• Asian Pacific Journal of Cancer Prevention
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• 제15권22호
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• pp.9859-9863
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• 2014

Genetic epidemiological studies have shown that genetic susceptibility to esophageal cancer (EC) is an important cause of its high incidence within families in some areas of China. The purpose of this study was to obtain evidence of a genetic basis of EC in Xin-an and Xin-xiang counties in China. Familial aggregation and complex segregation analyses were performed of 79 EC families in these counties. The heritability of EC was examined using Falconer's method and complex segregation analysis was conducted with the SEGREG program in Statistical Analysis for Genetic Epidemiology (SAGE version 5.3.1). The results showed that the distribution of EC in families did not fit well into a binomial distribution. The heritability of EC among first-degree and second-degree relatives was $67.0{\pm}7.31%$ and $43.1%{\pm}9.80%$, respectively, and the summing up powered heritability was $53.2{\pm}6.74%$. The segregation ratio was 0.045. Complex segregation analysis showed that the genetic model of EC was additive. The current results provide evidence for an inherited propensity to EC in certain high-risk groups in China, and support efforts to identify the genes that confer susceptibility to this disease.

• Asian Pacific Journal of Cancer Prevention
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• 제15권19호
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• pp.8499-8502
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• 2014

The incidence rate of breast cancer in developed countries is almost three-fold higher than in developing countries. Iran has had one of the lowest incidence rates for breast cancer in the world, but during the recent decades a marked increase has been seen. The purpose of this study was to investigate some established risk factors of breast cancer in Iranian women. A study of 11,850 women participating in abreast screening program was conducted. The 197 women diagnosed with breast cancer and 11,653 healthy women were compared. Logistic regression was performed to investigate associations of reproductive and anthropometric factors with breast cancer risk. Family history of breast cancer (OR=1.94, 95%CI=1.35-2.78), occupation (OR= 1.65,95%CI=1.20-2.25), education level (OR=0.50,95%CI=0.28-0.91), parity (OR=0.27, 95%CI=0.12-0.59), menopausal status (OR=3.15, 95%CI=2.35-4.21), age at menarche (OR=0.33, 95%CI=0.15-0.70), and age at the first pregnancy (OR=4.10, 95%CI=1.13-14.77) were related to the risk of breast cancer. Decrease in parity may to some extent explain the rising trend of incidence of breast cancer incidence in Iranian women.

• Asian Pacific Journal of Cancer Prevention
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• 제16권14호
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• pp.5859-5861
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• 2015

Background: Kidney cancer has shown an increasing trend in recent decades. This study aimed to determine change in the incidence rate between 2003 and 2009 in Iran. Materials and Methods: In this study, national cancer registry data were used. Crude incidence rates were calculated per 100,000 and age-standardized incidence rates (ASRs) were computed using the direct standardization method and the world standard population. Significant trend of incidence rates was examined by the Cochran-Armitage test for linear trend. Results: A total of 6,944 cases of kidney cancer were reported. The incidence cases increased from 595 patients in 2003 to 1,387 patients in 2009. Sex ratio (male to female) was 1.67. ASR also increased from 1.18 in 2003 to 2.52 in 2009 per 100,000, but the increasing trend was not significant. Conclusions: A slow increasing trend of incidence rate was observed in the study population. This may be due to an increase of risk factors. It is suggested to perform a study on risk factors for the cancer.

• Asian Pacific Journal of Cancer Prevention
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• 제15권19호
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• pp.8245-8250
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• 2014

