Nasopharyngeal brush biopsies and detection of nasopharyngeal cancer in a high-risk population

Detection of Epstein‒Barr virus DNA methylation as tumor markers of nasopharyngeal carcinoma patients in saliva, oropharyngeal swab, oral swab, and mouthwash

Saliva biopsy of nasopharyngeal carcinoma (NPC) has been developed in our latest study, indicating the application of oral sampling in NPC detection. Further exploration of the potential for self-sampling from the oral cavity is necessary. A total of 907 various samples from oral cavity, including saliva (n = 262), oropharyngeal swabs (n = 250), oral swabs (n = 210), and mouthwash (n = 185), were collected. Epstein‒Barr virus (EBV) DNA methylation at the 12,420 bp CpG site in EBV genome from the repeat-copy W promoter (Wp) region and at the 11,029 bp CpG site in the single-copy C promoter (Cp) region were simultaneously detected in these samples. A significant increase in EBV methylation, no matter at Wp or Cp region, was found in all types of samples from NPC patients. However, EBV DNA methylation in saliva and oropharyngeal swab showed a better diagnostic performance in detecting NPC. The combination of these two sample types and two markers could help to improve the detection of NPC. Our study further explored the optimal self-sampling methods and detection target in the detection of NPC and may facilitate the application of EBV DNA methylation detection in a home-based large-scale screening of NPC.

Saliva biopsy: Detecting the difference of EBV DNA methylation in the diagnosis of nasopharyngeal carcinoma

Saliva sampling is a non-invasive method, and could be performed by donors themselves. However, there are few studies reporting biomarkers in saliva in the diagnosis of NPC. A total of 987 salivary samples were used in this study. First, EBV DNA methylation was profiled by capture sequencing in the discovery cohort (n = 36). Second, a q-PCR based method was developed and five representative EBV DNA CpG sites (11 029 bp, 45 849 bp, 57 945 bp, 66 226 bp and 128 102 bp) were selected and quantified to obtain the methylated density in the validation cohort1 (n = 801). Third, a validation cohort2 (n = 108) was used to further verify the differences of EBV methylation in saliva. A significant increase of EBV methylation was found in NPC patients compared with controls. The methylated score of EBV genome obtained by capture sequencing could distinguish NPC from controls (sensitivity 90%, specificity 100%). Further, the methylated density of EBV DNA CpG sites revealed by q-PCR showed a good diagnostic performance. The sensitivity and specificity of detecting a single CpG site (11 029 bp) could reach 75.4% and 99.7% in the validation cohort1, and 78.2% and 100% in the validation cohort2. Besides, the methylated density of the CpG site was found to decrease below the COV in NPC patients after therapy, and increase above the COV after recurrence. Our study provides an appealing alternative for the non-invasive detection of NPC without clinical setting. It paves the way for conducting a home-based large-scale screening in the future.

Detection of methylation status of Epstein-Barr virus DNA C promoter in the diagnosis of nasopharyngeal carcinoma

The detection of Epstein-Barr virus (EBV) DNA load in nasopharyngeal (NP) brushing samples for diagnosis of nasopharyngeal carcinoma (NPC) has attracted great attention. Further improvements that eliminate the need for clinical settings will greatly extend its application. A total of 250 participants were recruited to obtain NP brushing samples. Brush sampling both with and without the guide of endoscopy was conducted in 38 NPC patients. EBV DNA load, EBV RNA transcript and EBV DNA C promoter methylation status were, respectively, evaluated. Typical latency II transcripts were observed in brushing samples from NPC patients but not controls. Unlike in tissues, multiple lytic gene transcripts were observed not only in NPC patients but also in controls. Apart from EBV RNA transcript, samples from NPC patients also showed higher levels of EBV DNA load and C promoter methylation degree than their controls. Qualitative analysis further showed that EBV DNA C promoter was methylated in all NPC patients but in only 18.4% of the control group. Combined analysis of EBV DNA methylated degree and EBV DNA load increased the sensitivity to 100% in the detection of NPC. Using qualitative methylated type as the criteria, up to 89.5% of samples collected via blind brushing showed consistent results with samples collected via endoscopy-guided brushing from NPC patients. Detection of the methylation status of EBV DNA C promoter in NP brushing samples shows great potential in diagnosing NPC and may provide an appealing alternative for the non-invasive detection and screening of NPC without the need for clinical settings.

Nasopharyngeal brushing: a convenient and feasible sampling method for nucleic acid-based nasopharyngeal carcinoma research

Background

Tissue specimens for nasopharyngeal carcinoma (NPC) research are scarce because of sampling difficulties. Previous studies have suggested non-invasive nasopharyngeal brushing as an effective sampling method for NPC diagnosis. The present study aimed to evaluate the feasibility of nasopharyngeal brushing in the acquisition of NPC nucleic acids for research.

Methods

Nasopharyngeal brushing samples were acquired from 24 healthy individuals and 48 NPC patients. Tissues from 48 NPC and 18 nasopharyngitis patients were collected by endoscopic biopsy. The expression levels of tumor suppressor genes (TSGs) and Epstein–Barr virus (EBV)-encoded microRNAs as well as EBV DNA copy number were measured by quantitative polymerase chain reaction in both types of samples.

Results

Among six TSGs examined, the expression levels of two genes were significantly decreased in nasopharyngeal brushing and tissue samples from NPC patients as compared with those from healthy/nasopharyngitis individuals. Four EBV-encoded microRNAs, mir-bart1-5p, mir-bart5, mir-bart6-5p, and mir-bart17-5p, were significantly up-regulated in both NPC brushing and tissue samples compared with those from healthy/nasopharyngitis controls (P < 0.001). EBV DNA was significantly increased in both nasopharyngeal brushing samples (P < 0.001) and tissue samples (P < 0.001) from NPC patients in comparison with those from healthy controls.

Conclusions

Nasopharyngeal brushing can obtain sufficient tumoral materials for the analysis of viral nucleic acid, including EBV-encoded microRNAs and EBV DNA. For the detection of TSG expression, nasopharyngeal brushings was feasible but inferior to tissue samples. This study confirms nasopharyngeal brushing as an applicable sampling method that can aid in nucleic acid-based NPC research.

Electronic supplementary material

The online version of this article (10.1186/s40880-018-0278-z) contains supplementary material, which is available to authorized users.

Progesterone analogues reduce plasma Epstein-Barr virus DNA load and improve pain control in recurrent/metastatic nasopharyngeal carcinoma patients under supportive care

BACKGROUND

Progesterone analogues, such as megestrol acetate (MA) and medroxyprogesterone (MPA), have been used for the palliative care of cancer cachexia for decades and have proven to increase body weight and improve quality of life and performance status. The objective of this study was to determine the effect of progesterone analogue use on quality of life in terms of pain control, performance status, body weight gain, and Epstein-Barr virus (EBV) DNA load in recurrent/metastatic nasopharyngeal carcinoma (NPC) patients.

