High Risk Of Nasopharyngeal Carcinoma Research Articles

The human oral - nasopharynx microbiome as a risk screening tool for nasopharyngeal carcinoma.

Nasopharyngeal carcinoma (NPC) is a common head and neck cancer with a poor prognosis. There is an urgent need to develop a simple and convenient screening tool for early detection and risk screening of NPC. 139 microbial samples were collected from 40 healthy people and 39 patients with nasopharyngeal biopsy. A total of 40 and 39 oral, eight and 27 nasal cavity, nine and 16 nasopharyngeal microbial samples were collected from the two sets of individuals. A risk screening tool for NPC was established by 16S rDNA sequencing and random forest. Patients with nasopharyngeal biopsy had significantly lower nasal cavity and nasopharynx microbial diversities than healthy people. The beta diversity of the oral microbiome was significantly different between the two groups. The NPC screening tools based on nasopharyngeal and oral microbiomes have 88% and 77.2% accuracies, respectively. The nasopharyngeal biopsy patients had significantly higher Granulicatella abundance in their oral cavity and lower Pseudomonas and Acinetobacter in the nasopharynx than healthy people. This study established microbiome-based non-invasive, simple, no radiation, and low-cost NPC screening tools. Individuals at a high risk of NPC should be advised to seek further examination, which might improve the early detection of NPC and save public health costs.

Epstein-Barr virus-based nasopharyngeal carcinoma population screening

: Nasopharyngeal carcinoma (NPC) is characterized by its distinct geographical distribution and has a high incidence in southern China and Southeast Asia. Early diagnosis and treatment are the best strategies for individuals identified to have a high risk of NPC. The identification of high-risk populations and the use of appropriate screening methods are key factors when screening for NPC. Despite the discovery of the close association of Epstein-Barr virus (EBV) with NPC, the exact role of the virus in the development of NPC has not been completely elucidated. EBV serological antibody testing is of great significance while screening for NPC, and plasma EBV-DNA has been used for population screening. The screening also includes clinical examination (lymphatic palpation and indirect examination of the nasopharynx using a mirror) and obtaining the family history of patients with NPC. The main secondary screening methods include nasopharyngeal fiberscopy. Another approach to diagnose NPC includes cytological examination of the nasopharyngeal brush exfoliates. Evidence suggests that serological screening for NPC can increase the rate of early diagnosis and significantly improve the 5-year survival rate of the affected population. However, the NPC serological screening protocol has some shortcomings. For example, the positive predictive value needs to be improved. Further research into NPC should be focused on methods that will accurately identify high-risk individuals and optimize screening. Here, we have reviewed the latest progress in EBV-based NPC population screening.

A comprehensive risk score for effective risk stratification and screening of nasopharyngeal carcinoma

Using Epstein-Barr virus (EBV)-based markers to screen populations at high risk for nasopharyngeal carcinoma (NPC) is an attractive preventive approach. Here, we develop a comprehensive risk score (CRS) that combines risk effects of EBV and human genetics for NPC risk stratification and validate this CRS within an independent, population-based dataset. Comparing the top decile with the bottom quintile of CRSs, the odds ratio of developing NPC is 21 (95% confidence interval: 12–37) in the validation dataset. When combining the top quintile of CRS with EBV serology tests currently used for NPC screening in southern China, the positive prediction value of screening increases from 4.70% (serology test alone) to 43.24% (CRS plus serology test). By identifying individuals at a monogenic level of NPC risk, this CRS approach provides opportunities for personalized risk prediction and population screening in endemic areas for the early diagnosis and secondary prevention of NPC.

A combination of two ELISA tests for nasopharyngeal carcinoma screening in endemic areas based on a case-control study.

