The efficacy of fiberoptic endoscopic examination and biopsy in the detection of early nasopharyngeal carcinoma

Diagnosis of possible nasopharyngeal malignancy in adults with isolated serous otitis media; a systematic review and proposal of a management algorithm

PURPOSE

The objective of this study was (1) to systematically review the evidence of routine post-nasal space blind biopsies and/or imaging of adults with isolated serous otitis media (SOM) of unknown cause for detection nasopharyngeal malignancy (NPM), and (2) to design a clinical management algorithm for these patients.

METHODS

A systematic search was conducted in the databases PubMed, Embase and Cochrane Library guided by the study question "Should adults with isolated SOM of unknown cause undergo routine biopsies of the post-nasal space and/or diagnostic imaging for detection of NPM?". All retrieved studies were reviewed and quantitatively analyzed.

RESULTS

The systematic literature search identified 552 publications accessible for title-abstract screening. This yielded 23 studies for full text assessment, of which 6 were found eligible for inclusion. All six studies dealt with nasopharyngeal blind biopsies, whereas no studies on cross-sectional imaging were identified. The derived summarized results of the included studies showed that 5.5% (31/568) of patients with isolated SOM of unknown cause were diagnosed with NPM. Of these, 6.5% (2/31) had normal nasopharyngeal endoscopy (i.e., malignancy was discovered by blind biopsies). Finally, 0.35% (2/568) of patients with isolated SOM of unknown cause diagnosed with NPM had normal nasopharyngeal endoscopy findings (i.e., nasopharyngeal endoscopy ruled-out malignancy in 99.65% of patients).

CONCLUSIONS

We found no evidence supporting routine use of blind biopsies or cross-sectional imaging in adults with isolated serous otitis media of unknown cause. We propose a pragmatic management algorithm for workup of adults with persistent secretory otitis media.

Comparison of new magnetic resonance imaging grading system with conventional endoscopy for the early detection of nasopharyngeal carcinoma

BACKGROUND

Although stratifying individuals with respect to nasopharyngeal carcinoma (NPC) risk with Epstein-Barr virus-based markers is possible, the performance of diagnostic methods for detecting lesions among screen-positive individuals is poorly understood.

METHODS

The authors prospectively evaluated 882 participants aged 30 to 70 years who were enrolled between October 2014 and November 2018 in an ongoing, population-based NPC screening program and had an elevated NPC risk. Participants were offered endoscopy and magnetic resonance imaging (MRI), and lesions were identified either by biopsy at a follow-up endoscopy or further contact and linkage to the local cancer registry through December 31, 2019. The diagnostic performance characteristics of endoscopy and MRI for NPC detection were investigated.

RESULTS

Eighteen of 28 identified NPC cases were detected by both methods, 1 was detected by endoscopy alone, and 9 were detected by MRI alone. MRI had significantly higher sensitivity than endoscopy for NPC detection overall (96.4% vs 67.9%; P_difference = .021) and for early-stage NPC (95.2% vs 57.1%; P = .021). The sensitivity of endoscopy was suggestively lower among participants who had previously been screened in comparison with those undergoing an initial screening (50.0% vs 81.2%; P = .11). The authors observed a higher overall referral rate by MRI versus endoscopy (17.3% vs 9.1%; P < .001). Cases missed by endoscopy had early-stage disease and were more commonly observed for tumors originating from the pharyngeal recess.

CONCLUSIONS

MRI was more sensitive than endoscopy for NPC detection in the context of population screening but required the referral of a higher proportion of screen-positive individuals. The sensitivity of endoscopy was particularly low for individuals who had previously been screened.

Evaluation of the pharyngeal recess with cone-beam computed tomography

PURPOSE

To evaluate the radiological anatomy of the pharyngeal recess (PR) by gender and age.

METHODS

Images of patients who underwent cone-beam computed tomography (CBCT) were analyzed retrospectively. A total of 600 PRs (140 male, 160 female) were examined. PR depths, distances between the posterior nasal spine (PNS) and the posterior wall of the pharynx, right and left torus levatorius lengths, and distances between the right and left torus levatorius were measured on the axial plane passing through the PNS-basion point.