Previous studies investigating the association between 5,10-methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms and colon cancer risk have generated conflicting results. The aim of our meta-analysis was to clarify the precise association. A systematic literature search was conducted to identify all relevant studies. Pooled odds ratio (ORs) with 95% confidence interval (CI) were used to estimate the strength of the association. In this meta-analysis, a total of 13 articles, involving 5,386 cases and 8,017 controls met the inclusion criteria. Overall, a significant association was found between colon cancer risk and the MTHFR C667 polymorphism (TT vs CC+CT: OR=0.79; 95%CI=0.65-0.96; p=0.017). Stratification by ethnicity revealed that MTHFRC667 was associated with colon cancer risk in the non-Asian group (TT vs CC+CT:OR=0.77, 95%CI=0.68-0.89, p=0.000; TT vs CC: OR=0.84, 95%CI=0.73-0.97, p=0.016). Stratification by source of control indicated that MTHFR C667 also correlated with colon cancer risk in the population-based subgroup (TT vs CC: OR=0.85, 95%CI=0.74-0.97, p=0.017; TT vs CC+CT: OR=0.78, 95%CI=0.68-0.89, p=0.000) and hospital-based subgroup (TT vs CC+CT: OR=0.65, 95%CI=0.49-0.86, p=0.003). However, risk was significantly increased for MTHFR A1298C polymorphisms and colon cancer risk in hospital-based studies (C vs A: OR=1.52, 95%CI=1.26-1.83, p=0.000; CC+AC vs AA: OR=1.93, 95%CI=1.47-2.49, p=0.000) but reduced in population-based studies (CC vs AA: OR=0.83, 95%CI=0.70-0.99, p=0.042). In conclusion, the results of our meta-analysis suggest that the MTHFR C667 polymorphism is associated with reduced colon cancer risk, especially for non-Asian populations.

• Journal of Preventive Medicine and Public Health
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• 제36권1호
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• pp.39-46
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• 2003

Objectives : To investigate the availability and demand for overall cancer-related information, and to establish a basic plan for the construction of a cancer database and information system based on the research results from Korea. Methods : Postal and telephone surveys were carried out, between August 2001 and November 2001, of 323 affiliated faculty professors from medical universities and colleges in Korea. The data were analyzed with descriptive statistical methods, with regard to the present status and demand for health and cancer-related information. Results : Most (over 80%) subjects studied utilized the health-related information provided on Internet website from foreign countries, such as Medline, but similar comprehensive information system lacked in Korea. The construction of a cancer-related database of domestic research results was revealed to be in a great demand. Information on registration and statistics (52.8%), study results (48.5%) and study resources (37.4%) were the major ingredients required in the database. In constructing a database of the cancer-related research results, a full-text service, continuous updating of data, and the development of standardized user-friendly searching tool were regarded as the necessary components. The formulation of an information sharing system, regarding cancer-related clinical trials, was investigated as being quite feasible. Conclusion : This study demonstrated the great importance of cancer information systems, and much demand for an available cancer-related database based on Korean research results.

• Asian Pacific Journal of Cancer Prevention
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• 제16권4호
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• pp.1371-1374
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• 2015

Background: Tongue cancer is one of the leading sites of cancer in our population. Aim: To evaluate the socio-demographic profiles and stages at diagnosis of oral tongue (OT) and base of tongue (BT) cancers, and identify any possible variations in characteristics. Materials and Methods: A retrospective analysis was conducted on tongue cancer cases, divided into OT and BT, registered at the hospital cancer registry of North-East India during January 2010 to May 2013. Cases were analyzed for age, gender, residential status and different levels of education for patients, the stage at diagnosis and presence of distant metastasis. Results: A total of 1,113 cases of tongue cancers were registered, 846(76.1%) of BT and 267(23.9%) of OT. While 33.9% of BT cancer patients were above 65 years of age, the figure for OT cancers was 18.4%, stages III and IV accounting for 90.8% and 77%, respectively. The relative risk for distant metastasis in OT cancers was 3.3 (95% CI 1.08-10.1, p=0.03). Conclusions: In the subsites of tongue cancers in our population, the majority arose from the base of tongue, these tending to occur in older individuals and presenting at late stage.

• Asian Pacific Journal of Cancer Prevention
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• 제15권9호
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• pp.4109-4115
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• 2014

Background: Accurate assessment of disease progression requires proper understanding of natural disease process which is often hidden and unobservable. For this purpose, disease status should be clearly detected. But in most diseases it is not possible to detect such status. This study, therefore, aims to present a model which both investigates the unobservable disease process and considers the error probability in diagnosis of disease states. Materials and Methods: Data from 330 patients with gastric cancer undergoing surgery at the Iran Cancer Institute from 1995 to 1999 were analyzed. Moreover, to estimate and assess the effect of demographic, diagnostic and clinical factors as well as medical and post-surgical variables on transition rates and the probability of misdiagnosis of relapse, a hidden Markov multi-state model was employed. Results: Classification errors of patients in alive state without a relapse ($e_{21}$) and with a relapse ($e_{12}$) were 0.22 (95% CI: 0.04-0.63) and 0.02 (95% CI: 0.00-0.09), respectively. Only variables of age and number of renewed treatments affected misdiagnosis of relapse. In addition, patient age and distant metastasis were among factors affecting the occurrence of relapse (state1${\rightarrow}$state2) while the number of renewed treatments and the type and extent of surgery had a significant effect on death hazard without relapse (state2${\rightarrow}$state3)and death hazard with relapse (state2${\rightarrow}$state3). Conclusions: A hidden Markov multi-state model provides the possibility of estimating classification error between different states of disease. Moreover, based on this model, factors affecting the probability of this error can be identified and researchers can be helped with understanding the mechanisms of classification error.