For populations with a high risk of nasopharyngeal carcinoma (NPC) in Guangdong province in southern China, mass screening is the first choice to prevent death from NPC. To improve the performance of NPC screening, we used a combination based on the IgA antibody against the Epstein-Barr virus (EBV) capsid antigen (VCA-IgA) and the IgA antibody against Epstein-Barr virus nuclear antigen 1 (EBNA1-IgA) to NPC screening by enzyme-linked immunosorbent assay (ELISA). A multiplication model was applied to measure the level of the combination. We evaluated the NPC screening effect of the markers.A case-control study was performed to assess the NPC screening effect of the markers. A total of 10,894 serum specimens were collected, including 554 samples from NPC patients and 10,340 samples from healthy controls. In the training stage, 640 subjects were randomly selected, including 320 NPC cases and 320 healthy controls. In the verification stage, 10,254 subjects were used to verify the NPC screening effect of the combination. Receiver operating characteristic (ROC) analysis was performed. In the verification stage, the combination achieved an sensitivity of 91.45%, a specificity of 93.45%, and an area under the ROC curve (AUC) of 0.978 (95% CI [0.968–0.987]). Compared with VCA-IgA and EBNA1-IgA individually, the combination had an improved screening performance. A probability (PROB) calculated by logistic regression model based on VCA-IgA and EBNA1-IgA was applied to NPC screening by ELISA in China. The AUC of the combination was a little bit larger than the PROB. There was a slight increase (3.13%) in the sensitivity of the combination compared to the sensitivity of the PROB, while the specificity was lower for the combination (92.50%) than for the PROB (95.94%). We successfully applied a combination of two ELISA tests based on VCA-IgA and EBNA1-IgA for NPC screening by using a multiplication model. The results suggested that the combination was effective and can be an option for NPC screening.

Genome sequencing analysis identifies Epstein-Barr virus subtypes associated with high risk of nasopharyngeal carcinoma.

Epstein-Barr virus (EBV) infection is ubiquitous worldwide and is associated with multiple cancers, including nasopharyngeal carcinoma (NPC). The importance of EBV viral genomic variation in NPC development and its striking epidemic in southern China has been poorly explored. Through large-scale genome sequencing of 270 EBV isolates and two-stage association study of EBV isolates from China, we identified two non-synonymous EBV variants within BALF2 strongly associated with the risk of NPC (odds ratio (OR) = 8.69, P=9.69×10−25 for SNP 162476_C; OR = 6.14, P=2.40×10−32 for SNP 163364_T). The cumulative effects of these variants contributed to 83% of the overall risk of NPC in southern China. Phylogenetic analysis of the risk variants revealed a unique origin in Asia, followed by clonal expansion in NPC-endemic regions. Our results provide novel insights into NPC endemic in southern China and also enable the identification of high-risk individuals for NPC prevention.

Cost-effectiveness of Screening for Nasopharyngeal Carcinoma among Asian American Men in the United States.

Most patients with nasopharyngeal carcinoma (NPC) in the United States are diagnosed with stage III-IV disease. Screening for NPC in endemic areas results in earlier detection and improved outcomes. We examined the cost-effectiveness of screening for NPC with plasma Epstein-Barr virus DNA among Asian American men in the United States. We used a Markov cohort model to estimate discounted life-years, quality-adjusted life-years (QALYs), costs, and incremental cost-effectiveness ratios for screening as compared with usual care without screening. The base case analysis considered onetime screening for 50-year-old Asian American men. Confirmatory testing was magnetic resonance imaging and nasopharyngoscopy. Cancer-specific outcomes, health utility values, and costs were determined from cancer registries and the published literature. For Asian American men, usual care without screening resulted in the detection of NPC at stages I, II, III-IVB, and IVC among 6%, 29%, 54%, and 11% of those with cancer, respectively, whereas screening resulted in earlier detection with a stage distribution of 43%, 24%, 32%, and 1%. This corresponded to an additional 0.00055 QALYs gained at a cost of $63 per person: an incremental cost of $113,341 per QALY gained. In probabilistic sensitivity analysis, screening Asian American men was cost-effective at $100,000 per QALY gained in 35% of samples. Although screening for NPC with plasma Epstein-Barr virus DNA for 50-year-old Asian American men may result in earlier detection, in this study it was unlikely to be cost-effective. Screening may be reasonable for certain subpopulations at higher risk for NPC, but clinical studies are necessary before implementation.