RESULTS

PR depths differed significantly between age groups (right p = 0.030, left p = 0.047). The PR depths of individuals under 35 years of age were significantly higher than those of individuals aged 35 and over. Further, the distances between the PNS and the posterior wall of the pharynx differed significantly between age groups and between gender groups. The distances between the PNS and the posterior wall of the pharynx were shorter in patients under 35 years of age (p = 0.000). In terms of gender, these distances were significantly longer in males (p = 0.014). The distances between the right and left torus levatorius were also significantly longer in males (p = 0.029).

CONCLUSION

The PR is the region in which nasopharyngeal carcinoma originates most frequently and is very important for early diagnosis. The present results indicated that this region can be examined with CBCT.

The role of cross-sectional imaging in suspected nasopharyngeal carcinoma

INTRODUCTION

Nasopharyngeal carcinoma is a rare neoplasm in the UK. The current gold standard for detection is endoscopic examination under anaesthesia of the nasopharynx with biopsy. Many clinicians are now advocating cross-sectional imaging as the primary investigation. The objective of this study is to evaluate the role of cross-sectional imaging in detecting nasopharyngeal carcinoma and ultimately to avoid unnecessary biopsy.

MATERIAL AND METHODS

This is a retrospective uncontrolled case series review of patients who were investigated for suspected nasopharyngeal carcinoma between 2009 and 2017 at York Teaching Hospital NHS Foundation Trust. At present, any suspected nasopharyngeal carcinoma requires biopsy. Search terms used were 'endoscopic biopsy of nasopharynx', 'endoscopic examination + biopsy nasopharynx'. The main outcome measures are reported histological and radiological features of malignancy. Only patients who had imaging prior to the biopsy were included.

RESULTS

A total of 144 patients had endoscopic examination under anaesthesia of the nasopharynx with biopsy. Approximately one-third of these patients had cross-sectional imaging before the biopsy. The study revealed that magnetic resonance imaging had 100% sensitivity and 84% specificity; however, the endoscopic examination under anaesthesia and biopsy had only 88% sensitivity. This is due to a negative histological finding despite radiological characteristics of nasopharyngeal carcinoma in some patients. However, the specificity was 100%.

CONCLUSION

The study supports magnetic resonance imaging as the primary investigation in patients with suspected nasopharyngeal carcinoma followed by endoscopic examination under anaesthesia and biopsy in cases with suspicious findings on imaging only.

Nasopharyngeal carcinoma presenting as an inconspicuous primary lesion with extensive cavernous sinus involvement and temporal lobe extension: a case report and review of literature

Detection of nodal metastasis in the neck or adjacent structures is common in nasopharyngeal carcinoma (NPC) when there is frank primary disease. Intracranial extension without obvious nasopharyngeal disease is not common. Here, we discuss a patient with NPC that presented with extensive intracranial disease with subtle findings in the nasopharynx.

Screening for nasopharyngeal cancer

BACKGROUND

Nasopharyngeal cancer is endemic in a few well-defined populations. The prognosis for advanced nasopharyngeal cancer is poor, but early-stage disease is curable and a high survival rate can be achieved. Screening for early-stage disease could lead to improved outcomes. Epstein-Barr virus (EBV) serology and nasopharyngoscopy are most commonly used for screening. The efficacy and true benefit of screening remain uncertain due to potential selection, lead-time and length-time biases.

OBJECTIVES

To determine the effectiveness of screening of asymptomatic individuals by EBV serology and/or nasopharyngoscopy in reducing the mortality of nasopharyngeal cancer compared to no screening. To assess the impact of screening for nasopharyngeal cancer on incidence, survival, adverse effects, cost-effectiveness and quality of life.

SEARCH METHODS

The Cochrane Ear, Nose and Throat Disorders Group (CENTDG) Trials Search Co-ordinator searched the CENTDG Trials Register; Central Register of Controlled Trials (CENTRAL 2015, Issue 6); PubMed; EMBASE; CINAHL; Web of Science; Clinicaltrials.gov; ICTRP and additional sources for published and unpublished trials. The date of the search was 6 July 2015.

SELECTION CRITERIA

Randomised controlled trials (RCT) and controlled clinical trials (CCT) evaluating screening for nasopharyngeal cancer versus no screening. Randomisation either by clusters or individuals was acceptable.