METHODS

We retrospectively enrolled 41 patients with locally recurrent or metastatic NPC who received MA or MPA for cachexia management between January 2007 and February 2014. Patients who underwent aggressive treatment with intravenous chemotherapy were excluded. Body weight, performance status, pain score, and plasma EBV DNA load were used to assess quality of life before and after MA/MPA treatment.

RESULTS

Of the 41 patients, 33 patients (80.5%) experienced body weight gain after progesterone analogue intervention. A significant reduction in plasma EBV DNA load was noted after progesterone analogue use (p < 0.001). In addition, median pain and Karnofsky performance scores were also significantly improved in progesterone analogue responders compared with non-responders (4 vs. 1 and 70 vs. 80, respectively; p = 0.004 and p < 0.001, respectively).

CONCLUSION

Progesterone analogues improve quality of life in terms of performance status, pain control, and plasma EBV DNA load in patients with locally recurrent/metastatic NPC under palliative care.

Risk stratification based on change in plasma Epstein-Barr virus DNA load after treatment in nasopharyngeal carcinoma

Background: Nasopharyngeal carcinoma is associated with Epstein-Barr virus (EBV). The current study investigated change in the plasma EBV DNA load in the first 3 months after treatment and its clinical significance in NPC.

Methods: A total of 273 patients with non-metastatic, histologically-proven NPC treated with radiotherapy or chemoradiotherapy were retrospectively reviewed.

Results: EBV DNA was detectable in 19/273 (7.0%) patients at the end of therapy (end-DNA). Three months later, 16/273 (5.9%) patients had detectable EBV DNA (3-month-DNA). To investigate risk stratified by the pattern of change in post-treatment EBV-DNA, we divided patients into four subgroups: Group 1, undetectable end-DNA and 3-month-DNA (n = 244); Group 2, detectable end-DNA and undetectable 3-month-DNA (n = 13); Group 3, undetectable end-DNA and detectable 3-month-DNA (n = 7); and Group 4, detectable end-DNA and 3-month-DNA (n = 2). Patients with delayed remission of EBV DNA after treatment (Group 2) had significantly poorer 3-year DFS (48.6% vs. 89.7%, P < 0.001), DMFS (48.6% vs. 94.6%, P < 0.001) and OS (91.7% vs. 97.5%, P < 0.001) than those with persistently undetectable EBV DNA post-treatment (Group 1). Five of the seven patients with re-emergent EBV DNA (Group 3) and both patients with persistent EBV DNA post-treatment (Group 4) developed disease failure.

Conclusion: Plasma EBV DNA load continues to change during the first 3 months after treatment. The pattern of change in EBV DNA load post-treatment could help identify patients with different prognoses.

Epstein-Barr virus mir-bart1-5p detection via nasopharyngeal brush sampling is effective for diagnosing nasopharyngeal carcinoma

Epstein-Barr virus (EBV)-encoded microRNAs (miRNAs) are highly expressed in nasopharyngeal carcinoma (NPC) cases in high-risk areas, and may be involved in tumorigenesis. Using quantitative RT-PCR, we detected four EBV-encoded BamHI A rightward transcript (BART) miRNAs (mir-bart1-5p, mir-bart5, mir-bart6-5p and mir-bart17-5p) exclusively in 53 NPC biopsies as compared to 69 controls. In a larger patient group, that included 215 NPC cases and 209 controls, significantly higher levels of all four EBV miRNAs were detected in tumor cells harvested directly from the nasopharynx using a less invasive nasopharyngeal (NP) brush than in the controls (p < 0.001). One EBV miRNA, mir-bart1-5p, holds particular promise for use as a diagnostic indicator of NPC (with 93.5% sensitivity and 100% specificity), and its relative expression level was reflective of disease progression. Detection of this miRNA was effective for diagnosing early-stage NPC, even in cases that were falsely diagnosed as negative based on histopathological analysis, plasma EBV DNA load, and VCA-IgA and EA-IgA titers. EBV-encoded mir-bart1-5p detection via NP brush sampling could act as an efficient and less invasive method assisting clinical diagnosis of NPC.

Epstein-Barr virus mRNA profiles and viral DNA methylation status in nasopharyngeal brushings from nasopharyngeal carcinoma patients reflect tumor origin

Undifferentiated nasopharyngeal carcinoma (NPC) is 100% associated with Epstein-Barr virus (EBV) as oncogenic driver. NPC is often diagnosed late due to initial vague complaints and obscured location. Prior studies suggest that measurement of EBV DNA load and RNA transcripts in nasopharyngeal (NP) brushings is useful for minimally invasive NPC diagnosis. However, whether these EBV markers relate to local virus replication or reflect tumor origin remains to be demonstrated. To resolve this, we analysed EBV-DNA characteristics and quantified latent and lytic viral RNA transcripts in NP brushings and matching frozen NP-biopsy specimens from patients suspected of having NPC. We observed non-fragmented and Cp-promotor methylated EBV-DNA in both NP brushings and biopsies suggestive of tumor origin. Using quantitative RT-PCR we determined expression levels of 7 critical latent (EBER1, Qp-EBNA1, EBNA2, BART, LMP1, LMP2, BARF1) and 5 lytic (Zta, Rta, TK, PK and VCA-p18) RNA transcripts. Although latent and early lytic RNA transcripts were frequently detected in conjunction with high EBV viral load, in both brushings and biopsies the latent transcripts prevailed and reflected a typical NPC-associated latency-II transcription profile without EBNA2. Late lytic RNA transcripts were rare and detected at low levels mainly in NP brushings, suggestive of abortive viral reactivation rather than complete virus replication. EBV-IgA serology (EBNA1, VCA, Zta) did not correlate to the level of viral reactivation in situ. Overall, viral RNA profiling, DNA fragmentation and methylation analysis in NP brushings and parallel biopsies indicate that NP brush sampling provides a true and robust indicator of NPC tumor presence.

Epstein-Barr virus DNA detection in the diagnosis of nasopharyngeal carcinoma

Objectives

This study examines the presence of EpsteinBarr virus (EBV) in nasopharyngeal carcinoma (NPC) by using polymerase chain reaction (PCR)

Study Design

Eighty-six postnasal biopsy samples and 71 fine-needle aspirate samples of neck masses were obtained from patients who were clinically suspect for NPC. Genomic DNA was extracted from the samples, and EBNA1, EBNA2, and LMP genes of EBV were detected by PCR. PCR results were compared with NPC histopathology findings.

Results

The sensitivity of PCR to detect EBNA1 (97.14%), EBNA2 (88.57%), and LMP (91.43%) genes of EBV in nasopharyngeal biopsy samples were higher than those in fine-needle aspirate samples.

Conclusion

Detection of EBV by PCR in tissue obtained from nasopharyngeal biopsy and fine-needle aspirate samples of neck masses is a relatively inexpensive, reliable, and accurate method of diagnosing NPC. Detection of EBV genes is on par with histopathological examination (HPE) and superior to fine-needle aspirate cytology.

Significance

PCR is an ideal tool for suggesting NPC and guiding the diagnostic workup in occult primary tumors, facilitating earlier diagnosis and reducing morbidity and mortality. © 2007 American Academy of Otolaryngology-Head and Neck Surgery Foundation. All rights reserved.