Lack of association between cigarette smoking and Epstein Barr virus reactivation in the nasopharynx in people with elevated EBV IgA antibody titres

BackgroundSubjects with elevated Epstein-Barr virus (EBV) immunoglobulin A (IgA) titers have a higher risk of developing nasopharyngeal carcinoma (NPC), indicating that reactivation of EBV in the local mucosa might be important for NPC carcinogenesis. Cigarette smoking appears to be one of the environmental risk factors for NPC. However, it remains unclear whether smoking-induced nasopharyngeal carcinogenesis acts through reactivating EBV in the nasopharyngeal mucosa. Therefore, this study aims to investigate the association between cigarette smoking and nasopharyngeal EBV reactivation in a NPC high-risk population.MethodsA NPC high-risk cohort study, established from a population-based NPC screening program of 22,816 subjects, consisted of 1045 subjects with elevated serum IgA antibodies against EBV viral capsid antigen (VCA/IgA). Among high-risk subjects, information on detailed cigarette smoking history was collected among 313 male subjects. The associations between cigarette smoking and EBV antibody levels, EBV DNA load of the nasopharynx were analyzed.ResultsNo significant association was observed between either nasopharyngeal EBV DNA load or serum VCA/IgA titers and smoking status, age at smoking initiation, daily smoking intensity, smoking duration, cigarette type, or pack-years of smoking. Cigarette smoking characteristics in all subgroups did not correlate with nasopharyngeal EBV DNA positivity or EBV VCA/IgA seropositivity.ConclusionsIn a population at high risk of NPC, our study suggests that cigarette smoking is neither associated with nasopharyngeal EBV DNA load nor serum VCA/IgA antibody level. Smoking-associated NPC carcinogenesis may act through other mechanisms than reactivating nasopharyngeal EBV replication.

Biyuanling suppresses the toluene-2, 4-diisocyanate induced allergic rhinitis in guinea pigs.

Allergic rhinitis (AR), one of the common diseases of the upper respiratory system, is associated with high risk of nasopharyngeal carcinoma. Biyuanling Granules (BLG), a formulated preparation of traditional Chinese medicine, has been used in China for treatment of AR for more than a decade; however, its exact action against allergic rhinitis and the mechanism involved remain unclear. In this study, we studied the effects of BLG on allergic rhinitis induced by toluene-2, 4- diisocyanate (TDI) in guinea pigs. The anti-AR effects of BLG were evaluated by behavior observations, histological examinations of the nasal tissues stained with hematoxylin and eosin staining (H&E), immunohistochemical analyses of pulmonary surfactant associated protein (SP), Bcl-2 Associated X Protei (Bax), tumor necrosis factor (TNF-α) and vascular cell adhesion molecule-1 (VCAM-1) in the nasal mucosa, and serum tests of interleukin-4 (IL-4) and human SARS-specific immunoglobulin (SIgE) levels. We observed that in the AR-positive animals treated with BLG, the symptom scores were significantly higher (P < 0.01), the nasal mucosa edemas and inflammatory infiltrates were significantly alleviated (P < 0.01) and the serum IL-4 and SIgE levels were significantly decreased (P < 0.05) as compared with the control group. Immunohistochemical examinations of the nasal mucosa demonstrated that the expressions of TNF-α, SP and VCAM-1 were significantly decreased (P < 0.01), whereas Bax expression was increased in the BLG treatment groups (P < 0.05). These results indicate that BLG can effectively suppress the TDI-induced AR, and that the protective effects of BLG were associated with reductions of TNF-α, SP and VCAM-1, and an elevation of Bax, suggesting that BLG exerts its AR-suppressive effects through inhibition of inflammatory response.