DATA COLLECTION AND ANALYSIS

We used the standard methodological procedures expected by The Cochrane Collaboration. Our primary outcome measure was nasopharyngeal cancer-specific mortality. Secondary outcomes were incidence of nasopharyngeal cancer by stage and histopathological classification at diagnosis, survival (two-year, three-year, five-year and 10-year), harms of screening (physical and psychosocial), quality of life (via validated tools such as the SF-36 and patient satisfaction), cost-effectiveness and all-cause mortality.

MAIN RESULTS

We identified no trials that met the review inclusion criteria. We retrieved 31 full-text studies for further investigation following the search. However, none met the eligibility criteria for a RCT or CCT investigation on the efficacy of screening for nasopharyngeal cancer.

AUTHORS' CONCLUSIONS

No data from RCTs or CCTs are available to allow us to determine the efficacy of screening for nasopharyngeal cancer, or the cost-effectiveness and cost-benefit of a screening strategy. High-quality studies with long-term follow-up of mortality and cost-effectiveness are needed.

Hypertrophic adenoids in patients with nasopharyngeal carcinoma: appearance at magnetic resonance imaging before and after treatment

INTRODUCTION

Patients with nasopharyngeal carcinoma (NPC) sporadically develop abnormal adenoids. Nasopharyngeal adenoids are usually included in the gross tumor volume (GTV) but may have different therapeutic responses than tumor tissue. Therefore, distinguishing adenoids from tumor tissue may be required for precise and efficient chemoradiotherapy and radiotherapy. We characterized nasopharyngeal adenoids and investigated the therapeutic responses of NPC and nasopharyngeal adenoids using magnetic resonance imaging (MRI).

METHODS

MRI data from 40 NPC patients with a coexisting adenoid mass before and after treatment were analyzed. The features of the adenoid masses, including location, striped appearance, size, interface, symmetry/asymmetry, and cysts, were evaluated. Treatment response were scored according to the World Health Organization guidelines.

RESULTS

A striped appearance was observed in 36 cases before treatment and in all cases after treatment. In these 36 cases, the average GTVs including and excluding the uninvolved adenoids were 19.8 cm³ and 14.8 cm³, respectively. The average percentage change after excluding the uninvolved adenoids from the GTV was 31.0%. Stable disease in the adenoids was identified in 27 (96.4%) of 28 patients after neoadjuvant chemotherapy, while NPC clearly regressed. Partial adenoid responses were identified in 33 (82.5%) of 40 patients at 3 months after chemoradiotherapy or radiotherapy, whereas complete tumor responses were achieved in all patients. Six months after treatment, the adenoids continued to atrophy but did not disappear, and tumor recurrence was not found.

CONCLUSIONS

Nasopharyngeal adenoids and carcinoma tissue in NPC patients can be distinguished by using MRI and have different responses to chemoradiotherapy and radiotherapy. These findings contribute to better delineating the GTV of NPC, based on which spatially optimized strategies can be developed to render precise and efficient chemoradiotherapy and radiotherapy. Additionally, we observed a clear difference in the responses of these two tissue types to current therapies. This finding may reduce or avoid unnecessary biopsies or overtreatment.

Diagnostic accuracy of sonography versus magnetic resonance imaging for primary nasopharyngeal carcinoma

OBJECTIVES

The purpose of this study was to prospectively assess the accuracy of sonography versus magnetic resonance imaging (MRI) for a diagnosis of primary nasopharyngeal carcinoma.

METHODS

A total of 150 patients suspected of having nasopharyngeal carcinoma underwent sonography and MRI. A diagnosis was obtained from an endoscopic biopsy that was collected from the suspected tumor or a normal nasopharynx. The diagnostic performance of sonography and MRI for nasopharyngeal carcinoma was evaluated by receiver operating characteristic curve analysis. The sensitivity and specificity of the two imaging methods were compared by the McNemar test.

RESULTS

Nasopharyngeal carcinoma was present in 71 of 150 patients (47.3%) and absent in 79 (52.7%). The sensitivity, specificity, and accuracy of sonography versus MRI for these cases were 90.1%, 84.8%, and 87.3% for sonography and 97.2%, 89.9%, and 93.3% for MRI, respectively. Both sonography and MRI had good diagnostic performance for nasopharyngeal carcinoma, with area under the curve values of 0.958 and 0.987, respectively. There was no significant difference in the rate of tumor detectability between sonography and MRI (P = .12), and the specificities of sonography and MRI were similar (P = .22).

