Incidence Rates Of Nasopharyngeal Carcinoma Research Articles

Utility of CT Radiomics and Delta Radiomics for Survival Evaluation in Locally Advanced Nasopharyngeal Carcinoma with Concurrent Chemoradiotherapy.

A high incidence rate of nasopharyngeal carcinoma (NPC) has been observed in Southeast Asia compared to other parts of the world. Radiomics is a computational tool to predict outcomes and may be used as a prognostic biomarker for advanced NPC treated with concurrent chemoradiotherapy. Recently, radiomic analysis of the peripheral tumor microenvironment (TME), which is the region surrounding the gross tumor volume (GTV), has shown prognostic usefulness. In this study, not only was gross tumor volume (GTVt) analyzed but also tumor peripheral regions (GTVp) were explored in terms of the TME concept. Both radiomic features and delta radiomic features were analyzed using CT images acquired in a routine radiotherapy process. A total of 50 patients with NPC stages III, IVA, and IVB were enrolled between September 2004 and February 2014. Survival models were built using Cox regression with clinical factors (i.e., gender, age, overall stage, T stage, N stage, and treatment dose) and radiomic features. Radiomic features were extracted from GTVt and GTVp. GTVp was created surrounding GTVt for TME consideration. Furthermore, delta radiomics, which is the longitudinal change in quantitative radiomic features, was utilized for analysis. Finally, C-index values were computed using leave-one-out cross-validation (LOOCV) to evaluate the performances of all prognosis models. Models were built for three different clinical outcomes, including overall survival (OS), local recurrence-free survival (LRFS), and progression-free survival (PFS). The range of the C-index in clinical factor models was (0.622, 0.729). All radiomics models, including delta radiomics models, were in the range of (0.718, 0.872). Among delta radiomics models, GTVt and GTVp were in the range of (0.833, 0.872) and (0.799, 0.834), respectively. Radiomic analysis on the proximal region surrounding the gross tumor volume of advanced NPC patients for survival outcome evaluation was investigated, and preliminary positive results were obtained. Radiomic models and delta radiomic models demonstrated performance that was either superior to or comparable with that of conventional clinical models.

Effects of ambient temperature, relative humidity and absolute humidity on risk of nasopharyngeal carcinoma in China.

Nasopharyngeal carcinoma (NPC) has a unique geographic distribution. It is unknown whether meteorological factors are related to the incidence of NPC. To investigate the effect of ambient temperature, relative humidity (RH), and absolute humidity (AH) on the incidence of NPC, we collected the incidence rate of NPC in 2016 and meteorological data from 2006 to 2016 from 484 cities and counties across 31 provinces in China. Generalized additive models with quasi-Poisson regression and generalized linear models with natural cubic splines were employed respectively to elucidate the nonlinear relationships and specify the partial linear relationships. Subgroup and interactive analysis were also conducted. Temperature (R2 = 0.68, p < .001), RH (R2 = 0.47, p < .001), and AH (R2 = 0.70, p < .001) exhibited nonlinear correlations with NPC incidence rate. The risk of NPC incidence increased by 20.3% (95% confidence intervals [CI]: [18.9%, 21.7%]) per 1°C increase in temperature, by 6.3% (95% CI: [5.3%, 7.2%]) per 1% increase in RH, and by 32.2% (95% CI: [30.7%, 33.7%]) per 1 g/m3 increase in AH, between their the 25th and the 99th percentiles. In addition, the combination of low temperature and low RH was also related to increased risk (relative risk: 1.60, 95% CI: [1.18, 2.17]). Males and eastern or rural populations tended to be more vulnerable. In summary, this study suggests that ambient temperature, RH, and particularly AH are associated with the risk of NPC incidence.