The value of plasma EBV-DNA testing in high-risk group of nasopharyngeal carcinoma in the nasal endoscopy

Objective:The aim of this study is to evaluate the level of plasma EBV DNA and nasal endoscopy in high risk population of nasopharyngeal carcinoma, and to explore the value of EBV DNA testing in nasal endoscopy. Method:The nasopharyngeal carcinoma was screened in High-incidence Area of Zhongshan City. EBV antibody was detected by ELISA, and 427 patients with high risk of nasopharyngeal carcinoma were identified. In the high risk population the plasma EBV-DNA was measured using Fluorescent quantitative PCR, and all patients were used nasal endoscopy in the first two years. The application value of EBV DNA and nasopharyngeal endoscopic biopsy were analyzed. Result:There were 427 NPC high risk population in first screening. The rates of nasopharyngeal biopsy in EBV DNA positive and EBV DNA negative population were 90.2% (55/61) and 13.9% (51/366), respectively. The rate of NPC nasopharyngeal biopsy in EBV DNA positive population was higher than that in EBV DNA negative population (P<0.01). The rate of NPC detection in EBV DNA positive group (60.7%) was higher than that (3.3%) in EBV DNA negative population (P<0.01). In first year follow up, there were 286 NPC high risk population. The rates of nasopharyngeal biopsy in EBV DNA positive and EBV DNA negative population were 91.2% (31/34) and 11.9% (30/252), respectively. The rate of NPC nasopharyngeal biopsy in EBV DNA positive population was higher than that in EBV DNA negative population (P<0.01). The rate of NPC detection in EBV DNA positive group (17.6%) was higher than that (1.6%) in EBV DNA negative population (P<0.01). The positive predicative value of serological risk assessment was 8.3% (59/713), but for NPC high risk group, adding quantitative analysis of plasma EBV DNA, the positive predicative value was 45.3% (43/95). The early diagnosis rates in EBV DNA positive and EBV DNA negative population were 79.1% (34/43) and 93.8% (15/16), respectively. There was no significant difference in early diagnosis rates in two groups (P>0.05). Conclusion:The positive rate of plasma EBV DNA in high risk group of nasopharyngeal carcinoma may be helpful for nasal endoscopic nasopharyngeal biopsy, which can greatly improve the positive predictive value of high risk population of nasopharyngeal carcinoma. For NPC high risk population, Therefore, EBV DNA positive population are the focus for NPC screening.

HLA-A*26-A*30 and HLA-DRB1*10 could be predictors of nasopharyngeal carcinoma risk in high-risk Tunisian families.

We investigated human leukocyte antigen (HLA) profiles for Tunisians with nasopharyngeal carcinoma (NPC), their families, and a sample of unrelated healthy Tunisians in order to identify HLA specificities associated with familial NPC. HLA-A, -B, and -DRB1 typing was successful for 36 NPC patients, 72 unaffected family members, and 130 community controls, and the chi square or Fisher exact test was used to compare allele frequencies between cases and controls. We observed a consistent protective effect of HLA-DRB1*10 on NPC development. However, none of the NPC patients or their family members had a positive result for this HLA marker (0% vs 9.2% in controls, P = 0.047). In addition, HLA-A*26 was probably an induction marker, as its allelic frequency was significantly higher among NPC patients than among controls (P = 0.003) and among NPC patients than among at-risk family members (P = 0.067). Logistic regression analysis of the joint effect of selected HLA specificities showed that HLA-A*26 and HLA-A*30 were co-associated and have an important effect on NPC risk. Despite the small size of our cohort, we showed that HLA-A*26-A*30 and HLA-DRB1*10 might be predictive markers for NPC screening of Tunisian families with a high risk of NPC.

Association of Single-Nucleotide Polymorphisms in DC-SIGN with Nasopharyngeal Carcinoma Susceptibility.