CONCLUSIONS

Both sonography and MRI are useful tools for clinical screening of nasopharyngeal carcinoma. However, sonography is less expensive and easier to perform. The results of this study also suggest that nasopharyngeal sonography could be used for the initial investigation of primary cancer in patients suspected of having nasopharyngeal carcinoma.

The diagnostic accuracy of ultrasonography versus endoscopy for primary nasopharyngeal carcinoma

Objective

To compare the accuracy of ultrasonography (US) with the current clinical standard of endoscopy for a diagnosis of nasopharyngeal carcinoma (NPC).

Methods

A total of 150 patients suspected of having NPC underwent US and endoscopy. A diagnosis was obtained from an endoscopic biopsy collected from each suspected tumor and was compared with a biopsy obtained from a normal nasopharynx. The diagnostic accuracy of US and endoscopy for NPC was evaluated using receiver operating curve (ROC) analysis performed by MedCalc Software.

Results

The sensitivity, specificity, and accuracy of US versus endoscopy for this cohort were 90.1%, 84.8%, and 87.3% for US, and 88.7%, 97.5%, and 93.3% for endoscopy, respectively. Both US and endoscopy exhibited good diagnostic accuracy for NPC with area under the curve (AUC) values of 0.929 and 0.938, respectively. However, this difference was not significant (Z = 0.36, P = 0.72).

Conclusion

US is a useful tool for the detection of tumors in endoscopically suspicious nasopharynx tissues, and also for the detection of subclinical tumors in endoscopically normal nasopharynx tissues.

Developing an adaptive radiation therapy strategy for nasopharyngeal carcinoma

Adaptive radiotherapy (ART) has recently been introduced to restore the planned dose distribution by accounting for the anatomic changes during treatment. By quantifying the anatomic changes in nasopharyngeal carcinoma (NPC) patients, this study aimed to establish an ART strategy for NPC cases. A total of 30 NPC patients treated with helical tomotherapy were recruited. In the pretreatment megavoltage CT images, the anatomic changes of the posterolateral wall of nasopharynx (P-NP), neck region and parotid glands were measured and assessed. One-way repeated measure ANOVA was employed to define threshold(s) at any time-point. The presence of a threshold(s) would indicate significant anatomical change(s) such that replanning should be suggested. A pragmatic schedule for ART was established by evaluating the threshold for each parameter. Results showed the P-NP, parotid gland and neck volumes demonstrated significant regressions over time. Respectively, the mean loss rates were 0.99, 1.35, and 0.39 %/day, and the mean volume losses were 35.70, 47.54 and 11.91% (all P < 0.001). The parotid gland shifted medially and superiorly over time by a mean of 0.34 and 0.24 cm, respectively (all P < 0.001). The neck region showed non-rigid posterior displacement, which increased from upper to lower neck. According to the threshold occurrences, three replans at 9th, 19th and 29th fractions were proposed. This ART strategy was able to accommodate the dosimetric consequences due to anatomic deviation over the treatment course. It is clinically feasible and would be recommended for centers where an adaptive planning system was not yet available.

Systematic review on Epstein-Barr virus (EBV) DNA in diagnosis of nasopharyngeal carcinoma in Asian populations

OBJECTIVE

To conduct a meta-analysis to investigate the value of EBV DNA in diagnosis of nasopharyngeal cancer (NPC) in Asian populations, and provide important evidence for screening.

METHODS

Prospective or respective case-control or cohort studies regarding the detection role of EBV DNA for NPC were included in our study. We conducted a comprehensive literature search in PubMed, EMBASE, and the Chinese Biomedical Database (CBM database between January 1980 and March 2012.

RESULTS

A total of 18 studies with 1492 NPC cases and 2641 health controls were included. Almost of the included studies were conducted in China, and only one other conducted in Thailand. The overall results demonstrated that the pooled sensitivity, specificity, positive likelihood (+ LR) and negative likelihood (-LR) were 0.73 (0.71-0.75), 0.89 (0.88-0.90), 8.84 (5.65-13.84) and 0.19(0.11-0.32), respectively. The overall EBV DNA detection showed the largest area of 0.932 under the summary receiver operator curve (SROC). The accuracy of detection by plasma for NPC (0.86) was higher than in serum (0.81), with largest areas under the SROC of 0.97 and 0.91, respectively.

CONCLUSION

Our results demonstrated the EBV DNA detection in plasma or serum has high sensitivity and specificity in diagnosis of NPC, especially in Chinese populations with a high risk of cancer.

