Nasopharyngeal Carcinoma In Taiwan Research Articles

Effect of Chinese Herbal Medicine Therapy on Overall and Cancer Related Mortality in Patients With Advanced Nasopharyngeal Carcinoma in Taiwan

Nasopharyngeal carcinoma (NPC) is a head and neck cancer involving epithelial squamous-cell carcinoma of the nasopharynx that mainly occurs in individuals from East and Southeast Asia. We investigated whether Chinese herbal medicine (CHM) as a complementary therapy offers benefits to these patients. We retrospectively evaluated the Taiwan Cancer Registry (Long Form) database for patients with advanced NPC, using or not using CHM, between 2007–2013. Cox proportional-hazard model and Kaplan‒Meier survival analyses were applied for patient survival. CHM-users showed a lower overall and cancer-related mortality risk than non-users. For advanced NPC patients, the overall mortality risk was 0.799-fold for CHM-users, after controlling for age, gender, and Charlson comorbidity index (CCI) score (Cancer stages 3 + 4: adjusted hazard ratio [aHR]: 0.799, 95% confidence interval [CI]: 0.676–0.943, p = 0.008). CHM-users also showed a lower cancer-related mortality risk than non-users (aHR: 0.71, 95% CI: 0.53–0.96, p = 0.0273). Association rule analysis showed that CHM pairs were Ban-Zhi-Lian (BZL; Scutellaria barbata D.Don) and For single herbs, Bai-Hua-She-She-Cao (Herba Hedyotis Diffusae; Scleromitrion diffusum (Willd.) R.J.Wang (syn. Hedyotis diffusa Willd.) and Mai-Men-Dong (MMD; Ophiopogon japonicus (Thunb.) Ker Gawl.), and Gan-Lu-Yin (GLY) and BHSSC. Network analysis revealed that BHSSC was the core CHM, and BZL, GLY, and Xin-Yi-Qing-Fei-Tang (XYQFT) were important CHMs in cluster 1. In cluster 2, ShengDH, MMD, Xuan-Shen (XS; Scrophularia ningpoensis Hensl.), and Gua-Lou-Gen (GLG; Trichosanthes kirilowii Maxim.) were important CHMs. Thus, as a complementary therapy, CHM, and particularly the 8 CHMs identified, are important for the treatment of advanced NPC patients.

Correction: Identification of a Novel, EBV-based Antibody Risk Stratification Signature for Early Detection of Nasopharyngeal Carcinoma in Taiwan

In the original version of [this article][1] ([1][2]), the left panel of Fig. 2 was incorrectly labeled: the BFRF1 IgG antibody was incorrectly labeled as the BALF2 IgG antibody, and the corresponding sentence in the text was also incorrect. These errors have been corrected in the latest online HTML

Chinese herbal products for nasopharyngeal carcinoma: A population-based registry study

IntroductionThe use of traditional Chinese medicine (TCM) as a complementary and alternative medicine for the treatment of nasopharyngeal carcinoma (NPC) and its treatment-related side effects has been increasing. We investigated the utilization of Chinese herbal products (CHPs) for NPC in Taiwan. MethodsThis retrospective, nationwide, population-based study was conducted and obtained data from the Registry for Catastrophic Illnesses Patient Database from 2001 through 2011 in Taiwan. The top ten most frequently prescribed formulae and single CHPs for treating NPC were assessed. Demographic characteristics, including sex and age at diagnosis of NPC, were examined, together with existing comorbidities. Descriptive statistics and multiple logistic regression analysis were employed to estimate the adjusted odds ratios (aORs) for CHP utilization. ResultsIn total, 17,816 patients aged ≥20 years were newly diagnosed with NPC. Of these, 4749 patients used TCM outpatient services for NPC treatment. NPC patients using TCM were more likely to be women (aOR, 1.47; 95% CI, 1.37–1.58), young, and residents of central Taiwan (aOR, 1.49; 95% CI, 1.37–1.62) and southern Taiwan (aOR, 1.12; 95% CI, 1.05–1.21). The most commonly prescribed formula CHP was Gan-Lu-Yin (2.99%), followed by Xin-Yi-Qing Fei-Tang (1.52%) and Shan-Shen-Mai-Men-Dong-Tang (0.92%). The most commonly prescribed single CHP was Bai Hua She She Cao (Hedyotis diffusa) (3.23%), followed by Xuan Shen (Scrophularia ningpoensis) (2.24%) and Mai Men Dong (Radix Ophiopogonis) (1.84%). ConclusionsThese findings provide information regarding personalized therapies for NPC and can promote further clinical experiments and pharmacological research on CHPs for NPC treatment in Taiwan.