Evaluation of Risk Factors for Nasopharyngeal Carcinoma in a High-risk Area of India, the Northeastern Region

Northeastern India is a major nasopharyngeal carcinoma (NPC) high risk-area although the rest of the country has very low incidence. A case-control study of 105 NPC cases and 115 controls was conducted to identify the potential risk factors for NPC development in this region. Information was collected by interviewer about socio-demographic characteristics, cigarette smoking, alcohol consumption, dietary history, occupational history, and a family history of cancer. Epstein-Barr viral load was assayed from the blood DNA by real time PCR. Associations between GSTs genotypes, cytochrome P450 family including CYP1A1, CYP2E1 and CYP2A6 polymorphisms and susceptibility to relationship between the diseases were studied using PCR-RFLP assay. Results indicate that Epstein-Barr virus load was significantly higher in patients compared to controls (p<0.0001). Furthermore, concentration of blood EBV-DNA was significantly higher in advanced stage disease (Stage III and IV) than in early stage disease (Stage I and II) (p<0.05). Presence of CYP2A6 variants that reduced the enzyme activity was significantly less frequent in cases than controls. Smoked meat consumption, exposure to smoke, living in poorly ventilated house and alcohol consumption were associated with NPC development among the population of Northeastern India. Thus, overall our study revealed that EBV viral load and genetic polymorphism of CYP2A6 along with living practices which include smoked meat consumption, exposure to smoke, living in poorly ventilated houses and alcohol consumption are the potential risk factors of NPC in north eastern region of India. Understanding of the risk factors and their role in the etiology of NPC are helpful forpreventive measures and screening.

Quantification of Epstein-Barr virus DNA load in nasopharyngeal brushing samples in the diagnosis of nasopharyngeal carcinoma in southern China

Nasopharyngeal carcinoma (NPC) is highly incident in southern China, where 40% of world's new cases arise each year. Detection of Epstein–Barr virus (EBV) DNA load in nasopharyngeal (NP) brush/swab samples has gradually been established as a method for diagnosis of NPC. However, its applicable value in NPC diagnosis has never been investigated in southern China. It is important to explore whether such a test could be applicable to our local population. A total of 245 consecutive participants undergoing NP brushing examination were recruited to obtain the NP brushing samples in this study. Quantitative PCR assays were used to obtain the EBV DNA load. Mann–Whitney, ANOVA and receiver operating characteristic tests were used to analyze its diagnostic value. NP brushing samples from NPC patients showed extremely high levels of EBV DNA load (mean = 46360 copy/ng DNA) compared to its expression from non-NPC control (mean = 28 copy/ng DNA) and high-risk control (mean = 50 copy/ng DNA) groups. It produced 96% sensitivity and 97% specificity, at the COV = 225 copy/ng DNA. Furthermore, EBV DNA load could reflect disease progress. Our data showed a better performance of EBV DNA load in NP brushing samples compared with an initial biopsy, immunoglobulin A (IgA) antibody titers to viral capsid antigen in serum and EBV DNA load in plasma. Detection of EBV DNA load in NP brushing samples could be an effective supplement for NPC diagnosis. Being minimally invasive and low cost, NP brush sampling combined with EBV DNA detection demonstrates great potential for screening high-risk populations for NPC.

Trans-Oral Brush Biopsies and Quantitative PCR for EBV DNA Detection and Screening of Nasopharyngeal Carcinoma

Objectives

To evaluate a newly developed noninvasive ambulatory, quantitative polymerase chain reaction (Q-PCR) Epstein-Barr virus (EBV) DNA detection and screening system (NP Screen™) for nasopharyngeal carcinoma (NPC).

Study Design

Correlation of the nasopharyngeal epithelial EBV-DNA levels and clinical findings by nasopharyngoscopy and final pathologic diagnosis of NPC with biopsy.

Setting

Multicenter ENT/Oncology clinics in Hong Kong (Radiation Oncology Clinic at the Queen Elizabeth Hospital and Radiation Oncology Clinic and Head and Neck Clinic, Queen Mary Hospital, University of Hong Kong) and in Toronto, Canada (the Otolaryngology-Head and Neck Clinic at the Rouge Valley Health System and 2 large ENT practices in Toronto).

Methods

A single-use trans-oral brush was used for rapid, nontraumatic nasopharyngeal (NP) epithelial cells DNA harvest in 600 Chinese patients, combined with a preservation and shipping kit for remote, real-time Q-PCR EBV DNA determinations.

Results

All 600 patients had NP brushings using NP Screen in an ambulatory environment, and no adverse events or complications were recorded. A final 578 patients were included with sufficient amount of DNA for completion of the Q-PCR assay. Of these 578 patients, 94 were confirmed positive for NPC histologically. The study yielded a sensitivity of 98.9%, specificity of 99.3%, positive predictive value (PPV) of 96.9%, and negative predictive value (NPP) of 99.7% for NP Screen in detecting NPC. Endoscopy had a sensitivity of 94%, specificity 97.1%, PPV 85%, and NPP 98.9%.

Conclusions

The trans-oral brushing system fulfills the characteristics of a noninvasive, sensitive, specific detection method suitable for routine, large-scale ambulatory NPC risk assessment for high-risk NPC populations.

Primary treatment results of Nasopharyngeal Carcinoma (NPC) in Yogyakarta, Indonesia

Introduction

Nasopharyngeal Carcinoma (NPC) is a major health problem in southern and eastern Asia. In Indonesia NPC is the most frequent cancer in the head and neck area. NPC is very sensitive to radiotherapy resulting in 3-year disease-free and overall survival of approximately 70% and 80%, respectively. Here we present routine treatment results in a prospective study on NPC in a top referral; university hospital in Indonesia.

Methods

All NPC patients presenting from September 2008 till January 2011 at the ear, nose and throat (ENT) department of the Dr. Sardjito General Hospital, Universitas Gadjah Mada, Yogyakarta, Indonesia, were possible candidates. Patients were included if the biopsy was a histological proven NPC without distant metastasis and were assessed during counselling sessions prior to treatment, as being able to complete the entire treatment.

Results

In total 78 patients were included for treatment analysis. The median time between diagnosis and start of radiotherapy is 120 days. Forty-eight (62%) patients eventually finished all fractions of radiotherapy. The median duration of the radiotherapy is 62 days for 66 Gy. Median overall survival is 21 months (95% CI 18–35) from day of diagnosis.

Conclusion

The results presented here reveal that currently the treatment of NPC at an Indonesian hospital is not sufficient and cannot be compared to the treatment results in literature. Main reasons for these poor treatment results are (1) a long waiting time prior to the start of radiotherapy, (2) the extended overall duration of radiotherapy and (3) the advanced stage of disease at presentation.

Epstein-Barr virus DNA load in nasopharyngeal brushings and whole blood in nasopharyngeal carcinoma patients before and after treatment

PURPOSE

Nasopharyngeal carcinoma (NPC) is consistently associated with Epstein-Barr virus (EBV) and highly prevalent in Indonesia. EBV-DNA load can be used for early diagnosis and may have prognostic value. In this study, EBV-DNA load was evaluated in minimal invasive nasopharyngeal (NP) brushings and whole blood for initial diagnosis and therapy assessment against the standard-of-care diagnosis by biopsy with EBV-RISH and standard EBV-IgA serology.