The progress on genetic analysis of nasopharyngeal carcinoma

Nasopharyngeal carcinoma (NPC) is a rare malignancy in most parts of the world, but is one of the most common cancers in Southeast Asia. Both genetic and environmental factors contribute to the tumorigenesis of NPC, most notably the consumption of certain salted food items and Epstein-Barr virus infection. This review will focus on the current progress of the genetic analysis of NPC (genetic susceptibilities and somatic alterations). We will review the current advances in genomic technologies and their shaping of the future direction of NPC research.

Endoscopic Assessment of the Nasopharynx: An Objective Score of Abnormality to Predict the Likelihood of Malignancy

Objectives:

We developed an objective endoscopic score of abnormality of the nasopharynx to predict the likelihood of malignancy.

Methods:

A score sheet with 44 variables was developed to objectively quantify the bilateral endoscopic assessment of the nasopharynx. Patients scheduled to undergo nasopharyngeal biopsies were recruited. The nasopharynx was assessed endoscopically, photographed, and scored on 44 variables. The scores were compared to the biopsy results, and predictors of malignancy were modeled with regression analysis. The sensitivity and specificity of the novel scoring system were examined.

Results:

Seventeen patients had carcinoma, and 60 had a benign lesion or no disease. Patients with a nasopharyngeal malignancy scored significantly higher than did patients with a benign lesion or no disease. No patient with a malignant lesion had a score of less than 12. With a receiver operating characteristic curve area of 0.917, the score demonstrated an excellent ability to discriminate between nasopharynges that were likely or unlikely to contain malignant disease. Independent predictors for both malignant disease and a score greater than 12 were modeled.

Conclusions:

A cutoff score above 12 on the novel objective endoscopic assessment of the nasopharynx measure was highly predictive of possible malignancy.

Molecular diagnosis of nasopharyngeal carcinoma using detection of Epstein-Barr virus latent membrane protein-1 gene in cervical metastatic lymph nodes

BACKGROUND

Cervical lymphadenopathy could be a manifestation of occult nasopharyngeal carcinoma (NPC). Epstein-Barr virus (EBV) is frequently detected in NPC, and its malignant transformation is associated through the action of the oncoprotein latent membrane protein-1 (LMP-1).

PURPOSE

The aim of this study was to investigate whether a primary nasopharyngeal origin could be localized by detection of EBV LMP-1 gene in cervical metastatic lymph nodes.

MATERIALS AND METHODS

In this prospective study, 32 paraffin-embedded tissues of various head and neck carcinomas and 20 normal tonsil specimens were examined for the presence of LMP-1 gene, using polymerase chain reaction.

RESULTS

Ten of 12 nasopharyngeal biopsies and 8 of 10 metastatic lymph nodes of the same NPC were positive for LMP-1 gene. The LMP-1 gene was detected in metastatic lymph nodes of NPC, with a sensitivity of 80%, specificity of 100%, positive predictive value of 100%, and negative predictive value of 91%. On the contrary, the LMP-1 gene was not detected in any of the samples of other head and neck carcinomas and their metastatic nodes as well as in tonsillar specimens. There was a significant association between the presence of LMP-1 gene and tumor location in the nasopharynx (P < .0001).

CONCLUSION

The presence of LMP-1 gene in metastatic cervical lymph nodes is significantly associated with nasopharyngeal origin of the carcinoma. Meanwhile, EBV has no role in the tumorigenesis of carcinomas arising from other head and neck regions.

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.