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.

Identification of a Novel, EBV-Based Antibody Risk Stratification Signature for Early Detection of Nasopharyngeal Carcinoma in Taiwan.

Background Epstein-Barr virus (EBV) is necessary for the development of nasopharyngeal carcinoma (NPC). By adulthood, approximately 90% of individuals test EBV-positive, but only a fraction develop cancer. Factors that identify which individuals are most likely to develop disease, including differential antibody response to the virus, could facilitate detection at early stages when treatment is most effective.Methods We measured anti-EBV IgG and IgA antibody responses in 607 Taiwanese individuals. Antibodies were measured using a custom protein microarray targeting 199 sequences from 86 EBV proteins. Variation in response patterns between NPC cases and controls was used to develop an antibody-based risk score for predicting NPC. The overall accuracy [area under the curve (AUC)] of this risk score, and its performance relative to currently used biomarkers, was evaluated in two independent Taiwanese cohorts.Findings Levels of 60 IgA and 73 IgG anti-EBV antibodies differed between stage I/IIa NPC cases and controls (P < 0.0002). Risk prediction analyses identified antibody targets that best discriminated NPC status-BXLF1, LF2,BZLF1, BRLF1, EAd, BGLF2, BPLF1, BFRF1, and BORF1. When combined with currently used VCA/EBNA1 IgA biomarkers, the resulting risk score predicted NPC with 93% accuracy (95% CI, 87%-98%) in the general Taiwanese population, a significant improvement beyond current biomarkers alone (82%; 95% CI, 75%-90%, P ≤ 0.01). This EBV-based risk score also improved NPC prediction in genetically high-risk families (89%; 95% CI, 82%-96%) compared with current biomarkers (78%; 95% CI, 66%-90%, P ≤ 0.03).Interpretation We identified NPC-related differences in 133 anti-EBV antibodies and developed a risk score using this microarray dataset that targeted immune responses against EBV proteins from all stages of the viral life cycle, significantly improving the ability to predict NPC. Clin Cancer Res; 24(6); 1305-14. ©2017 AACR.

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.

Human papilloma virus detection in neoplastic and non-neoplastic nasopharyngeal tissues in Taiwan

BackgroundHuman papilloma virus (HPV) has been implicated in the carcinogenesis and prognosis of certain head and neck cancers. Whether it also has a role in the pathogenesis of nasopharyngeal carcinoma...

Use of Chinese Medicine Among Survivors of Nasopharyngeal Carcinoma in Taiwan

Hypotheses. The authors hypothesized that the use of alternative medicine, in the form of Chinese medicine (CM), among patients in the continuing care phase of nasopharyngeal carcinoma (NPC) in Taiwan is higher than the use in a matched control group of noncancer individuals. This was a case-control study. Using a population-based claim database, the authors identified 181 long-term survivors of NPC and 905 matched controls. They obtained information on CM use and associated cost as outcome measures. Descriptive analysis and regression models were applied to examine the association between NPC and the outcome measures. The unadjusted CM initiation (34% vs 32%; P = .54), intensity of use (2.15 vs 1.73 visits; P = .37), and cost (US$79 vs US$58; P = .16) were higher for patients in the NPC group than for those in the control group. Regression analyses suggested that the NPC group had significantly more CM visits (1.01; 95% confidence interval = 0.07-1.96), and more than 50% of these visits were related to cancer. The authors confirmed their hypotheses that the use of CM in the continuing care phase by patients with NPC in Taiwan was higher than the use in their matched, noncancer counterparts. These findings suggest that current clinical surveillance strategies for NPC might not meet patients' physical and emotional needs.

