,1,1-trichloroethane had increased risk of multiple myeloma and cancer of the nervous system. The study provides support to the hypothesis that trichloroethylene and other halogenated hydrocarbons are carcinogenic for the liver and lymphohematopoietic tissues, especially for non-Hodgkin lymphoma. The study also documents excess of cancers of the stomach, pancreas, cervix uteri, prostate, and the nervous system among workers exposed to solvents. [2]
The contribution of inherited predisposition to cancer incidence
Only a small proportion of cancers, arising in inherited syndromes such as polyposis coli, have an unequivocally inherited basis. Nevertheless, most common cancers show familial clustering, much of which may be due to inherited predisposition. If so, there may be wide variation in genetic susceptibility to common cancers. The precise models of susceptibility are unclear, but for ovarian cancer and breast cancer there is some evidence that a small proportion of cases result from highly penetrant dominant genes. This has been confirmed recently for breast cancer by genetic linkage studies. Clear evidence for genetic susceptibility has been obtained for Hodgkin’s disease and nasopharyngeal carcinoma, where the existence of susceptibility genes at the HLA locus has been demonstrated by linkage analysis. These genes could account for the majority of cases of these cancers. Identification of other cancer susceptibility genes should be possible, either directly using linkage analysis, or through identification of constitutional phenotypes related to cancer risk. [3]
Prostate Cancer Incidence in Calabar – Nigeria
Aim: The aim of this study is to determine the incidence of prostate cancer in men living in Calabar- Nigeria, which has not been determined up till now.
Study Design: A trend analysis of prostate cancer cases in Calabar between 1st January 2004 to 31st December 2013.
Place and Duration of Study: Calabar cancer registry, May to June 2015.
Methodology: Record of prostate cancer cases in the Calabar cancer registry between 1st January 2004 and 31st December 2013,was accessed. The patients age, sex, place domiciled in the last one year; whether rural or urban as well as prostate cancer topography and morphology were obtained and analyzed. The population of males domiciled in Calabar was determined using the 2006 national population census data and 3.0% population growth as specified by the national population commission. Excluded are all male genital tract cancers outside prostate cancer .The data was subjected to statistical analysis using SPSS version 21.
Results: Two hundred and seventy nine (279) prostate cancer cases were seen, with mean (SD) age of subjects being 64.2 (9.5) years, with a range 40 to 95 years. About 249 cases (89.3%) occurred in those who are 55 years or older at time of diagnosis, with the commonest age group being 60-64 years. The age specific incidence of prostate cancer is 89 per 100,000, both crude and adjusted incidence rates were highest in 2012 (69.4 and 97.4 per 100,000, respectively). There was significant decrease in incidence rates in the initial five years (2004-2008), and increase in rates in the following five years of study (2009-2013). Within the 5-year period from 2004 to 2008, there was an average annual decrease in incidence rate of 9.63% (95% CI: 6.1%-12.8%). However, within the 5-year period from 2009 to 2013, there was an average annual increase in incidence rate of 11.95% (95%CI: 8.72% to 13.04%).
Conclusion: This epidemiologic study demonstrate the incidence of prostate cancer in Calabar, Nigeria, with a predominance of patients in the 60- 64 years age group. West African states have to scale up population screening and study of this neoplasm. [4]
Socioeconomic and Age-incidence of Breast Cancer: Modeling Using Artificial Intelligence Technique
Purpose: The majority of women presenting with breast cancer it are not possible to identify specific risk factors. Age is the major factor on breast cancer incidence. Also, poverty status can be classified. Because of the weakness of the underlying empirical data in many countries, a number of the indicators presented here are associated with significant uncertainty. The fuzzy logic inference method as an artificial intelligence technique is proposed for modeling data.
Methods: In our situation it is very difficult to use classical logic to model a system with the available knowledge. Classical logic does not allow working with uncertainty in the information when knowledge about the behavior of the systems is imprecise. A fuzzy system was constructed with three inputs parameters and one output expressing the number of cases.
Results: The result of the fuzzy program so far, is a numeric and symbolic terms of number of breast cancer recorded; using the fuzzy inputs data in the universe of discourse (poor, near poor or non-poor), age and period.
Conclusion: Once the established system, it allows to predict the impact of each input and its effect on the output parameter. Assessing the degree of impact allows us to define the set the factor that has the greatest impact in the fight against breast cancer. The result is the contribution of the set of input variable, taking into account inaccuracies and the complexity involved in the process. [5]
Reference
[1] Kolonel, L.N., Nomura, A.M., Hinds, M.W., Hirohata, T., Hankin, J.H. and Lee, J., 1983. Role of diet in cancer incidence in Hawaii. Cancer research, 43(5 Suppl), pp.2397s-2402s.
[2] Anttila, A., Pukkala, E., Sallmén, M., Hernberg, S. and Hemminki, K., 1995. Cancer incidence among Finnish workers exposed to halogenated hydrocarbons. Journal of Occupational and Environmental Medicine, 37(7), pp.797-806.
[3] Easton, D.O.U.G.L.A.S. and Peto, J.U.L.I.A.N., 1990. The contribution of inherited predisposition to cancer incidence. Cancer Surveys, 9(3), pp.395-416.
[4] Ebughe, G. A., Ekanem, I. A., Omoronyia, O. E., Nnoli, M. A., Ikpi, E. E. and Ugbem, T. I. (2016) “Prostate Cancer Incidence in Calabar – Nigeria”, Journal of Advances in Medicine and Medical Research, 14(5), pp. 1-10. doi: 10.9734/BJMMR/2016/23503.
[5] Bouharati, K., Hamdi-Cherif, M., Mahnane, A., Laaouamri, S., Bouaoud, S., Boukharouba, H., Bouharati, O., Boucenna, N. and Bouharati, S. (2016) “Socioeconomic and Age-incidence of Breast Cancer: Modeling Using Artificial Intelligence Technique”, Journal of Cancer and Tumor International, 3(3), pp. 1-8. doi: 10.9734/JCTI/2016/24774.