Fine-needle aspiration cytology of metastatic nasopharyngeal carcinoma

Cytological features of nasopharyngeal carcinoma (NPC) were reviewed in an attempt to select cytological criteria that permit a specific recognition of metastases. For this purpose, 54 fine-needle aspiration (FNA) procedures from 43 patients with NPC were analyzed. Thirty-two (59.3%) procedures were performed before the histological diagnosis. In 25 (46.3%) procedures, smears showed many neoplastic single cells, clusters, and abundant lymphoid cells (mixed pattern). A dissociated (single cell) pattern consisting of individual neoplastic and lymphoid cells was seen in 18 (33.3%) cases. Finally, 11 (20.4%) cases showed cohesive epithelial clusters (cohesive pattern) without relevant cellular dissociation or lymphoid cells. Squamous-cell differentiation was seen in three of these cases. Most single neoplastic cells presented as large, pleomorphic naked nuclei. Other interesting findings were granulomas (n = 3), prominent eosinophilic infiltrates (n = 4), and suppurative changes (n = 5). In most smears with mixed and dissociated patterns, a nasopharyngeal origin could be suggested. On the contrary, those smears with a cohesive pattern were indistinguishable from other head and neck carcinomas. The presence (on cervical lymph nodes) of a dissociated or mixed (single cells and groups) architectural pattern of large, anaplastic cells and naked nuclei accompanied by an abundant lymphoid component is highly suggestive of undifferentiated NPC. Cytology offers a rapid diagnosis, establishes the necessity of a complete cavum examination, and helps in avoiding unnecessary and harmful biopsies.

Monitoring tumor recurrence with nasopharyngeal swab and latent membrane protein-1 and epstein-barr nuclear antigen-1 gene detection in treated patients with nasopharyngeal carcinoma

OBJECTIVES

Epstein-Barr virus (EBV) is closely related to nasopharyngeal carcinoma (NPC). Detection of EBV genomic DNA in a nasopharyngeal swab specimen may indicate the presence of NPC, and the EBV genomic DNA is only detected in patients with NPC and not in other head and neck cancers. This study aims to prove that detection of EBV genomic DNA by means of the latent membrane protein (LMP)-1 gene and the Epstein-Barr nuclear antigen (EBNA)-1 gene in the nasopharynx in NPC patients after radiation therapy indicates local recurrence of NPC.

STUDY DESIGN

Prospective.

METHODS

Nasopharyngeal swab with polymerase chain reaction (PCR)-based LMP-1 and EBNA-1 gene detection was used to monitor local recurrence in 84 NPC patients who completed radiation therapy.

RESULTS

Of the 12 patients demonstrating positive LMP-1 and EBNA-1 gene, 11 had local recurrence, and 10 of them had early rT1 mucosal recurrence. Subsequent salvage nasopharyngectomy controlled local disease in nine. Only one local recurrence in the skull base failed to show LMP-1 gene initially. Detection of LMP-1 gene and later verification with EBNA-1 gene from nasopharyngeal swabs in NPC patients after radiation therapy predicted local recurrence with a sensitivity of 91.7% and a specificity of 98.6%.

CONCLUSIONS

Nasopharyngeal swab with LMP-1 and EBNA-1 gene detection is a useful and reliable method to monitor local recurrence in NPC patients. It helps to detect recurrence early and may improve local control and enhance survival.

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.

Quantitative analysis of plasma cell-free Epstein-Barr virus DNA in nasopharyngeal carcinoma after salvage nasopharyngectomy: A prospective study

BACKGROUND

The quantity of circulating cell-free Epstein-Barr virus (EBV) DNA in patients with nasopharyngeal carcinoma (NPC) managed by radiotherapy has prognostic relevance. We measured the copy number of EBV DNA in patients with early recurrent NPC before and after salvage nasopharyngectomy.

METHODS

Nasopharyngectomy with the maxillary swing approach was performed for 28 patients. Serum blood samples were taken prospectively before nasopharyngectomy and on postoperative day 7. Plasma cell-free EBV DNA copies were measured with a real-time quantitative polymerase chain reaction for the BamHI-W fragment of the EBV genome.

RESULTS

Cell-free EBV DNA was detected in 17 patients before nasopharyngectomy. Surgical resection reduced the copy number of EBV DNA significantly (p = .016). Negative surgical margins achieved during nasopharyngectomy is associated with a zero EBV DNA copy postoperatively (p = .022).

CONCLUSION

Cell-free EBV DNA was detected in 61% of patients with recurrent NPC, and its quantity postoperatively reflects whether the salvage nasopharyngectomy has achieved a negative surgical margin.

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.

Nasopharyngeal carcinomas: an update

Among the group of head and neck cancers, nasopharyngeal carcinomas (NPC) represent a distinct entity in terms of their epidemiology, clinical presentation, biological markers, carcinogenic risk factors, prognostic factors, treatment and outcome. Undifferentiated NPC (UCNT), the most frequent histological type, is endemic in certain regions, especially in South East Asia. The disease has also been associated with the presence of the Epstein-Barr Virus (EBV). Although NPC is a radiosensitive and chemosensitive tumour, a substantial number of patients develop local recurrence or distant metastases. For patients with locoregional advanced disease, it is well known that conventional radiotherapy is insufficient in terms of both the local control rates and distant metastases. New techniques of radiation and new combined radiotherapy and chemotherapy modalities have been evaluated in numerous clinical trials in recent years. The purpose of this article is to review the current knowledge in terms of the epidemiology, biology, prognosis, management and outcome of patients with NPC.