The aim of this study was to explore potential relationships of four single-nucleotide polymorphisms (SNPs) in the gene encoding dendritic cell-specific intercellular adhesion molecule 3-grabbing nonintegrin (DC-SIGN) with risk of nasopharyngeal carcinoma (NPC). The DC-SIGN SNPs rs7252229, rs4804803, rs2287886, and rs735240 were genotyped in 477 unrelated NPC patients and 561 cancer-free controls. At rs7252229, risk of NPC was significantly lower in individuals with GC (odds ratio [OR] 0.076, 95% confidence interval [CI] 0.008–0.690), GG (OR 0.056, 95%CI 0.006–0.487), or GC + GG (OR 0.059, 95%CI 0.007–0.515) than in individuals with the CC genotype, after adjusting for age, gender, smoking history, and EBV-VCA-IgA status. At rs4804803, risk of NPC was significantly higher in individuals with the genotype GG than in those with the genotype AA (adjusted OR 9.038, 95%CI 1.708–47.822). At rs735240, risk of NPC did not change significantly with genotypes AG, GG, or AG + GG after adjusting for age, gender, and smoking history. However, when data were also adjusted for EBV-VCA-IgA status, three genotypes emerged as associated with significantly higher risk of NPC than the AA genotype: AG (OR 2.976, 95%CI 1.123–7.888), GG (OR 3.314, 95%CI 1.274–8.622), or GG + AG (OR 3.191, 95%CI 1.237–8.230). Our results suggest that DC-SIGN SNPs rs7252229, rs4804803, and rs735240 may influence NPC risk in the Chinese population. The mechanisms mediating this risk require a further study.

Increased Risk of Nasopharyngeal Carcinoma with Increasing Levels of Diet-Associated Inflammation in an Italian Case–Control Study

ABSTRACTPurpose: Components of diet can modulate inflammation and therefore may have an important role in the development of nasopharyngeal carcinoma (NPC). Little is known about the inflammatory potential of diet in relation to nasopharyngeal carcinogenesis. Methods: Data from an Italian multicenter case–control study conducted between 1992 and 2008 and including 198 cases with incident, histologically confirmed NPC, and 594 controls hospitalized for acute nonneoplastic diseases were used to estimate the relation between a dietary inflammatory index (DII) and the risk of NPC. The DII was computed based on the intake of selected dietary factors assessed by a validated 78-item food frequency questionnaire. Logistic regression models were used to estimate odds ratios (ORs) adjusted for study center, place of living, sex, age, year of interview, education, tobacco smoking, alcohol drinking, and energy intake using the residual method. Results: Subjects with higher DII scores had an increased risk of NPC, with each DII point increasing risk by nearly 20% [OR: 1.19; 95% confidence interval (CI): 1.05–1.36]. Compared to subjects in the lowest DII tertile, those in the highest tertile had >60% higher risk of NPC (OR: 1.64; 95% CI: 1.06–2.55; Ptrend = 0.04). Conclusion: These results indicate that inflammatory potential of diet plays a role in NPC.

Subtype distribution and long-term titer fluctuation patterns of serum anti-Epstein-Barr virus antibodies in a non-nasopharyngeal carcinoma population from an endemic area in South China: a cohort study.

BackgroundSerum immunoglobulin A antibodies against Epstein–Barr virus (EBV), viral capsid antigen (VCA-IgA) and early antigen (EA-IgA), are used to screen for nasopharyngeal carcinoma (NPC) in endemic areas. However, their routine use has been questioned because of a lack of specificity. This study aimed to determine the distributions of different subtypes of antibody and to illustrate how the natural variation patterns affect the specificity of screening in non-NPC participants.MethodsThe distribution of baseline VCA-IgA was analyzed between sexes and across 10-year age groups in 18,286 non-NPC participants using Chi square tests. Fluctuations in the VCA-IgA level were assessed in 1056 non-NPC participants with at least two retests in the first 5-year period (1987–1992) after the initial screening using the Kaplan–Meier method.ResultsThe titers of VCA-IgA increased with age (P < 0.001). Using a previous serological definition of high NPC risk, nasopharyngeal endoscopy and/or nasopharyngeal biopsy would be recommended in 55.5% of the non-NPC participants with an initial VCA-IgA-positive status and in 20.6% with an initial negative status during the 5-year follow-up. However, seroconversions were common; 85.2% of the participants with a VCA-IgA-positive status at baseline converted to negative, and all VCA-IgA-negative participants changed to positive at least once during the 5-year follow-up. The EA-IgA status had a high seroconversion probability (100%) from positive to negative; however, it had a low probability (19.6%) from negative to positive.ConclusionsAge- and sex-specific cutoff titer values for serum anti-EBV antibodies as well as their specific titer fluctuation patterns should be considered when defining high NPC risk criteria for follow-up diagnostics and monitoring.