EXPERIMENTAL DESIGN

NP brushings and blood samples were collected from 289 consecutive ENT patients suspected of NPCs and 53 local healthy controls. EBV-DNA load was quantified by real-time PCR and serology by peptide-based EBV-IgA ELISA. Tissue biopsies were examined by routine histochemistry and by EBER RNA in situ hybridization.

RESULTS

Repeated NP brushing was well tolerated by patients and revealed high viral load in the 228 NPC cases at diagnosis than 61 non-NPC cancer cases and healthy controls (P < 0.001). The diagnostic value of EBV-DNA load in blood and EBV-IgA serology was inferior to the NP brush results. The level of EBV-DNA load in brushes of patients with NPC was not related to T, N, or M stage, whereas elevated EBV-DNA load in blood correlated with N and M stage. EBV-DNA levels in brushings and whole blood showed a significant reduction at 2 months after treatment (P = 0.001 and P = 0.005, respectively), which was not reflected in EBV-IgA serology.

CONCLUSIONS

NP brush sampling combined with EBV-DNA load analysis is a minimal invasive and well-tolerated diagnostic procedure, suited for initial diagnosis and follow-up monitoring of NPCs.

Expression profile of latent and lytic transcripts of epstein-barr virus in patients with gastroduodenal diseases: a study from northern India

Epstein-Barr virus (EBV) has been shown to be associated with gastric cancer. However, inconsistent findings have been reported regarding the EBV reactivation in gastric cancer and non-carcinomatous gastric epithelium. Therefore, the aim of the study was to investigate the effect of clinicopathological findings on the expression of different transcripts of EBV in patients with gastric cancer, peptic ulcer, and dyspepsia. A total of 200 adult patients (dyspepsia [120], peptic ulcer [30], gastric cancer [50]) undergoing upper gastrointestinal endoscopy were enrolled. EBV infection was diagnosed with non-polymorphic Epstein-Barr nuclear antigen1 (EBNA1) gene based PCR and confirmed by real-time PCR. The transcripts of EBV were detected by real-time RT-PCR. In patients with gastric cancer and peptic ulcer, EBV DNA was detected more often than in those with dyspepsia (P < 0.05). EBNA1 transcript was detected in all EBV positive cases and its expression was neither associated with disease nor with histopathological findings. The expression of BZLF1 was significantly associated with gastric cancer and peptic ulcer compared to dyspepsia (P < 0.01). BZLF1 expression was also found to be higher in Helicobacter pylori infected patients (P = 0.058). Expression of BARF1 and BcLF1 were significantly higher in gastric epithelium of patients having severe grade chronic inflammation (P = 0.05) and gastric atrophy (P = 0.02), respectively. In conclusion, increased expression of lytic transcripts in patients with gastric cancer, peptic ulcer, gastric atrophy, chronic inflammation and H. pylori infection suggests the association of these factors with EBV reactivation.

Short-term effect of different teaching methods on nasopharyngeal carcinoma for general practitioners in Jakarta, Indonesia

In Indonesia, Nasopharyngeal Carcinoma (NPC) is the most frequent cancer of the head and neck region. At first presentation in the hospital most patients already have advanced NPC. Our previous study showed that general practitioners (GPs) working in Yogyakarta, Indonesia lack the knowledge necessary for early detection of NPC. By providing training on early symptoms of NPC we hope that the diagnosis and referral will occur at an earlier stage. Here we assess the current NPC knowledge levels of GPs in Jakarta, evaluate improvement after training, compare the effectiveness of two training formats, and estimate the loss of recall over a two week period.

Serologic Antienzyme Rate of Epstein-Barr Virus DNase-Specific Neutralizing Antibody Segregates TNM Classification in Nasopharyngeal Carcinoma

Purpose

We investigate the value of pretreatment serologic antienzyme rate (AER) of Epstein-Barr virus (EBV) DNase-specific neutralizing antibody complementing TNM staging in prognostication of nasopharyngeal carcinoma (NPC).

Patients and Methods

Pretreatment serum samples from 1,303 patients with untreated NPC were collected and examined for AER. After a 10-year follow-up period, the prognoses of the patients, classified by their clinical stage with AER, were assessed by multivariate analysis. Of the 1,303 patients, 600 patients were randomly assigned to a training set to generate an AER cutoff point by receiver operating characteristic (ROC) curve analysis. AER levels were then analyzed with overall survival (OS), progression-free survival (PFS), local failure–free survival (LFFS), and distant metastasis–free survival (DMFS) in a testing set (703 patients). Another independent cohort of 464 patients was studied in a validating set.

Results

In the training set, the ROC analysis–generated AER cutoff point for OS was 58.0%, which was used as the cutoff point in the testing set. The subset of low AER levels predicted a significant survival advantage over the subset of high AER levels for OS, PFS, LFFS, and DMFS in the testing set. Moreover, two distinguished subgroups were segregated by an AER level of 58.0% within each clinical stage comparing prognostication of OS, PFS, LFFS, and DMFS. Importantly, AER level was revealed as the only significant independent prognostic factor for death, recurrence, and distant metastasis in the validating set.

Conclusion

Pretreatment serologic AER of EBV DNase-specific neutralizing antibody serves as an independent prognostic marker complementing TNM stage in NPC. Supplementing pretreatment AER with TNM staging leads to more accurate risk definition in patient subgroups.

Use of combined molecular biomarkers for prediction of clinical outcomes in locally advanced tonsillar cancers treated with chemoradiotherapy alone

BACKGROUND

Environmental exposures to tobacco, alcohol, human papillomavirus (HPV) and/or Epstein-Barr virus (EBV), all of which can perturb multiple cell cycle proteins or tumor suppressors, have been implicated in the pathogenesis of different subsets of head and neck cancers. The aim of this study was to investigate to which extent the virus infection by itself, and/or the altered cell cycle proteins, contributes to prognosis in locally advanced tonsillar squamous cell carcinomas (TSCCs) treated with concurrent chemoradiotherapy (CCRT) alone.

METHODS

Serial tumor tissue arrays from archival samples were tested for the presence of HPV genome integration or EBV episome by means of DNA sequencing, real-time polymerase chain reaction (PCR), and in situ hybridization. Alterations of cell cycle proteins (p53, pRb, and p21) were evaluated by immunohistochemical staining. The association of viral presence with altered cell cycle proteins was correlated to clinical outcomes.

RESULTS

Of the 46 patients with the same T2N2bM0 stage IVA among consecutive patients with TSCC, 23 (50%) had integrated HPV DNA and only 1 (2%) had EBV episome. The HPV types detected were almost all HPV-16. A reduced expression pattern of p53, pRb, and p21 was noted in HPV-positive tumors, and the incremental number of alterations in the 3 proteins was significantly associated with HPV-negative tumors. The presence or absence of HPV together with the number of altered expression of the 3 cell cycle markers resulted in further identification of 4 biologically and clinically distinct subgroups with different outcomes after CCRT.