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.

Unilateral palate paralysis in patients with nasopharyngeal carcinoma: imaging and clinical correlations

OBJECTIVE

Neck masses, hearing impairment, and blood-tinged nasal discharges are three major clinical manifestations of nasopharyngeal carcinoma (NPC). Because of the relationship between the anatomic structures of the fossa of Rosenmüller and the levator veli palatini muscle, NPC arising in the fossa can invade the levator muscle, limiting movement or causing paralysis of the ipsilateral soft palate. It is well known that NPC originates commonly from the fossa of Rosenmüller. We therefore hypothesize that the clinical signs of unilateral palate paralysis in patients with NPC must be far more common than usually realized. This issue is, as yet, not fully addressed in the literature.

STUDY DESIGN

A prospective study of all patients with newly diagnosed NPC.

METHODS

Two hundred sixty-four patients with newly diagnosed NPC were studied. Clinical records included the details of their clinical presentations and the results of physical and neurological examinations. The degree of elevation of the soft palate during phonation was carefully evaluated. Magnetic resonance imaging (MRI) of the head and neck region with a particular emphasis on the levator veli palatini muscles was then performed. The degree of paralysis of the palate was correlated with the degree of invasion of the levator muscles by the tumor, as seen with imaging. The incidence of paralysis of the palate in the patients with NPC was also determined.

RESULTS

At the time of diagnosis, ipsilateral paralysis of the palate was observed in 137 (52%) of the 264 patients with NPC. The results of imaging indicated that 62% (163 of 264) of the patients had radiological evidence of tumor invasion of the levator muscle. The degree of paralysis of the palate corresponded well to the extent of tumor invasion of the levator muscle. Paralysis of the palate was not evident in 26 patients with early perimuscular infiltration of the levator muscle.

CONCLUSION

This study revealed that ipsilateral invasion of the levator veli palatini muscle by NPC is common and typically presents with signs of unilateral palate paralysis. This subtle sign is relatively common in patients with NPC. Consequently, we think palate function should be routinely tested when diagnosing NPC, particularly when the patient has unilateral aural symptoms or a neck lump.

Examination of nasopharyngeal epithelium with contact endoscopy

Primarily to evaluate the potential of contact endoscopy, the nasopharyngeal mucosa were examined using contact microscopy. With contact endoscopy it has been possible to visualize (60 x, 150 x ) the superficial cell layers of the nasopharyngeal epithelium, previously stained with methylene blue in vivo and in situ. Normal nasopharyngeal epithelium (20 cases) and cases with pathology (18 cases of chronic nasopharyngitis, 5 cases of nasopharyngeal cyst, and 57 cases of poorly differentiated squamous carcinoma) were assessed with contact endoscopy. The results showed that contact endoscopy can offer clear morphology and arrangement of the epithelial cells of the superficial layers and microvascular networks, such as the size and shapes of the cells or nuclei, nucleus/cytoplasm ratio, karyokinesis, etc. Our study indicated that contact endoscopy can permit the mapping of cellular alteration over mucosa and constitutes a new method of monitoring a high-risk population or precancerous lesions of nasopharyngeal carcinoma.

Diagnostic value of Epstein-Barr viral serology in nasopharyngeal carcinoma

Although Epstein-Barr virus (EBV) IgA serology has been established as an effective marker for nasopharyngeal carcinoma (NPC), it remains unclear how useful or cost-effective it is as a screening test. This article is aimed at establishing how these tests could be used most effectively in the diagnosis of NPC in an otolaryngology outpatient clinic. A total of 111 consecutive patients with NPC and an equal number of control subjects were studied. Forty-seven patients with NPC had early (AJCC stages 1 and 2) and 64 had advanced (stages 3 and 4) disease. A positive early antigen (EA) serology result was found in 81.2% of NPC patients and in none of the controls. Negative EA and viral capsid antigen (VCA) serology results were present in 2.7% of NPC patients and in 46.8% of controls. Negative EA and positive VCA serology results were found in 30.0% of NPC patients with early disease, 7.8% of NPC patients with advanced disease, and 53.2% of controls. Given its high specificity, serology for EA is recommended as a clinically useful screening test. Serology for VCA, although highly sensitive, has an unacceptably high false-positive rate, and its cost-effectiveness as a universal screening test is questionable.