Association of polymorphisms hOGGI rs1052133 and hMUTYH rs3219472 with risk of nasopharyngeal carcinoma in a Chinese population.

This case–control study investigates the possible relationships between the single-nucleotide polymorphisms rs1052133 in the human 8-oxoguanine DNA glycosylase 1 (hOGG1) gene and rs3219472 in the human MutY glycosylase homologue (hMUTYH) gene and the risk of nasopharyngeal carcinoma (NPC). The two polymorphisms were genotyped in 488 unrelated NPC patients and 573 cancer-free controls. Genotype GG at rs1052133 was associated with significantly lower NPC risk than genotypes GC + CC (odds ratio [OR] 0.770, 95% confidence interval [CI] 0.595–0.996, P=0.012). In subgroup analyses, subjects with genotype GG at rs1052133 were at lower risk of NPC than those with GC or CC among individuals older than 40 years (OR 0.706, 95% CI 0.524–0.950), women (OR 0.571, 95% CI 0.337–0.968), and those with no smoking history (OR 0.634, 95% CI 0.463–0.868). No significant association was seen between polymorphisms at hMUTYH rs3219472 and the risk of NPC. However, gene–gene interaction analysis showed that subjects with genotype CC at rs1052133 and genotype AA at rs3219472 (CC/AA) were at 2.887-fold higher risk of NPC than those with GG/GG, 3.183-fold higher risk than those with GG/GA, and 3.392-fold higher risk than those with GG/AA. Our results suggest that hOGG1 rs1052133 polymorphism may play an important role in NPC pathogenesis, especially among women, >40 years old, and those with no smoking history. The hMUTYH rs3219472 polymorphism may interact with hOGG1 rs1052133 polymorphism to influence susceptibility to NPC.

A single nucleotide polymorphism in the Epstein-Barr virus genome is strongly associated with a high risk of nasopharyngeal carcinoma.

BackgroundEpstein-Barr virus (EBV) commonly infects the general population and has been associated with nasopharyngeal carcinoma (NPC), which has a high incidence in certain regions. This study aimed to address how EBV variations contribute to the risk of NPC.MethodsUsing logistic regression analysis and based on the sequence variations at EBV-encoded RPMS1, a multi-stage association study was conducted to identify EBV variations associated with NPC risk. A protein degradation assay was performed to characterize the functional relevance of the RPMS1 variations.ResultsBased on EBV-encoded RPMS1 variations, a single nucleotide polymorphism (SNP) in the EBV genome (locus 155391: G>A, named G155391A) was associated with NPC in 157 cases and 319 healthy controls from an NPC endemic region in South China [P < 0.001, odds ratio (OR) = 4.47, 95% confidence interval (CI) 2.71–7.37]. The results were further validated in three independent cohorts from the NPC endemic region (P < 0.001, OR = 5.20, 95% CI 3.18–8.50 in 168 cases vs. 241 controls, and P < 0.001, OR = 5.27, 95% CI 4.06–6.85 in 726 cases vs. 880 controls) and a non-endemic region (P < 0.001, OR = 7.52, 95% CI 3.69–15.32 in 58 cases vs. 612 controls). The combined analysis in 1109 cases and 2052 controls revealed that the SNP G155391A was strongly associated with NPC (Pcombined < 0.001, OR = 5.27, 95% CI 4.31–6.44). Moreover, the frequency of the SNP G155391A was associated with NPC incidence but was not associated with the incidences of other EBV-related malignancies. Furthermore, the protein degradation assay showed that this SNP decreased the degradation of the oncogenic RPMS1 protein.ConclusionsOur study identified an EBV variation specifically and significantly associated with a high risk of NPC. These findings provide insights into the pathogenesis of NPC and strategies for prevention.