CONCLUSIONS

Use of combined biomarkers of oncogenic HPV and tumor suppressors of p53, pRb, and p21 in advanced TSCC provides prognostic molecular classification superior to the TNM stage system and identifies low-risk patients for organ preservation by CCRT alone and high-risk patients who might benefit from planned tonsillectomy and neck dissection before or after CCRT.

Association of Helicobacter pylori and Epstein-Barr virus with gastric cancer and peptic ulcer disease

OBJECTIVE

Helicobacter pylori and Epstein-Barr virus (EBV) infections are common world-wide. Though H. pylori infection is a major factor in gastroduodenal diseases, its role in association with EBV infection is unknown. We prospectively studied the association of H. pylori and EBV in patients with gastric cancer (GC) and peptic ulcer disease (PUD).

MATERIAL AND METHODS

A total of 348 adult patients (non-ulcer dyspepsia (NUD) 241, PUD 45, GC 62) undergoing upper gastrointestinal endoscopy between September 2003 and May 2007 were enrolled in the study. H. pylori infection was diagnosed by rapid urease test, culture, histopathology and polymerase chain reaction (PCR). EBV DNA was detected by non-polymorphic Epstein-Barr nuclear antigen-1 (EBNA-1) gene-based PCR and sequence analysis.

RESULTS

The rate of H. pylori infection was higher in patients with PUD than in those with GC (80% versus 56.5%, p=0.01) and NUD (80% versus 55.2%, p=0.002). In patients with GC and PUD, EBV DNA was detected more often than in those with NUD (GC versus NUD - 82.3% versus 37.3%, p<0.001; PUD versus NUD - 75.5% versus 37.3%, p<0.001). H. pylori infection and EBV DNA detected in different groups of patients was as follows: 62.2% in PUD, 46.8% in GC and 29.5% in NUD. PUD and GC were significantly associated (p<0.001 and <0.05, respectively) with the presence of H. pylori infection and EBV DNA as compared with NUD.

CONCLUSIONS

EBV DNA either alone or in combination with H. pylori infection was significantly associated with GC and PUD, suggesting that EBV might play an important role in gastroduodenal pathology.

Update on molecular diagnostic tests in head and neck cancer

Head and neck cancers (HNCs) include several cancers originating in the upper airways that represent a variety of histologies. The most common type of HNC is squamous cell carcinoma (SCC), which is linked to tobacco and alcohol use and to human papilloma virus (HPV). At present, there are no standard molecular tests that are routinely used in clinics. This overview will discuss the current knowledge on molecular markers with the potential to be developed as diagnostic tests for cancer risk assessment, early detection, clinical response prediction to specific therapies, and prognosis. These markers are usually based on recent findings in tumor biology and genetic defects in HNC, and provide information both independently and in combination with currently available clinical parameters. In practice, many potential markers are difficult to measure due to assay variability, lack of standards for the interpretation of assay results, and incomplete knowledge of the effects on disease biology and response to treatment. However, there is great enthusiasm for the general concept of using molecular knowledge for the clinical management of HNC. Although it will be a great challenge to develop robust and reliable molecular diagnostic tests, the development of promising assays fueled by advances in science and technology will continue and will ultimately reach the goal of improving the care of HNC patients.

Nasopharyngeal carcinoma: molecular pathogenesis and therapeutic developments

Nasopharyngeal carcinoma (NPC) is a prevalent tumour in southern China and southeast Asia, particularly in the Cantonese population, where its incidence has remained high for decades. Recent studies have demonstrated that the aetiology of NPC is complex, involving multiple factors including genetic susceptibility, infection with the Epstein-Barr virus (EBV) and exposure to chemical carcinogens. During development of the disease, viral infection and multiple somatic genetic and epigenetic changes synergistically disrupt normal cell function, thus contributing to NPC pathogenesis. NPC is highly radiosensitive and chemosensitive, but treatment of patients with locoregionally advanced disease remains problematic. New biomarkers for NPC, including EBV DNA copy number or methylation of multiple tumour suppressor genes, which can be detected in serum and nasopharyngeal brushings, have been developed for the molecular diagnosis of this tumour. Meanwhile, new therapeutic strategies such as intensity-modulated radiation therapy and immuno- and epigenetic therapies might lead to more specific and effective treatments.

Noninvasive diagnosis of nasopharyngeal carcinoma: nasopharyngeal brushings reveal high Epstein-Barr virus DNA load and carcinoma-specific viral BARF1 mRNA

Nasopharyngeal carcinoma (NPC) is the most prevalent ENT-tumour in Indonesia. We investigated the primary diagnostic value of Epstein-Barr virus (EBV) DNA load and mRNA detection in noninvasive nasopharyngeal (NP) brushings, obtained prospectively from consecutive Indonesian ENT-patients with suspected NPC (N=106) and controls. A subsequent routine NP biopsy was taken for pathological examination and EBER-RISH, yielding 85 confirmed NPC and 21 non-NPC tumour patients. EBV DNA and human DNA load were quantified by real-time PCR. NP brushings from NPC patients contained extremely high EBV DNA loads compared to the 88 non-NPC controls (p<0.0001). Using mean EBV DNA load in controls plus 3 SD as cut-off value, specificity, sensitivity, positive and negative predictive values were 98, 90, 97 and 91%, respectively. Epstein-Barr nuclear antigen 1 (EBNA1) and the carcinoma-specific BARF1 mRNA were detected by nucleic acid sequence based amplification and found in 86 and 74% of NP brushings, confirming NPC tumour cell presence. EBV RNA positivity was even higher in fresh samples stored at -80 degrees C until RNA expression analyses (88% for both EBNA1 and BARF1). EBV RNA-negative NP brushings from proven NPC cases had the lowest EBV DNA loads, indicating erroneous sampling. No EBV mRNA was detected in NP brushings from healthy donors and non-NPC patients. In conclusion, EBV DNA load measurement combined with detection of BARF1 mRNA in simple NP brushings allows noninvasive NPC diagnosis. It reflects carcinoma-specific EBV involvement at the anatomical site of tumour development and reduces the need for invasive biopsies. This procedure may be useful for confirmatory diagnosis in large serological NPC screening programs and has potential as prognostic tool.

Epstein–Barr virus: the future for screening, treatment and monitoring of nasopharyngeal carcinoma

Nasopharyngeal carcinoma (NPC) is often not diagnosed until an advanced stage of the disease, and has a poor 5-year survival with current therapies. Thus, screening programs to identify high-risk patients at early disease stages are essential to improve patient outcomes, most likely through using Epstein–Barr virus (EBV) DNA monitoring in conjunction with tumor-specific markers. EBV-specific cytotoxic T lymphocytes (CTLs) have been utilized successfully for long-term regression of EBV-associated B-cell lymphomas, such as post-transplant lymphoproliferative disease. This strategy has recently been adapted to raise latent membrane proteins 1 and 2, and EBV nuclear antigen 1-specific CD8+ and CD4+ T cells to target EBV proteins expressed in NPC tumors. Future challenges will be focused on developing multiple-target therapies, including improving CTL persistence and tumor specificity. Understanding the role of EBV infection and protein expression in NPC will be pivotal in the development of screening protocols and novel treatments, including vaccines.