Changing patterns of nasopharyngeal carcinoma incidence in Hong Kong: a 30-year analysis and future projections

BackgroundThis study aims to evaluate the relationship between age, period, and birth cohort with the incidence trends of Nasopharyngeal Carcinoma (NPC) in Hong Kong, make projections through 2030 and parse the drivers of the incidence.MethodsUsing data from the Hong Kong Cancer Registry, we used an age-period-cohort model to uniquely estimate age, period, and cohort effects on NPC incidence trends and make projections. We further assessed the drivers of NPC incidence using a validated decomposition algorithm.ResultsFrom 1991 to 2020, crude and age-standardized incidence rates of NPC decreased significantly. The net drifts showed significant downward trends for both sexes, and local drift declined in all age groups. Period and cohort rate ratios revealed monotonic declining patterns for both sexes. Projections suggested that NPC incidence will continue to decline. Population decomposition showed that while population growth and ageing have led to an increase in NPC cases, epidemiologic changes offset these increases, resulting in an encouraging downward trend in the incidence and new NPC cases in Hong Kong.ConclusionsThe period and cohort risk of NPC in Hong Kong decreased, and epidemiologic changes offset the contribution of demographic factors, resulting in a continued decline in NPC incidence and cases.

LncRNA HOXC-AS1 promotes nasopharyngeal carcinoma (NPC) progression by sponging miR-4651 and subsequently upregulating FOXO6

The incidence rate of nasopharyngeal carcinoma (NPC) is the highest among the malignant tumors of otorhinolaryngology, posing a huge burden to public health. Long noncoding RNAs (lncRNAs) exert an important role in tumorigenesis and the progression of various cancers. The present study found that HOXC-AS1 was highly expressed in NPC and in NPC cell lines, suggesting a critical role of HOXC-AS1 in NPC progression. In addition, the abundance of HOXC-AS1 was negatively correlated with the prognosis of NPC. To molecularly dissect the mechanism of HOXC-AS1 in NPC progression, we knocked down the expression of HOXC-AS1 in HNE1 and C666-1 cells. Then, we employed CCK8, colony-formation experiment and Transwell to investigate how the cell performed when HOXC-AS1 was knocked down. It could be observed that HOXC-AS1 knockdown decreases cell proliferation, migration and invasion, but induces cell apoptosis in NPC. We found that HOXC-AS1 could sponge miR-4651 subsequently binding FOXO6 and inhibiting its expression. Therefore, HOXC-AS1/miR-4651/FOXO6 may form a competing endogenous RNA (ceRNA) network that promotes NPC progression. In conclusion, our study demonstrates that HOXC-AS1 promotes NPC progression by sponging miR-4651 and regulating FOXO6 expression, thus providing potential pharmaceutical targets for developing new NPC treatments.

The global burden of nasopharyngeal carcinoma from 2009 to 2019: an observational study based on the Global Burden of Disease Study 2019

PurposeThe incidence and mortality rate of nasopharyngeal carcinoma (NPC) has changed in recent years. Our goal is to determine the epidemiological pattern of NPC to help policymakers allocate limited medical resources.MethodsDetailed information about NPC from 2009 to 2019 was collected from the Global Burden of Disease 2019 database. Age-standardized rates (ASRs) and corresponding estimated annual percentage changes (EAPCs) were calculated to assess NPC’s incidence and mortality trends.ResultsGlobally, there was a consistent increase in the NPC incidence cases from 2009 to 2019 (from 121.65 × 103 cases in 2009 to 176.50 × 103 cases in 2019, increasing by 45.09%). The age-standardized incidence rate (ASIR) of NPC increased from 1.81 in 2009 to 2.12 in 2019 (EAPC = 1.59, 95% CI 1.36–1.81). On the contrary, the mortality of NPC showed a downward trend (ASDR: 0.93 in 2009 and 0.86 in 2019; EAPC = − 0.63, 95% CI − 0.78 to − 0.48), and it was negatively correlated with the social demographic index (SDI) in most regions. Both incidence and mortality rates of high-incidence territories tended to be stable or decline. Males had significantly higher incidence and mortality of NPC than females. The number of patients with onset age greater than 50 years old accounted for the highest proportion. We found that smoking, occupational exposure to formaldehyde, and alcohol use were the main risk factors for NPC-related mortality.ConclusionGlobally, the incidence rate of NPC has been slightly increasing, while the mortality and disability-adjusted life years (DALYs) have been decreasing. NPC burden in high-middle and middle SDI areas was the heaviest. The current prevention strategy should be repositioned, and some countries should formulate more targeted approaches to reduce the current burden of NPC.

Nasopharyngeal carcinoma among the Bidayuh of Sarawak, Malaysia: History and risk factors.