• Asian Pacific Journal of Cancer Prevention
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• 제14권1호
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• pp.523-528
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• 2013

Background: The possibility that electromagnetic fields (EMF) exposure may increase male breast cancer risk has been discussed for a long time. However, arguments have been presented that studies limited by poor quality could have led to statistically significant results by chance or bias. Moreover, data fo the last 10 years have not been systematically summarized. Methods and Results: To confirm any possible association, a meta-analysis was performed by a systematic search strategy. Totals of 7 case-control and 11 cohort studies was identified and pooled ORs with 95% CIs were used as the principal outcome measures. Data from these studies were extracted with a standard meta-analysis procedure and grouped in relation to study design, cut-off point, exposure assessment method, adjustment and exposure model. A statistical significant increased risk of male breast cancer with EMF exposure was defined (pooled ORs = 1.32, 95% CI = 1.14-1.52, P < 0.001), and subgroup analyses also showed similar results. Conclusions: This meta-analysis suggests that EMF exposure may be associated with the increase risk of male breast cancer despite the arguments raised.

• Asian Pacific Journal of Cancer Prevention
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• 제15권3호
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• pp.1205-1210
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• 2014

Background: Previous studies on the association of oral contraceptives (OC) use and lung cancer generated inconsistent findings. The aim of this study was to confirm any definite correlation between OC use and lung cancer risk. Methods: Publications were reviewed and obtained through PubMed and EMBASE databases literature search up to November, 2013. Reference lists from retrieved articles were also reviewed. The language of publication was restricted to English. A meta-analysis was performed to evaluate the association by calculating pooled odds ratios (ORs) and 95% confidence intervals (CIs). Results: A total of 14 studies consisting of 9 case-control studies and 5 cohort studies were finally included in this meta-analysis. There was no significant association observed between OC use and lung cancer risk in the overall analysis (OR=0.91; 95% CI=0.81-1.03). There was a significant protective effect in Europe (OR=0.74; 95% CI=0.60-0.91) and a borderline significant protective effect with an adenocarcinoma histology (OR=0.90; 95% CI=0.80-1.01) in subgroup analyses. No association was observed for methodological quality of study, study design, smoking status and case number of study. Conclusion: This meta-analysis suggests that OC use is not likely to be associated with the risk of lung cancer at all. While a significant protective effect of OC use on lung cancer was observed in Europe, interpretation should be cautious because of the potential biases of low-quality studies. At the same time, more attention should be paid to the possible association of OC use with adenocarcinoma of lung. Our findings require further research, with well-conducted and large-scale epidemiological studies to confirm effects of OC use on lung cancer.

• Asian Pacific Journal of Cancer Prevention
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• 제16권14호
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• pp.5853-5858
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• 2015

Background: The survival rate reflecting prognosis of breast cancer patients is usually estimated based on crude survival methods such as observed and cause-specific. In situations where data are based on population-cancer registries, this method may produce biased estimations. This study therefore aimed to estimate the net survival of breast cancer based on relative survival. Materials and Methods: Data for 622 breast cancer patients diagnosed at the Iran Cancer Institute during 1990-95 and tracked till the end of 2000 were analyzed. For estimation of relative survival, Ederer's second method and SAS (9.1) and STATA (11) software were used. Results: Threeyear relative survivals of 85%, 90%, 80% and 67% were observed for age groups 15-44, 55-59, 60-74, and 75+years-old, respectively. A relative survival of approximately one was observed for two subsequent years for age-group 45-59 years-old. A value greater than one for two subsequent years of follow-up was observed in the age-group 60-74 years-old. Conclusions: Tracking the diagnosis of breast cancer, the relative survival decreases as we go to higher age-groups. It is also perceived that through follow-up, relative survival first decreased and then increased a little. The statistical cure point is acceptable for age group 45-59 years-old while for age-groups 15-44 and 60-74 years old is a sign of low quality data for some follow-up intervals.