Diagnosis Of Nasopharyngeal Carcinoma Research Articles

Aspergillus pachymeningitis mimicking nasopharyngeal carcinoma

We report a case of otogenic fungal pachymeningitis in a diabetic patient who presented with multiple cranial nerve palsies and nasopharyngeal swelling. We present a case report, we describe the investigations, management and clinical course of fungal pachymeningitis, and we present a review of the world literature on fungal and non-fungal pachymeningitis. To our knowledge, this is the first report of fungal pachymeningitis with magnetic resonance imaging features suggestive of nasopharyngeal carcinoma. It is also the first reported case with aspergillus cultured from both a dural biopsy and the ear canal. Fungal pachymeningitis is a rare condition which may present to otorhinolaryngologists. Its clinical and radiological findings can be confused with those of nasopharyngeal carcinoma; fungal pachymeningitis should thus be included in the differential diagnosis of nasopharyngeal carcinoma.

Prognostic factors and long‐term outcomes of childhood nasopharyngeal carcinoma

The authors studied the survival and long-term morbidities of children with nasopharyngeal carcinoma (NPC). This was a retrospective review of children with NPC who were treated at St. Jude Children's Research Hospital between 1961 and 2004. Prognostic factors and long term effects of therapy were analyzed. Fifty-nine patients (median age, 14.1 years) were identified. Most were male (66.1%) and black (54.2%) and had lymphoepithelioma (93.2%). Thirty-five patients had stage IV disease (59.3%), 20 patients had stage III disease (33.9%), and 4 patients had stage II disease (6.8%). All patients received radiotherapy (RT) to the primary tumor, and most received cervical RT (98.3%) and chemotherapy (88.1%). The 15-year survival and event-free survival (EFS) rates were 67.2% ± 7.5% and 63.5% ± 7.8%, respectively. Five patients (8.5%) developed subsequent malignancies 8.6 to 27 years after NPC diagnosis. EFS was improved in patients who were diagnosed after 1980 (74.8% ± 10% vs 45.5% ± 10.1%; P = .031), in patients who had stage III disease compared with patients who had stage IV disease (79.3% ± 9.6% vs 56.2% ± 11.8%; P = .049), in patients who received cisplatin (81% ± 10.7% vs 45.8% ± 9.7%; P = .013), and in patients who received ≥ 50 grays of RT (71.4% ± 9.3% vs 43.8% ± 11.6%; P = .048). White patients had higher distant failure rates than black patients (41.7% ± 10.4% vs 15.6 ± 6.5%; P = .045). The 15-year cumulative incidence (CI) of any morbidity was 83.7% ± 5.4%, the CI of sensorineural hearing loss was 52.9% ± 6.7%, the CI of primary hypothyroidism was 42.7% ± 6.6%, and the CI of growth hormone deficiency (GHD) was 14.1% ± 4.7%. Dose-response relations were observed between the RT dose and primary hypothyroidism and GHD. The outcome of children with NPC improved over the past 4 decades with the use of cisplatin-based chemotherapy and higher RT doses. However, many survivors had long-term treatment-related morbidities.

CT-guided needle biopsy through mandibular area for the diagnosis of nasopharyngeal carcinoma in the parapharyngeal space

The primary submucous type of nasopharyngeal carcinoma (NPC) or the recurrent NPC in the parapharyngeal space is difficult to be diagnosed histologically by conventional biopsy because of the obstruction of the surrounding structures. This study was performed to evaluate the needle biopsy approach through the madibular area into the parapharyngeal space under the guidance of computed tomography (CT) for NPC. Between July 6, 2005 and October 23, 2009, a total of 6 patients were enrolled into the study. Two patients with cervical lymph node metastasis were clinically suspicious of NPC according to their clinical manifestations. However, no cancer cell could be found by repeated nasopharyngeal biopsies followed by histologic examinations. The other 4 patients were diagnosed with recurrent NPCs by magnetic resonance imaging (MRI) or/and positron emission tomography (PET)-CT scan, showing tumors in the parapharyngeal spaces in 3 patients and enlarged retropharyngeal lymph node in 1 patient. The CT-guided puncture was performed through the mandibular skin and the cutting needle biopsy was taken at the parapharyngeal space focus. All the cutting needle biopsies of projected locations have been performed safely. Finally, all the 7 specimens met the requirement of pathologic diagnosis and the cases were all confirmed histologically to be NPCs. The main complication was mild ache at the puncture point. No blood vessel or nerve was injured and no patient needed special treatment. The CT-guided puncture biopsy of the parapharyngeal space through the mandibular area is simple and feasible. It can be an additional option for routine nasopharyngeal biopsy.