Nasopharyngeal carcinoma (NPC) is a cancer of the epithelial cells lining the nasopharynx. The incidence of NPC has a distinct geographical distribution, mainly affecting the Chinese population of Southern China. In Malaysia, this cancer is exceptionally prevalent among males. There is a high incidence rate of NPC among the Bidayuh natives in Sarawak, Malaysia. Other than epidemiology reports, there has not been an article describing plausible cancer risk factors contributing to NPC within this native group. Researchers are still trying to understand the reasons the Bidayuh and Southern Chinese are highly susceptible to NPC. This article discusses the risk factors of developing NPC: Epstein-Barr virus infection, genetic predisposition, diet, environmental exposure and tobacco smoking. There is a need to improve the understanding of the role of risk factors to identify new ways to prevent cancer, especially among high-risk groups.

RNAi-mediated knockdown of PFK1 decreases the invasive capability and metastasis of nasopharyngeal carcinoma cell line, CNE-2

ABSTRACT Nasopharyngeal carcinoma (NPC) is the most prevailing malignancy of the head and neck with unique geographic distribution. Southern China has one of the highest incidence rates of NPC in the world. Although radiotherapy and chemotherapy are the most important treatment modalities for NPC, recurrence, and metastasis severely interfere with the survival quality of patients. It is much-needed to find an effective method of NPC treatment with a good prognosis such as gene therapy. PFK1, a key regulatory enzyme of glycolysis, is frequently shown to be amplified and overexpressed in a variety of human cancers. However, the function of PFK1 and molecular mechanism in NPC is elusive. Here, we knockdown PFK1 expression by utilizing DNA vector-based RNA Interference. Western blotting and real-time PCR show that the expression of PFK1 is efficiently down-regulated in both protein and mRNA levels by stable transfection with PFK1 siRNA expression vector. In addition, stable knockdown of PFK1 expression inhibits cell growth, induces apoptosis, decreases the invasive capability and metastasis in the CNE2 human NPC cell line. This present study finds the importance of PFK1 which can be worked as a novel target in NPC treatment and holds great potential to be extended to other malignant cancers.

Interleukin-18 promoter genotype is associated with the risk of nasopharyngeal carcinoma in Taiwan.

BackgroundThe incidence rate of nasopharyngeal carcinoma (NPC) has been documented to be high in Southeast Asia. Interleukin-18 (IL-18) is a multifunctional cytokine that augments interferon-γ production and acts as an important immunomediator in the development of several types of cancer.Patients and methodsThis case–control study evaluated the role of IL-18 in NPC at the DNA level by genotyping its promoter polymorphisms at positions -656, -607, and -137 in a Taiwanese population. A total of 176 patients with NPC and age- and gender-matched 352 noncancer controls were included in this study.ResultsThe CC genotype of the IL-18-607 polymorphism was found to be associated with significantly decreased risks of NPC compared to the AA genotype (crude OR =0.50, 95% CI =0.29–0.84, P=0.0093). This significant difference persisted even in the dominant and recessive models. A significantly lower C allele frequency at position -607 was detected in the NPC group(41.8% vs 50.3%; OR =0.77; 95% CI =0.63–1.04, P=0.0089). Regarding IL-18-656 and -137 polymorphisms, there were no differential distributions of their genotypes between the NPC and control groups. After substratification of the subjects according to their smoking, alcohol consumption, and areca chewing status, the genotype distribution of the IL-18-607 polymorphism was found to be different only among nonsmokers between the NPC and control subgroups.ConclusionThis study suggests that IL-18 plays an important role in the carcinogenesis of NPC in Taiwan and that the genotype–phenotype correlation of IL-18-607 polymorphism and its contribution to NPC need to be investigated further.

Genome-Wide Analysis of 18 Epstein-Barr Viruses Isolated from Primary Nasopharyngeal Carcinoma Biopsy Specimens.