Preliminary study of in vivo autofluorescence of nasopharyngeal carcinoma and normal tissue

BACKGROUND AND OBJECTIVE

In nasopharyngeal cancer, conventional white light endoscopy does not provide adequate information to detect the flat/small lesion and identify the margin of observable tumor. In the present study, we evaluate the potential of light-induced fluorescence spectroscopic imaging for the localization of cancerous nasopharyngeal tissue.

STUDY DESIGN/MATERIALS AND METHODS

We built a multiple channel spectrometer specifically for the investigation of fluorescence collected by a conventional endoscopic system. Nasopharyngeal fluorescence were measured in vivo from 27 subjects during the routine endoscopy. The biopsy specimens for histologic analysis were taken from the tissue sites where the fluorescence were measured.

RESULTS

Two algorithms to discriminate the nasopharyngeal carcinoma from normal tissue were created based on the good correlation between the tissue autofluorescence and histologic diagnosis. For the two-wavelength algorithm, carcinoma can be differentiated from normal tissue with a sensitivity and specificity of 93% and 92%, respectively. For the three-wavelength algorithm with compensation of variation of blood content in tissue, a sensitivity of 98% and specificity of 95% were achieved.

CONCLUSION

Fluorescence endoscopic imaging used with the algorithms developed in this report is an efficient method for detecting the nasopharyngeal carcinoma.

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

BACKGROUND

Nasopharyngeal carcinoma (NPC) is an important tumor in many countries. Ethnic and regional factors strongly influence disease risk. NPC is usually diagnosed late in disease development, and 10-year survival rates are as low as 10%. Epstein-Barr virus (EBV), a possibly causative agent, is present in all cells of essentially all undifferentiated NPCs. We wished to determine the following: 1) whether an ambulatory nasopharyngeal brush biopsy could provide sufficient tumor cell DNA for the detection of EBV and 2) whether the detection of EBV in this locale reflects the presence of tumor cells or simply EBV carrier status.

METHODS

We collected nasopharyngeal tissue via ambulatory brush biopsies from 21 patients with newly diagnosed NPC and from 157 subjects with other otolaryngologic complaints. The majority of study subjects were from high-risk populations. Sample DNA was analyzed for the presence of EBV genomic sequences by use of the polymerase chain reaction (PCR).

RESULTS

Ninety-six percent of samples yielded sufficient DNA for PCR amplification. Nineteen of 21 patients with NPC brushed positive for EBV DNA, while all but two (1.3%) of 149 informative control subjects were negative for EBV (two-sided P<.0001). One of the EBV-positive control subjects had an EBV-positive inverted sinonasal papilloma; the other EBV-positive control subject exhibited no overt clinical disease.

CONCLUSION

Demonstration of EBV DNA in nasopharyngeal brush biopsy specimens detects NPC with a sensitivity of at least 90% (95% confidence interval = 89.63%-91.32%) and a specificity of approximately 99% (95% confidence interval = 98.64%-98.68%). This technique merits further testing as a possible ambulatory screening strategy in high-risk populations.

Routine nasopharyngeal biopsy in adult secretory otitis media

This study was to determine whether routine examination under anaesthesia and nasopharyngeal biopsy in adults presenting with deafness due to secretory otitis media (SOM) is necessary for detection of nasopharyngeal malignancy. Two patient groups were studied. The first comprised 72 adults with SOM. Of these patients, 3 had nasopharyngeal tumours, 2 of whom also had cervical lymphadenopathy. The prevalence of malignancy in patients with SOM but no other suspicious signs was 1/72 (1.4%). The second group comprised 66 patients receiving treatment for nasopharyngeal neoplasms. In this group, 8 patients had SOM at presentation, 7 of whom had other features suspicious of malignancy. SOM as the sole presenting feature of nasopharyngeal malignancy was 1/66 (1.5%). EUA and biopsy of the nasopharynx is a cost effective investigation which continues to be indicated in adults presenting with deafness due to SOM.