Molecular diagnosis of nasopharyngeal carcinoma: detecting LMP-1 and EBNA by nasopharyngeal swab

OBJECTIVES

The aim of this study was to investigate the feasibility of molecular diagnosis of nasopharyngeal carcinoma (NPC) by combining nasopharyngeal swab and polymerase chain reaction (PCR) to detect Epstein-Barr virus (EBV) derived latent membrane protein-1 gene (LMP-1) and Epstein-Barr nuclear antigen gene (EBNA).

METHODS

437 adults underwent nasopharyngoscopy, possible biopsy, and nasopharyngeal swab to obtain nasopharyngeal cells for the detection of LMP-1 and EBNA by PCR.

RESULTS

By detecting LMP-1 and EBNA in the nasopharyngeal swabs, NPC could be diagnosed with a false-positive rate of 1.7% (6/354), a false-negative rate of 8.6% (6/70), a sensitivity of 91.4% (64/70), a specificity of 98.3% (348/354), positive predictive value of 91.4% (64/70), and negative predictive value of 98.3% (348/354).

CONCLUSION

Detecting EBV genomic LMP-1 and EBNA by nasopharyngeal swab verifies NPC with a sensitivity of 91.4% and specificity of 98.3%. The nasopharyngeal swab coupled with PCR based EBV LMP-1 and EBNA detection could serve as a good supplement to pathological diagnosis of NPC.

Prevalence of LMP-1 gene in tonsils and non-neoplastic nasopharynxes by nest-polymerase chain reaction in Taiwan

BACKGROUND

The purpose of this study was to investigate the frequency of Epstein-Barr virus (EBV) latent membrane protein-1 (LMP-1) in tonsils and non-neoplastic nasopharynxes in Taiwan.

METHODS

Nest-polymerase chain reaction (nest-PCR) was used to examine the presence of LMP-1 gene in lymphoid hyperplasia from non-neoplastic tonsillar and nasopharyngeal tissues and in tonsillar cancers.

RESULTS

In 152 cases, 64 biopsy tissues were obtained from lymphoid hyperplasia of nasopharynxes, 57 from tonsillectomy of non-neoplastic tonsils, and 31 from tonsillar cancers. LMP-1 was detected in 43.4% of the study group. Nineteen (29.7%) and 29 (50.9%) lymphoid hyperplasias from normal nasopharynxes and tonsils, respectively, and 18 (58.1%) biopsies from tonsillar cancers had positive LMP-1. The 30-base pair (bp) deleted variant was detected in 89.5% and 82.8% of normal nasopharynxes and tonsils, respectively, and in 66.7% of biopsies from tonsillar cancers (p =.198).

CONCLUSION

This study found that the 30-bp variant was the predominant type of LMP-1 from a healthy population in Taiwan.

Serum EBV DNA as a Biomarker in Primary Nasopharyngeal Carcinoma of Indian Origin

BACKGROUND

Nasopharyngeal carcinoma (NPC) is a unique tumor due to its etiology and endemic distribution. Ethnic and regional factors are found to strongly influence the risk of disease; however, there have been no well-conducted studies on Indian patients. The present study assesses the relationship between Epstein-Barr Virus (EBV) and sporadic Indian NPC and the role of serum EBV DNA in NPC detection.

METHODS

Primers directed against non-polymorphic Epstein-Barr nuclear antigen-1 (EBNA-1) gene were used to detect the presence of EBV DNA from fresh tissue and serum in NPC, using PCR.

RESULTS

EBV DNA was detected in 69% of the biopsies and 58% of the serum of the NPC patients. With respect to histology, WHO Type III NPC, WHO Type II tumors and WHO I tumors showed 100%, 72.2% and 33% EBV positivity, respectively. EBV positivity was also observed in 23% (6/26) of benign samples. All biopsies of patients with positive serum samples were positive for EBV DNA.

CONCLUSION

EBV infection was found in sporadic NPC of South Indian origin, which confirms the etiological role of EBV in NPC. Detection of EBNA-1 in the serum and corresponding tissues of NPC patients suggests that the serum EBV DNA originates from NPC and also indicates the benefit of circulating viral DNA as an early marker in the diagnosis of NPC. Serum DNA-PCR methods can be extrapolated to follow-up studies involving tumor regression or to assess the response to various therapies.

Phase II study of neoadjuvant carboplatin and paclitaxel followed by radiotherapy and concurrent cisplatin in patients with locoregionally advanced nasopharyngeal carcinoma: therapeutic monitoring with plasma Epstein-Barr virus DNA

PURPOSE

To assess the efficacy of neoadjuvant paclitaxel and carboplatin (TC) followed by concurrent cisplatin and radiotherapy (RT) in patients with locoregionally advanced nasopharyngeal carcinoma (NPC) and to monitor treatment response with plasma Epstein-Barr virus (EBV) DNA.

PATIENTS AND METHODS

Thirty-one patients with International Union Against Cancer stages III and IV undifferentiated NPC had two cycles of paclitaxel (70 mg/m2 on days 1, 8, and 15) and carboplatin (area under the curve 6 mg/mL/min on day 1) on a 3-weekly cycle, followed by 6 to 8 weeks of cisplatin (40 mg/m2 weekly) and RT at 66 Gy in 2-Gy fractions. Plasma EBV DNA was measured serially using the real-time quantitative polymerase chain reaction method. Results All patients completed planned treatment. Response to neoadjuvant TC was as follows: 12 patients (39%) achieved partial response (PR) and 18 achieved (58%) complete response (CR) in regional nodes; five patients (16%) achieved PR and no patients achieved CR in nasopharynx. At 6 weeks after RT, one patient (3%) achieved PR and 30 patients (97%) achieved CR in regional nodes, and 31 patients (100%) achieved CR in nasopharynx; 29 patients (93%) had EBV DNA level of less than 500 copies/mL. Neoadjuvant TC was well tolerated, and the most common acute toxicity of cisplatin plus RT was grade 3 mucositis (55%). At median follow-up of 33.7 months (range, 7 to 39.3 months), six distant and three locoregional failures occurred. Plasma EBV DNA level increased significantly in eight of nine patients who experienced treatment failure but did not increase in those who did not. The 2-year overall and progression-free survival rates were 91.8% and 78.5%, respectively. CONCLUSION This strategy was feasible and resulted in excellent local tumor control. Serial plasma EBV DNA provides a noninvasive method of monitoring response in NPC.

Improved Accuracy of Detection of Nasopharyngeal Carcinoma by Combined Application of Circulating Epstein–Barr Virus DNA and Anti-Epstein–Barr Viral Capsid Antigen IgA Antibody

Background: Circulating Epstein–Barr viral (EBV) DNA and anti-EBV capsid antigen IgA (IgA VCA) represent two of the most sensitive peripheral blood markers of nasopharyngeal carcinoma (NPC), but direct comparative studies of these two markers are lacking.