Epstein-Barr virus (EBV) is a ubiquitous gammaherpesvirus that is highly prevalent in almost all human populations and is associated with many human cancers, such as nasopharyngeal carcinoma (NPC), Hodgkin's disease, and gastric carcinoma. However, in these EBV-associated cancers, only NPC exhibits remarkable ethnic and geographic distribution. We hypothesized that EBV genomic variations might contribute to the pathogenesis of different human cancers in different geographic areas. In this study, we collected 18 NPC biopsy specimens from the Hunan Province in southern China and de novo assembled 18 NPC biopsy specimen-derived EBV (NPC-EBV) genomes, designated HN1 to HN18. This was achieved through target enrichment of EBV DNA by hybridization, followed by next-generation sequencing, to reveal sequence diversity. These EBV genomes harbored 20,570 variations totally, including 20,328 substitutions, 88 insertions, and 154 deletions, compared to the EBV reference genome. Phylogenetic analysis revealed that all NPC-EBV genomes were distinct from other EBV genomes. Furthermore, HN1 to HN18 had some nonsynonymous variations in EBV genes including genes encoding latent, early lytic, and tegument proteins, such as substitutions within transmembrane domains 1 and 3 of LMP1, FoP_duplication, and zf-AD domains of ENBA1, in addition to aberrations in noncoding regions, especially in BamHI A rightward transcript microRNAs. These variations might have potential biological significance. In conclusion, we reported a genome-wide view of sequence variation in EBV isolated from primary NPC biopsy specimens obtained from the Hunan Province. This might contribute to further understanding of how genomic variations contribute to carcinogenesis, which would impact the treatment of EBV-associated cancer.IMPORTANCE Nasopharyngeal carcinoma (NPC) is highly associated with Epstein-Barr virus (EBV) infection and exhibits remarkable ethnic and geographic distribution. Hunan Province in southern China has a high incidence rate of NPCs. Here, we report 18 novel EBV genome sequences from viruses isolated from primary NPC biopsy specimens in this region, revealing whole-genome sequence diversity.

Milk consumption in relation to incidence of nasopharyngeal carcinoma in 48 countries/regions.

BackgroundDecreasing trends of nasopharyngeal carcinoma (NPC) incidence have been consistently reported in endemic populations but the etiology of NPC remains unclear. The objective of our study was to assess the international and local (Hong Kong) correlations of milk and dairy products per capita consumption with NPC incidence.MethodsWe conducted an ecological study in 48 countries/regions. Age standardized incidence rates of NPC were obtained from the Cancer Incidence in Five Continents. Dairy product consumption and Human Development Index were obtained from the Food and Agriculture Organization of the United Nations and the United Nations Development Programme. Spearman correlation, multivariate analysis and time-lagged analysis were performed.ResultsThe negative correlations between milk consumption and decreased age standardized incidence rates of NPC were observed in the 48 countries/regions adjusting for Human Development Index in endemic countries/regions. In Hong Kong, multivariate analysis, after adjusting for other potential confounders, including salted fish, cigarette, vegetable consumption and socioeconomic status, showed consistently negative and significant correlations between milk consumption and NPC incidence (The strongest coefficient (β) was observed at 10-year lag in males [β = −0.439; P < 0.01] and in females [β = −0.258; P < 0.01]).ConclusionsOur study showed the correlations on milk consumption per capita and against lower risk of NPC in 48 countries/regions and in Hong Kong. These hypothesis-generating results could support further studies on individual exposures and the disease.

Abstract 3712: Incidence trend of NPC using age-period-cohort analysis from1987 to 2011 in Sihui County, southern China

Abstract In the past several decades, declining incidence rates of NPC have been observed in Chinese populations in Hong Kong, Taiwan, Los Angeles, and Singapore.However, the incidents rates in southern China have remained stable.This study describes the incidence trend of nasopharyngeal carcinoma (NPC) using age-period-cohort (APC) analysis from 1987 to 2011 in Sihui County, southern China. Age-standardized incidence rates compared with the world standard population were examined in both males and females. A Joinpoint regression analysis was conducted to quantify the changes in incidence trends. A Poisson regression APC model was used to assess the age, period, and birth cohort effects on incidence. Age-standardized incidence rates during the study period were 30.29 and 13.09 per 100,000 for males and females, respectively. The incidence rates of NPC remained stable with a non statistical significant average annual percentage change of 0.2% for males and -1.6% for females throughout the entire period. A statistically significant increase (estimated annual percentage change, 6.8%; 95% confidence interval, 0.1%-14.0%) was observed from 2003 to 2009 for males. The incidence of NPC increased with advancing age up to ages 50-59 and decreased at ages &amp;gt;60 years. The curves of NPC incidence by period were virtually flat for males and females. The curve for males by birth cohort showed an increase from the 1922 to 1952 cohort and a decrease thereafter. In females, there was an undulating increase in relative risks from the 1922 to 1972 cohort. In conclusion, the incidence trends for NPC remained generally stable in Sihui from 1987 to 2011, with an increase during 2003-2009. The relative risks of NPC increased in younger female cohorts, the underlying reason of which is expected to be further explored. Note: This abstract was not presented at the meeting. Citation Format: Qing Liu, Sumei Cao, Qihong Huang, Lifang Zhang, Yanhua Li, Shanghang Xie. Incidence trend of NPC using age-period-cohort analysis from1987 to 2011 in Sihui County, southern China. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3712. doi:10.1158/1538-7445.AM2015-3712

