• Asian Pacific Journal of Cancer Prevention
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• v.15 no.14
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• pp.5861-5865
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• 2014

High risk forms of the human papilloma virus (HPV) are generally accepted as necessary causative agents for cervical cancer. Recently, a possible relation between HPV and oral squamous cell carcinoma (OSCC) has also been noticed. The present study was conducted to investigate the prevalence of HPV infection in OSCCs in Wuhan city. DNA samples were collected from fresh tissues in 200 patients with OSCC and 68 normal controls. The polymerase chain reaction and direct sequencing were used to identify the HPV types in the samples. The prevalence of HPV of all types in the OSCC group was higher than in the control group (55/200 vs 2/68, OR=11.5, 95% CI=2.6-50.2). HPV16 and HPV18 were the main types detected, with HPV6 was the only low-risk type identified. High-risk HPV types HPV16 and HPV18 are prevalent in OSCC patients and may participate in the development of OSCC with traditional risk factors, tobacco and alcohol, possibly exerting synergistic effects. The results of multinomial logistic regression showed that those who smoked, consumed alcohol and with HPV infection have the highest risk of developing oral cancer (OR=13.3, 95% CI=3.1-56.8). Adjusted for age, smoking and alcohol use, HPV infection was independently associated with oral squamous cell carcinoma.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.9
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• pp.4965-4972
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• 2013

This study aimed to discuss the consumption of alcohol as a risk factor for major cancers. We performed a search in the PubMed database, using the following inclusion criteria: meta-analysis published in English in the last 10 years that addressed the relationship between alcohol and the risk of developing cancer. The results indicate that moderate to heavy consumption of alcohol increases the risk of developing cancer of the oral cavity and pharynx, esophagus, stomach, larynx, colorectum, central nervous system, pancreas, breast and prostate. This review did not find any association between alcohol consumption and an increased risk of cancers of the lung, bladder, endometrium and ovary. It was also observed that alcohol consumption may be inversely related to thyroid cancer. Our systematic review has confirmed consumption of alcohol as a risk factor for the development of several types of cancer.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.28 no.5
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• pp.364-371
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• 2002

Many chemical compopunds are converted into reactive electrophilic metabolites by the oxidative(Phase I) enzymes, which are mainly cytochrome P-450 enzyme(CYPs). Phase II conjugating enzymes, such as glutathione S-transferase(GST), usually act as inactivation of enzymes. Genetic polymorphisms have been found to be associated with increased susceptibility to cancer of the lung, bladder, breast and colorectal. Many of the polymorphic genes of carcinogen metabolism show considerably different type of cancer among different ethnic groups as well as individuals within the same group. The aim of this study is (1) to establish the frequencies of genetic polymorphisms of GSTM1 and CYP1A1 in Korean oral squamous cell carcinoma(SCC), (2) to associate oral SCC with the risk of these genetic polymorphisms. The genetic polymorphisms of the GSTM1 and the CYP1A1 genes among 50 Korean oral SCC were analyzed using polymerase chain reaction(PCR). The results suggest that the homozygote and the mutant type of CYP1A1 MspI polymorphisms may be associated with genetic susceptibility to oral SCC in Korean. A combination of the GSTM1 null type with the homozygote(m1/m1), and the mutant(m2/m2) type of CYP1A1 MspI polymorphisms showed a relatively high risk of oral SCC in Korean. In the smoking group, the GSTM1 wild genotype may be the high risk factor of oral SCC in Korean. These data coincide with the hypothesis which states that different susceptibility to cancer of genetic polymorphisms exist among different ethnic group and different types of human cancer.

• The Korean Journal of Health Service Management
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• v.8 no.4
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• pp.221-229
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• 2014

Breast cancer is increasing at a remarkable rate in Korea. We investigated the association between oral contraceptive use and breast cancer in Korean women. Using the 5th Korea National Health and Nutrition Examination Survey data, 8,495 women aged over 30 years are analyzed. Furthermore, the data used in this study is obtained using a complex sampling method in order that it is generalized. The previous studies in Korea, were not statistically significant due to the relatively short duration during which oral contraceptives had been available. However, the longer duration of oral contraceptive use exhibits tendency to increase the risk of breast cancer. Women using oral contraceptives, particularly for more than two years have an increased occurrence of breast cancer compared with women who do not use oral contraceptives. This result reflects the late introduction of oral contraceptives in Korea compared with developed countries. The recent increase in interest about the use of oral contraceptives has been increasing for a variety of reasons. Therefore, it is necessary for continuous and specific clinical studies to examine the connections between the first use of oral contraceptives, oral contraceptives use duration, adverse effects of oral contraceptives and breast cancer in order to develop strategies for preventing breast cancer.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.3
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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.