Familial Tendency and Risk of Nasopharyngeal Carcinoma in Taiwan: Effects of Covariates on Risk

In the present study, the authors compared the long-term risk of nasopharyngeal carcinoma (NPC) of male participants in an NPC multiplex family cohort with that of controls in a community cohort in Taiwan after adjustment for anti-Epstein-Barr virus (EBV) seromarkers and cigarette smoking. A total of 43 incident NPC cases were identified from the 1,019 males in the NPC multiplex family cohort and the 9,622 males in the community cohort, for a total of 8,061 person-years and 185,587 person-years, respectively. The adjusted hazard ratio was 6.8 (95% confidence interval (CI): 2.3, 20.1) for the multiplex family cohort compared with the community cohort. In the evaluation of anti-EBV viral capsid antigen immunoglobulin A and anti-EBV deoxyribonuclease, the adjusted hazard ratios were 2.8 (95% CI: 1.3, 6.0) and 15.1 (95% CI: 4.2, 54.1) for those positive for 1 EBV seromarker and positive for both seromarkers, respectively, compared with those negative for both EBV seromarkers. The adjusted hazard ratio was 31.0 (95% CI: 9.7, 98.7) for participants who reported a family history of NPC and who were anti-EBV-seropositive compared with individuals without such a history who were anti-EBV-seronegative. The findings suggest that both family history of NPC and anti-EBV seropositivity are important determinants of subsequent NPC risk and that the effect of family history on NPC risk cannot be fully explained by mediation through EBV serologic responses.

Dynamic contrast-enhanced and T2-weighted magnetic resonance imaging study of the correlation between tumour angiogenesis and growth kinetics

Accumulating evidence indicates that tumour growth is angiogenesis-dependent. Non-invasive assessment of the relationship between tumour growth and associated angiogenesis is essential for diagnosis and for therapeutic interventions. We utilized a combination of high-resolution T2-weighted and dynamic contrast-enhanced magnetic resonance imaging to investigate the dynamics of angiogenesis during tumour growth in a mouse tumour model expressing Epstein-Barr virus-encoded latent membrane protein 1 isolated from a nasopharyngeal carcinoma in Taiwan. Serial imaging acquisitions were performed starting on the third day after subcutaneous implantation of tumours, through day 28. We observed a progressive increase in tumour volume until day 14, followed by rapid and exponential growth. The volume transfer constant, K(trans), also increased significantly on day 14, and then gradually decreased, suggesting that the angiogenic switching occurs prior to significant tumour growth. At the initial stage, the K(trans) values were significantly higher in the tumour peripheral region than in the tumour core, but, during tumour growth, the K(trans) values in the region between the tumour periphery and core gradually increased, becoming larger than those of the periphery. These results demonstrate that the ability to perform repeated measurements assessing the correlation between tumour growth kinetics and tumour angiogenesis makes it possible to determine the critical time of angiogenic switching prior to rapid tumour growth, as well as suggesting the timing of therapy.

Robustness of inference on measured covariates to misspecification of genetic random effects in family studies.

Family studies to identify disease-related genes frequently collect only families with multiple cases. It is often desirable to determine if risk factors that are known to influence disease risk in the general population also play a role in the study families. If so, these factors should be incorporated into the genetic analysis to control for confounding. Pfeiffer et al. [2001 Biometrika 88: 933-948] proposed a variance components or random effects model to account for common familial effects and for different genetic correlations among family members. After adjusting for ascertainment, they found maximum likelihood estimates of the measured exposure effects. Although it is appealing that this model accounts for genetic correlations as well as for the ascertainment of families, in order to perform an analysis one needs to specify the distribution of random genetic effects. The current work investigates the robustness of the proposed model with respect to various misspecifications of genetic random effects in simulations. When the true underlying genetic mechanism is polygenic with a small dominant component, or Mendelian with low allele frequency and penetrance, the effects of misspecification on the estimation of fixed effects in the model are negligible. The model is applied to data from a family study on nasopharyngeal carcinoma in Taiwan.

Association of HLA class I and II alleles and extended haplotypes with nasopharyngeal carcinoma in Taiwan.