Methods: The sensitivities and specificities of IgA-VCA and EBV DNA for diagnosis of NPC were determined in 139 new cases of NPC and 178 healthy individuals, respectively. EBV DNA was also assessed in 36 healthy family members identified as having false-positive IgA-VCA results at a screening clinic. EBV DNA was measured by a real-time quantitative PCR assay with a detection limit of 60 copies/mL. IgA-VCA was measured by semiquantitative indirect immunofluorescent method; a titer ≥1/10 was taken as positive.

Results: The sensitivities of EBV DNA and IgA-VCA for diagnosis of NPC were 95% (95% confidence interval, 91–98%) and 81% (73–87%), respectively. The combined marker panel had an overall sensitivity (positive result by either marker) of 99%. The concentrations of both markers showed dependence on cancer stage. The specificities of EBV DNA and IgA-VCA were 98% (96–99%) and 96% (91–98%), respectively. Among 36 healthy family members with false-positive IgA-VCA results, three-fourths had undetectable EBV DNA, whereas the others had increased EBV DNA concentrations that were significantly lower than in NPC patients.

Conclusions: For diagnosis of NPC, EBV DNA identifies almost all false-negative IgA-VCA cases and gives a 99% diagnostic sensitivity when combined with IgA-VCA. In the screening setting, EBV DNA identifies three-fourths of false-positive IgA-VCA cases. The selective application of EBV DNA in an IgA-VCA-based screening protocol could improve screening accuracy with only moderate increases in cost.

Presence of the latent membrane protein 1 gene in nasopharyngeal swabs from patients with mucosal recurrent nasopharyngeal carcinoma

BACKGROUND

Nasopharyngeal carcinoma (NPC) is the most common head and neck malignancy in southeastern China and Taiwan. Early detection of the local disease followed by timely and appropriate treatment is essential to increasing cure and survival rates. Detection of Epstein-Barr virus (EBV) genomic DNA, such as the latent membrane protein 1 gene (LMP-1), in patients postirradiation during follow-up may indicate mucosal recurrence.

METHODS

Seventy-one patients with NPC underwent serial nasopharyngeal swabs for LMP-1 polymerase chain reaction assay before, during, and after irradiation. All of patients achieved a complete disease remission of the LMP-1 gene after irradiation that lasted for at least 6 months.

RESULTS

The median LMP-1 disease remission time after the beginning of irradiation was 4.3 weeks. Patients with early LMP-1 disease remission (</= 4 weeks after the beginning of irradiation) and delayed LMP-1 disease remission (> 4 weeks) had 3-year local control rates of 93.5% and 76.9%, respectively (P = 0.0529). The LMP-1 gene was detected again (reexpression of LMP-1 [re-LMP-1]) in 10 patients after irradiation with at least 6 months of follow-up. Nine of 10 patients (90%) in the re-LMP-1 positive group and 2 of 61 patients (3.3%) in the re-LMP-1 negative group developed local recurrence. Mucosal recurrence developed in nine patients, and all displayed re-LMP-1. By detecting re-LMP-1 using nasopharyngeal swabs, mucosal recurrence was diagnosed with a sensitivity of 100% (9 of 9 patients) and a specificity of 98.4% (61 of 62 patients). The 3-year overall survival rate, the disease free survival rate for the entire group, and the estimated local mucosal control rates in the re-LMP-1 positive and re-LMP-1 negative groups were 86.5%, 76.5%, 19.4%, and 96.7%, respectively.

CONCLUSIONS

Expression of EBV LMP-1 in nasopharyngeal swab specimens from patients with irradiated/treated NPC can provide a highly sensitive and specific method of forecasting mucosal recurrence. This investigation confirmed the reliability and feasibility of nasopharyngeal swabs in screening for mucosal recurrences in patients with NPC.

The p53 codon 72 polymorphism in Thai nasopharyngeal carcinoma

Nasopharyngeal carcinoma (NPC) is a serious cancer in Thailand. To address on the genetic risk factor for NPC, we investigated association between the p53 codon 72 polymorphism (Pro/Arg) and NPC susceptibility in the Thai. The genotype frequency of this polymorphism in 102 NPC patients and 148 age-matched healthy controls was determined by using a PCR-RFLP assay. No statistically significant difference in the overall genotype frequencies or allele frequencies between cases and controls was observed. Among NPC patients, no statistical significant difference in p53 genotype frequencies between sex, histological types and clinical stages was observed. When cases and controls were categorized into 3 groups of age, >40, >45 and >50 years, the frequencies of p53 genotype in the cases were significantly different from those of the controls (P<0.05). The p53 Pro homozygotes with age of >40 years had twofold to threefold higher risk to develop NPC and the risk was increased with age (Odds Ratio (OR) increased from 2.01 to 2.63 by age >40 to >50 years). Individuals of age >40, >45 and >50 years with an Arg/Arg genotype and of age >45 and >50 years with combined Arg/Arg or Arg/Pro genotype had lower risk to develop NPC than those with Pro/Pro genotype (P<0.05). Collectively, we suggest that the p53 gene polymorphism may associate with NPC susceptibility in Thai population, particularly the Pro/Pro genotype carriers with age of >40 years. The detection of this p53 polymorphism may be a useful tool for screening of early stage and diagnosis of NPC.

Detection of Epstein-Barr virus-derived latent membrane protein-1 gene in various head and neck cancers: is it specific for nasopharyngeal carcinoma?

OBJECTIVE

The object of the study was to determine the incidence of the presence of Epstein-Barr virus-derived latent membrane protein-1 (LMP-1) gene in various head and neck cancers by polymerase chain reaction method.

STUDY DESIGN

Prospective study.

METHODS

During a 5-year period, polymerase chain reaction was used to investigate the presence of LMP-1 gene in various head and neck cancers from different locations and histopathological types, noncancerous nasopharyngeal biopsy samples, and tonsillectomy specimens from patients with chronic hypertrophic tonsillitis.

RESULTS

Of 202 patients enrolled in the study, 53 were diagnosed by pathological study with oropharyngeal carcinoma, 45 with nasopharyngeal carcinoma, 26 with oral cavity carcinoma, 26 with laryngohypopharyngeal carcinoma, 31 with nasopharyngeal lymphoid hyperplasia, and 21 with tonsils with lymphoid hyperplasia. After the application of polymerase chain reaction, the LMP-1 gene was not detected in any sample from oral cavity carcinoma, laryngohypopharyngeal carcinoma, or nasopharyngeal lymphoid hyperplasia or from tonsillectomy specimens but was detected in only one case of tonsillar carcinoma. On the contrary, the LMP-1 gene was detected in 43 (95.6%) of 45 samples from patients with nasopharyngeal carcinoma. The statistical analysis shows a significant association (P <.001) between the presence of LMP-1 gene and tumor localization in the nasopharynx.

CONCLUSIONS

The study shows that the presence of LMP-1 gene detected by polymerase chain reaction in the tumor cell is only significantly associated with tumor located in the nasopharynx, implying that Epstein-Barr virus plays a trifling role in the tumorigenesis of carcinomas arising from other head and neck locations. The polymerase chain reaction method that was used is a potential tool for screening nasopharyngeal carcinoma.