• Korean Journal of Community Nutrition
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• v.13 no.4
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• pp.573-581
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• 2008

Although it is well known that cancer patients suffer from malnutrition, there are few published studies on malnutrition in outpatients receiving chemotherapy in Korea. This study aimed to evaluate nutritional risk in oncology outpatients receiving chemotherapy and to show the baseline data to set up nutritional management programs for cancer patients. This is a retrospective observational analysis on 1,962 patients referred for nutritional education before or during chemotherapy at Seoul National University Hospital Cancer Center from January 2006 to May 2007. According to a malnutrition screening tool, the proportion of patients having malnutrition risk was 23.0%. In the case of upper gastrointestinal cancer, more than 50% of patients were assessed as being at the risk of malnutrition. They showed more than 7% weight loss compared to their usual body weight and poor oral intake; energy intake was less than 100% of Basal Energy Expenditure(BEE) and protein intake was less than or equal to 0.77 g/kg/d. However, only 6.3% of breast cancer patients had risk of malnutrition and their oral intake was better; energy intake was 121% of BEE, and protein intake was 0.90 g/kg/d. Outpatients receiving chemotherapy had different nutritional risk depending on their cancer site. Nutritional management program should be conducted differently, depending on the cancer site and upper gastrointestinal cancer patients at high risk of malnutrition should basically have nutritional assessment and intervention.

• Toxicological Research
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• v.8 no.2
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• pp.317-329
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• 1992

Fifty chemicals are currently classified as human carcinogens based on epidemiologic and animal data. Humans are daily exposed to them from various sources of exposure via inhalation, dermal contact and oral ingestion. To reduce cancer risk to man, these human carcinogens should be appropriately regulated and monitored environmentally or biologically for routine human cancer risk assessment. A number of mathematical risk assessment models have been introduced, but any realistic and relevant model system is not available for humans. A mechanistic process for human cancer risk assessment was comprehensively reviewed and problems were also discussed. Here, a new conceptual approach using epidemiology and biological human monitoring was suggested for the most relevant method to study human cancer risk assessment.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.15
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• pp.6193-6200
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• 2015

Head and neck cancer, including oral cancer, is the sixth most common cancer in humans worldwide. More than 90% of oral cancers are of squamous cell carcinoma type. Recent studies have shown a strong relationship between human papillomavirus (HPV) infection and head and neck cancer, especially oropharyngeal squamous cell carcinoma (OPSCC) and oral squamous cell carcinoma (OSCC). Moreover, the incidence of HPV-related OSCC appears to be on the rise while HPV-unrelated OSCC tends to have stabilized in the past decades. p16, a tumor suppressor gene, normally functions as a regulator of the cell cycle. Upon infection with high-risk types of HPV (HR-HPV), particularly types 16, 18, 31, 33, 34, 35, 39, 51, 52, 56, 58, 59, 66, 68, and 70, the expression of p16 is aberrantly overexpressed. Therefore, the expression of p16 is widely used as a surrogate marker for HPV infection in head and neck cancer.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.19
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• pp.8351-8359
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• 2014

Background: Recent epidemiological data have implicated human papilloma virus (HPV) infection in the pathogenesis of head and neck cancers, especially oropharyngeal cancers. Although, HPV has been detected in varied amounts in persons with oral dysplasia, leukoplakias and malignancies, its involvement in oral tongue carcinogenesis remains ambiguous. Materials and Methods: HPV DNA prevalence was assessed by PCR with formalin fixed paraffin embedded sections (n=167) of oral tongue squamous cell carcinoma patients and the physical status of the HPV16 DNA was assessed by qPCR. Immunohistochemistry was conducted for p16 evaluation. Results: We found the HPV prevalence in tongue cancers to be 51.2%, HPV 16 being present in 85.2% of the positive cases. A notable finding was a very poor concordance between HPV 16 DNA and p16 IHC findings (kappa<0.2). Further molecular classification of patients based on HPV16 DNA prevalence and p16 overexpression showed that patients with tumours showing p16 overexpression had increased hazard of death (HR=2.395; p=0.005) and disease recurrence (HR=2.581; p=0.002) irrespective of their HPV 16 DNA status. Conclusions: Our study has brought out several key facets which can potentially redefine our understanding of tongue cancer tumorigenesis. It has emphatically shown p16 overexpression to be a single important prognostic variable in defining a high risk group and depicting a poorer prognosis, thus highlighting the need for its routine assessment in tongue cancers. Another significant finding was a very poor concordance between p16 expression and HPV infection suggesting that p16 expression should possibly not be used as a surrogate marker for HPV infection in tongue cancers. Interestingly, the prognostic significance of p16 overexpression is different from that reported in oropharyngeal cancers. The mechanism of HPV independent p16 over expression in oral tongue cancers is possibly a distinct entity and needs to be further studied.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.4
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• pp.1659-1665
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• 2014

The present study conducted with 100 oral cancer patients at a private tertiary care hospital in Delhidemonstrated that stage III cancer was associated with longer use of tobacco and poor oral hygiene. There was also statistically significant association (p<.05) between consumption of tobacco and alcohol. More than 60% treatment expenditure was on surgery followed by accommodation (9%) and investigations (8%). The effect of tobacco was well known among patients as 76% of the patients knew that common cancer in tobacco chewer is 'oral cancer', 22% of the patients however responded that they did not know which cancer is common in tobacco chewers. 58% said that they learnt about ill effects of tobacco from media while 24% said they learnt from family and friends. Out of 78 tobacco users, 60 (77%) said that they never received help to quit tobacco while 18(23%) have received help to quit.