Nasopharyngeal carcinoma (NPC), which occurs at a disproportionately high rate among Chinese individuals, is associated with Epstein-Barr virus (EBV). Human leukocyte antigen (HLA) polymorphisms appear to play a role in NPC, because they are essential in the immune response to viruses. We used high-resolution HLA genotyping in a case-control study in Taiwan to systematically evaluate the association between various HLA alleles and NPC. We matched 366 NPC case patients to 318 control subjects by age, sex, and geographic residence. Participants were interviewed and provided blood samples for genotyping. High-resolution (polymerase chain reaction-based) genotyping of HLA class I (A and B) and II (DRB1, DQA1, DQB1, and DPB1) genes was performed in two phases. In phase I, 210 case patients and 183 control subjects were completely genotyped. In phase II, alleles associated with NPC in the phase I analysis were evaluated in another 156 case patients and 135 control subjects. Extended haplotypes were inferred. We found a consistent association between HLA-A*0207 (common among Chinese but not among Caucasians) and NPC (odds ratio [OR] = 2.3, 95% confidence interval [CI] = 1.5 to 3.5) but not between HLA-A*0201 (most common HLA-A2 allele in Caucasians) and NPC (OR = 0.79, 95% CI = 0.55 to 1.2). Individuals with HLA-B*4601, which is in linkage disequilibrium with HLA-A*0207, had an increased risk for NPC (OR = 1.8, 95% CI = 1.2 to 2.5) as did individuals with HLA-A*0207 and HLA-B*4601 (OR = 2.8, 95% CI = 1.7 to 4.4). Individuals homozygous for HLA-A*1101 had decreased risks for NPC (OR = 0.24, 95% CI = 0.13 to 0.46). The extended haplotype HLA-A*3303-B*5801/2-DRB1*0301-DQB1*0201/2-DPB1*0401, specific to this ethnic group, was associated with a statistically significantly increased risk for NPC (OR = 2.6, 95% CI = 1.1 to 6.4). The restriction of the association of HLA-A2 with NPC to HLA-A*0207 probably explains previously observed associations of HLA-A2 with NPC among Chinese but not Caucasians. The extended haplotypes associated with NPC might, in part, explain the higher rates of NPC in this ethnic group.

Microsatellite alteration at chromosome 11 in primary human nasopharyngeal carcinoma in Taiwan.

Nasopharyngeal carcinoma (NPC) is one of the common cancers in Taiwan but is rare in western countries. The development of NPC involves multiple genetic changes in tumorigenesis and progression of the disease. To better understand genetic alterations in chromosome 11 which occur in human (NPC), we examined tumor specimens and corresponding non-cancerous tissue from 30 cases of NPC, using five microsatellite polymorphic markers whose location has previously been defined. To determine the clinical characteristics of MSI(+) or LOH, we performed correlation analysis of the findings with clinicopathological parameters. Loss of heterozygosity (LOH) was identified in 18 (60%) of 30 cases on at least one of the five markers. A high frequency of LOH was found at the two loci: D11S912 (7/30, 23.33%) and D11S934 (6/30, 20.00%), both of which are located within 11q23-24. We also found that 14 specimens (14/30, 46.67%) exhibited microsatellite instability (MSI(+)). Five (5/30, 16.67%) specimens exhibited MSI(+) in the transformation growth factor beta receptor type II (TGF-beta RII) exon 3 which also exhibited on chromosome 11. LOH was found to be significantly correlated with the T (tumor size) value (P=0.022) of Ho's system. MSI(+) showed a significant correlation with the N (lymph node) value of the UICC system (P=0.031). Our results suggest that multiple putative tumor suppressor genes on chromosome 11 play a role in the development of NPC. MSI(+) expression showed a predisposition to occur in the late stage of NPC while LOH tended to occur in early stages of NPC. The behavior of mutated TGF-beta RII exon 3, which appeared to serve as a dysfunction brake during nasopharyngeal carcinogenesis, may be a target gene in the defected mismatch repair system.

Dietary exposure to nitrite and nitrosamines and risk of nasopharyngeal carcinoma in Taiwan.