Smoking and nasopharyngeal carcinoma mortality: a cohort study of 101,823 adults in Guangzhou, China.

BackgroundNasopharyngeal carcinoma (NPC), also known as Cantonese cancer, is rare worldwide, but has particularly high incidence in North Africa and Southeast Asia, especially in Guangdong, China, such as Guangzhou. Tobacco causes head and neck cancers, but nasopharyngeal carcinoma is not included as causally related to smoking in the 2014 United States Surgeon General’s report. Prospective evidence remains limited. We used Guangzhou Occupational Cohort data to conduct the first and robust prospective study on smoking and NPC mortality in an NPC high-risk region.MethodsInformation on demographic characteristics and smoking status was collected through occupational health examinations in factories and driver examination stations from March 1988 to December 1992. Vital status and causes of deaths were retrieved until the end of 1999. Cox proportional hazard model was used to assess the association of smoking with NPC mortality.ResultsOf 101,823 subjects included for the present analysis, 34 NPC deaths occurred during the average 7.3 years of follow up. The mean age (standard deviation) of the subjects was 41 (5.7) years. Compared with never smokers, the hazard ratio (HR) of NPC mortality was 2.95 (95 % confidence interval 1.01–8.68; p = 0.048) for daily smokers and 4.03 (1.29–12.58; p = 0.016) for smokers with more than 10 pack-years of cumulative consumption, after adjusting for age, sex, education, drinking status, occupation and cohort status and accounting for smoking-drinking interaction. The risk of NPC mortality increased significantly with cigarettes per day (p for trend = 0.01) and number of pack-years (p for trend = 0.02).ConclusionsIn this first and largest cohort in a high NPC risk region, smoking was associated with higher NPC mortality. The findings have shown statistically significant dose–response trend between smoking amount and smoking cumulative consumption and the risk of NPC mortality, but due to the small event number, further studies with larger sample size are needed to confirm the findings in the present study. Our results support that smoking is one of the risk factors likely to be causally associated with NPC mortality.Electronic supplementary materialThe online version of this article (doi:10.1186/s12885-015-1902-9) contains supplementary material, which is available to authorized users.

Hepatitis B virus infection and risk of nasopharyngeal carcinoma in southern China.

Whether or not hepatitis B virus (HBV) infection plays a role in the development of nasopharyngeal carcinoma (NPC) is largely unknown. Our study aimed to assess the association between HBV infection and the risk of NPC in Southern China. We conducted a case-control study including 711 NPC cases and two groups of controls. The first control group consisted of 656 individuals with other benign tumors unrelated to HBV infection and the second group consisted of 680 healthy population controls. Multivariable ORs and corresponding 95% confidence intervals (CI) for NPC were estimated by logistic regression. Patients with NPC had higher prevalence of antibodies against hepatitis B core antigen-positive [anti-HBc-(+); 47.26%] compared with either benign tumor controls (39.33%; P < 0.01) or healthy controls (41.18%; P = 0.04). In multivariable models adjusting for a set of risk factors for NPC, anti-HBc-(+) was significantly associated with a higher risk of NPC [adjusted OR (AOR), 1.40; 95% CI, 1.12-1.74 compared with the benign tumor controls and AOR, 1.48; 95% CI, 1.05-2.08 compared with the healthy controls]. The association was not modified by hepatitis B surface antigen (HBsAg) status. Finally, compared with the healthy controls, individuals with both anti-HBc-(+) and EBV antibodies had largely increased risk of NPC (AOR, 141.82; 95% CI, 68.73-292.62). Our study suggests that HBV infection is associated with NPC risk in Southern China. Prevention for HBV infection may play a role in the development of NPC.

Contribution of susceptibility locus at HLA class I region and environmental factors to occurrence of nasopharyngeal cancer in Northeast India.