Progresses and Challenges in Chemotherapy for Loco- Regionally Advanced Nasopharyngeal Carcinoma.

Incidence rates of nasopharyngeal carcinoma are high in Indonesia, Singapore and South-Eastern China. Chemoradiotherapy has been the standard regimen for locally advanced nasopharyngeal carcinoma according to guidelines from the National Comprehensive Cancer Network. Recently, advances in the management of nasopharyngeal carcinoma have transferred into better treatment outcomes. Most phase III clinical trials support the addition of concurrent chemotherapy to radiotherapy for the initial treatment of these patients. Studies evaluating effects and toxicity of concurrent chemotherapy with different regimens have been reported. However, the status of adding adjuvant chemotherapy or induction chemotherapy remains controversial. Recent studies have shown that adjuvant chemotherapy with two or three cycles may improve survival for nasopharyngeal carcinoma with stage N2-3 disease or with persistently detectable plasma EBV DNA after radiotherapy. This review examines the pertinent issues and latest studies concerning the management of loco-regionally advanced NPC, regarding concurrent chemotherapy, adjuvant chemotherapy, and induction chemotherapy in decades.

Nasopharyngeal carcinoma incidence in North Tunisia: negative trends in adults but not adolescents, 1994-2006.

Nasopharyngeal carcinoma (NPC) is the second most common neoplasm of head and neck in Tunisia. The distribution is bimodal with a first period occurrence between 15 and 20 years old and a second peak at around 50 years of age. Undifferentiated carcinoma of nasopharynx type III (UCNT) is the predominant histological type (93.4%). Data of cancer registry of North Tunisia confirmed that it is an intermediate risk area for NPC with overall ASRs of 3.6 and 1.6/100,000 respectively in males and females. This study aimed to present the evolution of incidence rate of nasopharyngeal carcinoma over a period of 12 years (1994-2006). Data of cancer registry of North Tunisia (NTCR), covering half of the Tunisian population, were used to determine evolution of NPC incidence, calculated by 5 year periods. The estimated annual percentage change (EAPC) was used as an estimate of the trend. To best summarize the behavior or the data trend across years, we used a join-point regression program. Between 1994 and 2006, we observed negative annual average change of standardized incidence in men and women (-3.3% and -2.7%) also for the standardized incidences which showed a rather important decline (26.4% in males and 22.3% in females). The truncated age standardized incidence rate of NPC in adults aged of 30 years old and more (N=1209) decreased by -0.4% per year from 1994 to 2006 over time in north Tunisia dropping from 6.09 to 4.14 person-years. However, the rate was relatively stable during this period among youths aged 0-29 years (N=233) in both sexes. NPC demonstrated a favorable evolution from 1994-2006 probably due to a improvement in socioeconomic conditions.

Time trends of nasopharyngeal carcinoma in urban Guangzhou over a 12-year period (2000-2011): declines in both incidence and mortality.