Previous studies of nasopharyngeal carcinoma (NPC) have found elevated risks with higher consumption of salted fish and preserved foods, particularly during childhood. These foods can contain high levels of nitrosamines; however, most studies have not estimated exposure to nitrosamines directly. We conducted a case-control study in Taiwan to evaluate dietary intakes and NPC risk. A total of 375 cases (99% response rate) and 327 controls (88% response rate) were interviewed about their diet as an adult and at age 10 using a food-frequency questionnaire. We interviewed mothers of participants about their child's diet at age 10, age 3 and during weaning and the mother's diet while she was breast-feeding. Mothers of 96 cases and 120 controls were interviewed. Nitrosamine and nitrite levels were assigned to 66 foods based on published values. Intake of nitrosamines and nitrite as an adult was not associated with risk of NPC. High intakes of nitrosamines and nitrite during childhood and weaning were associated with increased risks of NPC for foods other than soy products. Adjusted odds ratios for the highest quartile were 2.2 [95% confidence interval (CI) 0.8-5.6] for age 10, 2.6 (95% CI 1.0-7.0) for age 3 and 3.9 (95% CI 1.4-10.4) for weaning diet. Intakes of nitrite and nitrosamines from soybean products during childhood and weaning were inversely associated with risk. Soybeans contain known inhibitors of nitrosation, and thus may explain the inverse association we observed. Our results suggest that nitrosamine and nitrite intake during childhood may play a role in the development of NPC.

Deletions and single-base mutations within the carboxy-terminal region of the latent membrane protein 1 oncogene in Epstein-Barr virus-related gastric cancers of southern Japan.

The 30-base pair (bp) deletion of the cytoplasmic carboxy-terminal domain of the latent membrane protein 1 (LMP-1) gene was analyzed in 37 frozen tissues from patients with Epstein-Barr virus (EBV)-related gastric cancer and 18 throat washings from healthy adults in southern Japan. The 30-bp deletion was identified in 33 (91.7%) of 36 specimens of EBV-related gastric cancers and in 15 (83.3%) of 18 throat washings from healthy adults. In one case of gastric cancer, an additional 9-bp deletion was identified downstream of the 30-bp deletion. From the last transmembrane domain to the end of the carboxy terminal of LMP-1, mutations were examined in 37 cases of gastric cancers and in three cases of throat washings. Twenty-eight nonsilent mutations were identified in this region of EBV-related gastric cancer and throat washings. Five nonsilent mutations at positions 168,755, 168,746, 168,687, 168,357, and 168,355 were identified in all 30-bp-deleted cases of EBV-related gastric cancers and throat washings. However, these nonsilent mutations were not identified in three patients without the 30-bp deletion. Although the deletion and single-base mutations of the LMP-1 gene in gastric cancers and throat washings were similar to those of nasopharyngeal carcinoma in Taiwan and China, more single-base mutations were found in southern Japan. These data indicate that high prevalence of the 30-bp deletion of the LMP-1 gene in gastric cancers may reflect the prevalence of the deletion variant in the normal population in southern Japan.

Cigarette smoking, alcohol consumption and risk of nasopharyngeal carcinoma in Taiwan.

Nasopharyngeal carcinoma (NPC) is rare in most countries but occurs with relatively high frequency among southern Chinese populations throughout the world. A case-control study of NPC was conducted in Taiwan to investigate the importance of active and passive cigarette exposure and alcohol consumption as risk factors for this disease. 375 histologically confirmed incident NPC cases (99% response rate) were prospectively identified from two hospitals in Taipei between July 1991 and December 1994 and administered a detailed questionnaire. 327 healthy community controls individually matched to cases on sex, age and residence were selected (88% response rate). After multivariate adjustment, the odds ratio (OR) and 95% confidence interval (CI) was 1.7 (1.1-2.9 with p = 0.03 for increasing dose-response) for those who smoked for > or = 25 years compared with non-smokers. Passive smoking during childhood or adult life was not associated with an increased risk of disease. Alcohol consumption was not associated with NPC risk. The OR for subjects with > or = 15 grams of ethanol per day compared to non-drinkers was 1.1 (95% CI = 0.7-1.7). Our results suggest that long term cigarette smoking is associated with NPC but that low level exposure to cigarette smoke via passive exposure and alcohol consumption are not associated with disease risk.

The probability of diagnosis of nasopharyngeal carcinoma in patients with only adult-onset otitis media with effusion.