High incidence of nasopharyngeal carcinoma (NPC) has been reported from China, Southeast Asia and Northeast (NE) region of India. Populations at geographic regions having higher incidence of NPC display human leukocyte antigen (HLA) distribution patterns different from areas having low incidence. The current study has investigated the contribution of environmental risk factors and ethnic variation of microsatellite markers in HLA region for the high incidence of NPC in NE India. Genotyping of HLA region using 33 microsatellite markers by fragment length analysis was done in 220 study subjects (120 NPC patients and 100 healthy controls). Association analysis showed two adjacent microsatellite markers HL003 (allele 121) and D6S2704 (allele 218) in the HLA class I region having association with high risk of NPC while allele 127 of HL003 and allele 255 of D6S2678 conferred a protective effect. The environmental factors mainly use of firewood (odds ratio (OR) = 3.797385, confidence interval (CI) = 1.97-7.30, P < 0), living in mud house (OR = 3.46, CI = 1.19-10.08, P = 0.022) and consumption of alcohol (OR = 2.11, CI = 1.02-4.37, P = 0.043) were found as major risk factors for NPC. Higher-order interaction showed combination of smoked food consumption and firewood use for cooking in multifactor dimensionality reduction (MDR) analysis and interaction of non-firewood users, non-ventilated houses and residence in mud houses in classification and regression tree (CART) analysis as the significant risk factors for NPC. Expression of Epstein-Barr virus (EBV) RNA was found in 92% (23/25) of NPC cases suggesting its significant role in NPC aetiopathogenesis. This study identified association of NPC with a susceptibility locus in the HLA class I region which has complex interaction with viral DNA and environmental factors.

Subsequent risk of nasopharyngeal carcinoma among patients with allergic rhinitis: A nationwide population-based cohort study

The purpose of this study was to examine the risk of nasopharyngeal carcinoma (NPC) after a diagnosis of allergic rhinitis. We identified 67,532 patients with allergic rhinitis (allergic rhinitis cohort) and a 135,064 control cohort with the same mean age and sex ratio by using a Taiwan Longitudinal Health Insurance Database (LHID) sample from 2000 to 2005. After adjusting for the possible confounding factors of the study, the allergic rhinitis cohort had a 2.33-fold higher risk of developing NPC than did the comparison cohort. The frequency of allergic rhinitis visits was correlated with the risk of subsequent NPC. Patients with 4 or more allergic rhinitis visits per year were significantly associated with increasingly developing NPC risk. Patients with allergic rhinitis might be associated with subsequent NPC in Taiwan. Those who had repeated visits for allergic rhinitis had even higher risk for NPC. Physicians should be aware of the link when assessing patients with allergic rhinitis.

Early Detection of Nasopharyngeal Carcinoma using IgA Anti-EBNA1 + VCA-p18 Serology assay

Nasopharyngeal carcinoma (NPC) is the most common head and neck malignancy in Indonesia. Overall, it ranks fourth in males and sixth in females as the most prevalent type of cancer in that country. The data show that in the year 2011, NPC incidence was considered to be intermediate (6.2/100,000 population per year). Through histopathologic examination, about 70 to 80% of these cases were found to be type III according to the WHO classificaton. NPC carries an excellent prognosis if treated early, but most patients presented with stage III to IV disease, which negatively affected the cure rate and increased the mortality rate. Epstein-Barr virus (EBV) IgA serology has been established as an effective marker for NPC. Therefore, biologic markers, DNA, and/or antibody-based diagnosis is needed to decrease NPC cases. A screening program needs to be developed that will identify people at high risk of NPC and those who are in the early stage of the disease. In this study, 20 samples were collected from post-therapy patients. An otolaryngologic examination, histopathology of nasopharyngeal tissue, and blood testing for serologic markers were performed. IgA anti-EBNA1 + VCA-p18 enzyme-linked immunosorbent assay showed positive impact as a tool for confirming the diagnosis of NPC, but it still has to be combined with other specific diagnostic tools for post-therapy monitoring and for determining prognosis.