Nasopharyngeal carcinoma (NPC) is an uncommon disease in most countries but occurs with much greater frequency in southern China. This study aimed to examine the secular trends of NPC in urban Guangzhou over the time period of 2000-2011 using data from the Guangzhou Cancer Registry. Age-adjusted annual incidence rates of NPC were calculated by the direct method using the WHO World Standard Population (1960) as the reference. The average annual percentage change (AAPC) was used as an estimate of the trend. A total of 7,532 new cases of NPC and 3,449 related deaths were registered. In both genders, the peak incidence occurred in the 50- to 59-year age group, and this age distribution pattern remained similar throughout. The AAPC in NPC incidence rates was -3.26% (95% CI: -5.4%--1.1) for males and -5.74% (95% CI: -8.9%--2.5) for females, resulting in a total decrease of 39.3% (from 22.14 to 13.44 per 100,000 population) for males and 48.6% (from 10.1 to 5.18 per 100,000 population) for females over this 12-year period. The AAPCs in NPC mortality rates were -4.62% (95%CI: -3.5%--5.7) for males and -6.75% (95% CI: -5.2%--8.3) for females, resulting in a total decrease of -46.1% (from 12.1 to 6.54 per 100,000 population) for males and 51.7% (from 4.14 to 2.00 per 100,000 population) for females. The age-adjusted incidence and mortality rates of NPC declined during 2000-2011 in urban Guangzhou but remained high. Future efforts to improve prevention, early detection and treatment strategies are needed.

Abstract 1512: Role of Epstein-Barr virus in nasopharyngeal carcinoma under metabolic stress.

Abstract Most nasopharyngeal carcinoma (NPC) biopsies contain a human pathogen named as Epstein-Barr virus (EBV). EBV infection is considered as an early event involved in the pathogenesis of NPC. However, the close association of EBV with NPC is a paradox. EBV infection is common that occurs in ≥95% of the world's population, yet the incidence rate of NPC is rare worldwide and is only seen in Cantonese speaking ethnic groups in Southern Asia. The mechanisms that regulate EBV infection of NPC/pre-malignant NP cells including the events involved in latency and lytic activation (either in vitro or in vivo) are not well-defined. Expressions of latent and lytic EBV genes have been shown to have variable effects on the biology and malignant properties of EBV-infected cells. Hypoxia and nutrient-starvation are common physiological stresses within tumours and may have impact on regulation of latent and lytic EBV infection in NPC cells. Here we report that the levels of hypoxia-inducible factor, HIF-1α protein, a prime hypoxic-stress responsive marker for mammalian cells, are higher in EBV-infected NPC/pre-malignant NP cell lines under hypoxia than their non-infected counterparts, which may imply an enhanced survival ability of EBV-infected NP cells. The alteration in gene expression profiles of host cells and expression of EBV genes observed in infected cells may be responsible for the stabilization of HIF-1α and vice versa. Moreover, EBV infection enhances the tumour growth rate and size of NPC cells xenografts in nude mice. The main stem of this study is to examine whether there is a differential response between EBV-infected and non-infected NP cells towards various metabolic stresses. Through studying this project, the mechanism and function of HIF-1α stability by EBV infection will be explored, which is expected to help characterizing the role of EBV in transformation of epithelial cells and how EBV infection may enhance NPC cells to survive inside a tumour core. Citation Format: VMY Lau, SW Tsao. Role of Epstein-Barr virus in nasopharyngeal carcinoma under metabolic stress. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 1512. doi:10.1158/1538-7445.AM2013-1512 Note: This abstract was not presented at the AACR Annual Meeting 2013 because the presenter was unable to attend.

The Criteria to Confirm the Role of Epstein-Barr Virus in Nasopharyngeal Carcinoma Initiation

Epstein-Barr virus (EBV) is associated with nasopharyngeal carcinoma (NPC), but it remains obscure whether EBV is a viral cause of, or only an accompaniment of, NPC. We will discuss the accumulated evidence pointing to the relationship between EBV infection and NPC initiation from epidemiologic, pathogenic, molecular oncogenic, and experimental animal studies. We believe that convincing evidence from these perspectives must be provided before we can ascertain the causal role of EBV infection in NPC. Specifically, (1) epidemiological studies should reveal EBV infection as a risk factor; (2) the introduction of EBV into an animal model should produce NPC; (3) in the animal model NPC, the main molecular event(s) or the involved signaling pathway(s) should be identical to that in human NPC; and (4) finally and most importantly, prevention of EBV infection or clearance of EBV from infected individuals must be able to reduce the incidence rate of NPC.