This study tried to assess the probability of nasopharyngeal carcinoma (NPC) being present in adults with only otitis media with effusion (OME) and evaluate the necessity of nasopharyngeal biopsy in Taiwanese adults with only OME. The clinical features of patients with known OME were analyzed and the incidence of nasopharyngeal carcinoma in adults with only OME was assessed. The clinical features of 36 adults with OME but without other symptoms and signs suggestive of NPC who presented to the Kaohsiung Medical College Hospital Department of Otorhinolaryngology between December 1995 and February 1997 were analyzed. Two of these patients had biopsy-proven non-keratinizing carcinomas. OME was caused by upper respiratory infection in 8 patients (22.2%), chronic paranasal sinusitis in 5 (13.9%), allergic rhinitis in 5 (13.9%), NPC in 2 (5.6%), other etiologies in 5 (13.9%) and by unknown etiologies in 11 (30.5%). The incidence of NPC in adults with OME but no other symptoms and signs suggestive of NPC was 5.6% (2 out of 36 patients). It was higher than other reports because NPC has a high prevalence in Taiwan. Therefore, biopsy of the post-nasal space in adults with only OME when NPC is strongly suspected is necessary for the early diagnosis of NPC in Taiwan. We conclude that Taiwanese adults with only OME for which the cause is unclear should be subjected to an examination and biopsy of the nasopharynx to exclude NPC.

Salvage surgery for recurrent nasopharyngeal carcinoma.

To assess the efficacy of salvage surgery for patients with recurrent nasopharyngeal carcinoma (NPC) at the primary site after radiotherapy. Retrospective analysis of 24 patients treated by transpalatal, transmaxillary, or transmandibular approach to resect the recurrent tumor, with maximum follow-up of 50 months. Academic tertiary referral center. Radiotherapy before salvage surgery included 1 to 3 courses of radiation to the nasopharynx, with doses ranging from 60 to 190 Gy. Eighteen (75%) of the patients relapsed within 2 years, and 6 (25%) relapsed more than 6 years after the last irradiation. In 4 of 6 late-relapsing cases, the histopathological type changed to keratinizing squamous cell carcinoma, which is rare in cases of NPC in Taiwan. Fourteen patients (58%) survived for 8 to 50 months after surgery (median, 18 months). The surgical complications were tolerable. Salvage surgery is feasible in selected patients with recurrent disease at the primary site. Thus, we can offer alternative retreatment in addition to external irradiation for patients with recurrent NPC.

Antibody to Epstein‐Barr virus‐specific DNase as a marker for field survey of patients with nasopharyngeal carcinoma in Taiwan

A serological survey using antibody to Epstein-Barr virus (EBV)-specific DNase activity as a marker for the identification of patients with nasopharyngeal carcinoma (NPC) has been carried out on healthy subjects who visited Government Employees' Clinic Center (GECC) for routine health examination and on individuals residing in NPC high-risk areas (HRA) in Taiwan. During a 3-year prospective study, 22,596 and 9,869 sera were collected from the GECC and HRA groups, respectively. Taking neutralization of 2 or more units of EBV DNase activity as a positive response, the positivity rates in the GECC and HRA groups were 5.4% and 11.92%, respectively. Among the antibody-positive individuals, three cases of NPC were found in the GECC group (detection rate 0.63%) and 11 in the HRA group (detection rate 1.32%). A further patient at stage III of the disease was found in the first year of following up of 1,005 antibody-positive individuals. Among the 12 NPC patients in the HRA, five were newly diagnosed as having stage II (three patients) and stage III (two patients) NPC. These results support the hypothesis that antibody against EBV-specific DNase activity may be a useful marker for detection of patients with NPC, and they imply that individuals having high levels of antibody to EBV DNase activity may have an increased risk of development of NPC.

Antibody response to Epstein-Barr-virus-specific DNase in 13 patients with nasopharyngeal carcinoma in Taiwan: a retrospective study.

Serum samples obtained from 13 individuals who were found to have a previous history of or to be suffering from nasopharyngeal carcinoma (NPC) were examined for the presence of antibody to Epstein-Barr virus (EBV) DNase activity. Significant to high levels of antibody to EBV DNase activity were detected in most serum samples obtained from four patients prior to the diagnosis of NPC. The samples from the other nine patients showed variable levels of antibody. The majority of the samples collected at the remission stage of the disease, especially those from long-term survivors, contained little or no antibody to the DNase activity. Data presented here suggest that antibody to EBV DNase activity may be a useful marker for the early diagnosis as well as the prognosis of NPC.