The usefulness of cytodiagnosis and DNA cytometry on nasopharyngeal brush smears for the diagnosis of nasopharyngeal carcinoma

BACKGROUND

To assess the usefulness of combining cytodiagnosis and DNA cytometry on nasopharyngeal brush samples for the detection of nasopharyngeal carcinoma (NPC).

METHODS

DNA ploidy analysis was undertaken on 66 nasopharyngeal brush samples that had been previously evaluated cytologically.

RESULTS

Cytodiagnosis and ploidy analysis demonstrated a sensitivity of 66% and 55%, respectively. Both techniques had a specificity of 100% for NPC cases that were histologically confirmed. The negative predictive values for cytodiagnosis and ploidy analysis were 29% and 24%, respectively.

CONCLUSIONS

The sensitivity and specificity for cytodiagnosis were not improved by the addition of DNA ploidy analysis. Furthermore, combining the two techniques did not confer any significant advantage compared with the use of cytology and DNA ploidy alone. The relatively low negative predictive values are a significant limitation, and combining cytodiagnosis and ploidy analysis on nasopharyngeal brush samples cannot be recommended for the detection of NPC.

The use of brush cytology and directed biopsies for the detection of nasopharyngeal carcinoma and precursor lesions

BACKGROUND

It has been proposed that nasopharyngeal carcinoma (NPC) has an early noninvasive stage, designated nasopharyngeal intraepithelial neoplasia (NPIN). Hence, the detection and treatment of NPIN will prevent NPC from developing, and this would be similar to the strategies used for cervical cancer prevention. We wanted to ascertain the feasibility of using a brush sampler to collect cells for the cytologic diagnosis of NPIN and NPC. If successful, the technique could be used as a screening test in endemic areas.

METHODS

A disposable sampler (Uterobrush) was used to collect nasopharyngeal mucosal brushings from 546 patients for cytologic examination. After this, most patients had biopsies, and this allowed histologic-cytologic correlation to be undertaken.

RESULTS

In 528 patients (96.7%) there were satisfactory cytologic and biopsy specimens for evaluation. There were 149 cases with positive histology and 103 had positive cytology (specificity was 100% and the sensitivity was 69.1%). One case of NPC with concurrent NPIN was seen among the biopsy specimens, but no case of NPIN was detected cytologically.

CONCLUSIONS

The cytologic pickup of NPC was substantially lower than that obtained on biopsy. More importantly, NPIN was uncommon. Therefore, a screening test that depends on the collection of cells for the microscopic diagnosis of NPIN and NPC is unlikely to have a major impact on the incidence of NPC. Furthermore, obtaining a good cytologic specimen from the nasopharynx is not simple, and this further limits this technique for mass screening purposes. The concept of a cytologic test for NPC, similar to the Pap test for the prevention of uterine cervix cancer, has still to be realized.

Presence of Epstein-Barr virus latent membrane protein 1 gene in the nasopharyngeal swabs from patients with nasopharyngeal carcinoma

BACKGROUND

Nasopharyngeal carcinoma (NPC) is the most common head and neck malignancy in southeastern China and Taiwan. Early detection of the local disease followed immediately by proper treatment is essential to increase the cure and survival rates. Because every NPC tumor cell carries Epstein-Barr Virus (EBV) genomes, detection of EBV genomic DNA such as latent membrane protein 1 gene (LMP1) might indicate the presence of NPC. We developed a simple and noninvasive technique of nasopharyngeal swabbing to acquire nasopharyngeal cells for detecting the presence of EBV genome. The aim of this study was to investigate the feasibility and reliability of this technique.

METHODS

We collected nasopharyngeal cells by means of a nasopharyngeal swabbing technique and detected the presence of EBV LMP1 with polymerase chain reaction (PCR). Thirty-eight swab specimens were obtained from patients with NPC who were newly diagnosed or were just beginning radiotherapy. Two groups of control subjects were recruited, including 20 patients with other head and neck cancers and eight family members of the NPC patients. An additional group of 65 NPC patients were enrolled in the course of regular follow-up after definitive radiotherapy.

RESULTS

All of the samples yielded sufficient DNA for PCR amplification. Thirty-six of 38 NPC swab samples were positive for EBV LMP1, and all the control subjects had swab sample results negative for EBV. All five patients with suspected local recurrence exhibited positive EBV test results.

CONCLUSIONS

Demonstration of EBV LMP1 in the nasopharyngeal swab specimens detected NPC with a sensitivity of 94.7% and specificity of 100%. This study confirms the reliability and feasibility of nasopharyngeal swab in the predicting and screening of NPC.

Lymphoid cell infiltration into Epstein-Barr virus-positive nasopharyngeal carcinomas

OBJECTIVES

A pilot study was designed to analyze lymphoid cell infiltration in Epstein-Barr virus-positive (EBV+) nasopharyngeal carcinomas (NPCs) and to determine whether this pattern of infiltration is consistent with non-EBV+ head and neck carcinomas or with solid EBV+ tumors in other locations.

STUDY DESIGN

We performed a retrospective analysis of archived NPCs and oral cavity carcinomas.

METHODS

Immunohistochemical staining of the archive material for various markers (CD3, CD8, UCHL-1, S-100, and intercellular adhesion molecule) was performed. Polymerase chain reaction techniques to establish the presence of the EBV genome were used. Cells in different locations were counted under a light microscope by 2 of the authors.

RESULTS

The infiltration pattern of NPCs was different from that of oral cavity carcinomas. Stromal infiltration was significantly denser in oral cavity carcinomas. Tumor nest infiltration was more pronounced in NPCs. The pattern of infiltration was comparable with what has been described for other solid EBV+ tumors.

CONCLUSIONS

The immune response to NPCs is likely to be strongly influenced by the presence of the EBV genome. The pattern of infiltration is similar to that of other non-head and neck EBV+ solid tumors and different from that of EBV- head and neck carcinomas.

Telomerase assay and nested polymerase chain reaction from nasopharyngeal swabs for early noninvasive detection of nasopharyngeal carcinoma

The main purpose of this study was to analyze sensitivity and specificity of combining nested polymerase chain reaction for detection of Epstein-Barr virus (EBV) genome and telomerase assay for identifying nasopharyngeal carcinoma (NPC). Eighty patients with NPC and 27 healthy control subjects were included in this study; 97. 5% and 94.9% of NPC patients were positive for EBV genome and telomerase activity, respectively. When nasopharyngeal swabs were tested, 95.7% presented the EBV genome and 85.5% were positive for telomerase expression. The sensitivity for counting either positive result of these two techniques was 100%. Among the 27 control subjects, only 6 and 5 cases were positive for EBV DNA and telomerase activity, respectively. This indicated a specificity of 92.6% when both positive results were included. At present, early diagnosis of NPC requires multiple biopsy specimens, especially to identify subclinical cases. Because this study showed a very high sensitivity for detecting NPC from swabs when combining the telomerase assay and nested polymerase chain reaction technique, this noninvasive technique may be a good candidate for screening of subclinical NPC, especially before multiple biopsy specimens are obtained.