Time trends and age–period–cohort analyses on incidence rates of nasopharyngeal carcinoma during 1993–2007 in Wuhan, China

Background: Declines in incidence rates of nasopharyngeal carcinoma (NPC) were observed in Hong Kong and Taiwan but not other high-risk regions in China, while evidences from low-risk regions in China are still lacking. This study aimed to examine the time trends (1993–2007) of NPC in Wuhan (a low-risk region) and assess the birth cohort and calendar period effects on the observed temporal trends. Method: Using data from Wuhan Cancer Registry, age-standardized annual incidence rates of NPC were calculated by the direct method using the WHO World Standard Population (2000) as the reference. Trend in incidence rates of NPC during 1993–2007 was evaluated. Age–period–cohort models were also applied to assess the effects of age, calendar time and birth cohort on the observed temporal trends. Results: A total of 1685 new NPC cases (1210 males and 475 females) were diagnosed during 1993–2007 in Wuhan. The annual percentage change in incidence rates of NPC were 0.15% (95% confidence interval: −3.88% to 4.34%) for males and −1.17% (95% confidence interval: −4.85% to 2.66%) for females. No obvious cohort or period effect on the incidence rates of NPC was observed. Conclusion: The incidence rates of NPC remained stable during 1993–2007 in Wuhan, a low-risk region in China.

SP3-4 Incidence of nasopharyngeal carcinoma in the north of Tunisia: tendency and projections until 2024

Nasopharyngeal carcinoma (NPC) is the second neoplasm of ORL site in Tunisia with a bimodal distribution and a first period occurrence between 15 and 20 years old and a second...

Risk factors for the occurrence of undifferentiated carcinoma of nasopharyngeal type: A case-control study

The incidence rate of nasopharyngeal carcinoma in Serbia is less than one per 100,000 citizens, which classifies it as a region with low incidence for this disease. The aim of this study was to test some hypotheses of the risk factors for undifferentiated carcinoma of nasopharyngeal type (UCNT) in the low incidence population. A case-control study was used for the research. The study included 45 cases with histopathological diagnosis of UCNT and 90 controls. Cases and the controls were individually matched by sex, age (+/- 3 years), and place of residence (city-village). Data were gathered about sociodemographic characteristics, occupational exposure to harmful agents, habits, diet, personal history, and family history. In the analysis of the data, conditional univariate and multivariate logistic regression analyses were applied. According to the results of multivariate logistic regression analysis UCNT was significantly positively associated with "passive smoking" of tobacco in the family during childhood, frequent consumption of industrially manufactured food additives for enhancing flavour and frequent consumption of white bread. UCNT was significantly negatively associated with frequent consumption of margarine, olive oil and cornbread. In our low incidence population, an independent risk factor for the occurrence of UCNT was "passive smoking" of tobacco in the family during childhood, use of industrially manufactured food with additives for enhancing flavour and consumption of white bread. Multicentric study enrolling a greater number of cases would be desirable.

Incidence of nasopharyngeal carcinoma in Chinese immigrants, compared with Chinese in China and South East Asia: review

To evaluate the literature and to compare published data on age-standardised incidence rates of nasopharyngeal carcinoma in Chinese people living in and outside China. Systematic review of incidence rate studies and statistical incidence data concerning nasopharyngeal carcinoma in Chinese populations from 1960 to 2008. Sixteen papers were identified from the PubMed, Embase and Scopus electronic databases and from a hand search of the reference lists of the retrieved papers. Further searches for raw data on age-specific and age-standardised incidence rates of nasopharyngeal carcinoma were conducted. Textbooks on relevant subjects were referred to for background information. A total of 19 papers met the inclusion criteria. Seven studies included raw data on age-specific and age-standardised incidence rates of nasopharyngeal carcinoma in Chinese people. Twelve other studies reported on changes in the incidence of nasopharyngeal carcinoma in Chinese populations in selected countries or regions. Studies on age-specific and age-standardised rates obtained data from individual registries. Studies on incidence rates obtained data from hospital records, cancer notifications (from all sections of the medical profession), pathology records and death certificates. The results showed a decline in age-standardised incidence rates of nasopharyngeal carcinoma in Chinese immigrant populations, compared with Chinese people in China. There was also a trend towards decreasing incidence the further the population had immigrated. Thus, the incidence of nasopharyngeal carcinoma in Singaporean Chinese was higher than that in Hawaiian Chinese, and that in Hawaiian Chinese was higher than that in Californian Chinese. This review found a decreasing trend in the incidence of nasopharyngeal carcinoma in Chinese migrants living in countries with a low risk of the disease.