Detection of nasopharyngeal carcinoma using surface-enhanced laser desorption and ionization mass spectrometry profiles of the serum proteome

Early diagnosis of nasopharyngeal carcinoma (NPC) is difficult due to the insufficient specificity of the conventional examination method. This study was to investigate potential and consistent biomarkers for NPC, particularly for early detection of NPC. A proteomic pattern was identified in a training set (134 NPC patients and 73 control individuals) using the surface-enhanced laser desorption and ionization-mass spectrometry (SELDI-MS), and used to screen the test set (44 NPC patients and 25 control individuals) to determine the screening accuracy. To confirm the accuracy, it was used to test another group of 52 NPC patients and 32 healthy individuals at 6 months later. Eight proteomic biomarkers with top-scored peak mass/charge ratios (m/z) of 8605 Da, 5320 Da, 5355 Da, 5380 Da, 5336 Da, 2791 Da, 7154 Da, and 9366 Da were selected as the potential biomarkers of NPC with a sensitivity of 90.9% (40/44) and a specificity of 92.0% (23/25). The performance was better than the current diagnostic method by using the Epstein-Barr virus (EBV) capsid antigen IgA antibodies (VCA/IgA). Similar sensitivity (88.5%) and specificity (90.6%) were achieved in another group of 84 samples. SELDI-MS profiling might be a potential tool to identify patients with NPC, particularly at early clinical stages.

Combination of Epstein–Barr virus scaffold (BdRF1/VCA-p40) and small capsid protein (BFRF3/VCA-p18) into a single molecule for improved serodiagnosis of acute and malignant EBV-driven disease

Current single Epstein–Barr virus (EBV) markers fail to reach 100% sensitivity for serodiagnosis of acute and malignant diseases associated with EBV infection. Previous study had identified immunodominant epitopes of VCA-p40 and VCA-p18, and indicated that these two VCA antigens may have diagnostic value for EBV-related diseases. A recombinant protein of the full-length BdRF1 fused to the immunodominant domain of BFRF3 as 6-his tagged protein in Escherichia coli was developed. The recombinant protein was extracted in 8M urea solution and purified by metal-affinity chromatography yielding a 55kDa product (VCA-p40+18). VCA-p40+18 blot-strips examined for IgM reactivity in infectious mononucleosis samples yielded 100% sensitivity and specificity, with improved reactivity compared with IgM/VCA-p18-ELISAs.A recent study described a synthetic peptide-based IgA/[EBNA1+VCA-p18]-ELISA (IgA/EBV-ELISA), with a sensitivity of 90% for diagnosing nasopharyngeal carcinoma. Immunoblot analysis of biopsy-confirmed nasopharyngeal carcinoma cases with low or negative IgA/EBV-ELISA showed 100% IgG reactivity to VCA-p40 and VCA-p18 proteins. Evaluation of VCA-p40+18 as an additional marker for screening and diagnosis of nasopharyngeal carcinoma was carried out. The data showed positive IgA/VCA-p40+18 reactivity by ELISA for 63.6% (14 of 22) nasopharyngeal carcinoma samples that were missed by peptide-based IgA/EBV-ELISA, suggested VCA-p40+18 as an improved marker for nasopharyngeal carcinoma serodiagnosis. The VCA-p40+18 may be combined with an EBNA1 synthetic peptide as an antigen mixture in one or separate IgA ELISA for improved nasopharyngeal carcinoma serodiagnosis.

Identification of candidate nasopharyngeal carcinoma serum biomarkers by cancer cell secretome and tissue transcriptome analysis: Potential usage of cystatin A for predicting nodal stage and poor prognosis

Nasopharyngeal carcinoma (NPC) is usually diagnosed at advanced clinical stages, resulting in poor outcomes. To discover serum biomarkers for improved NPC diagnosis and/or management, we simultaneously analyzed the NPC cell secretome and tissue transcriptome to identify candidate genes/proteins that are highly upregulated in NPC tissues and also secreted/released from NPC cells. Among the 30 candidates identified, 11 proteins were chosen for further validation using the serum samples from NPC patients and healthy controls, including cystatin A, cathepsin B, manganese superoxide dismutase and matrix metalloproteinase 2. The results showed that serum levels of all the four proteins were indeed higher in NPC patients versus healthy controls and that the use of a three-marker panel (cystatin A, manganese superoxide dismutase and matrix metalloproteinase 2) can contribute to a better NPC detection than each marker alone. In addition, a higher pretreated serum level of cystatin A was found to be associated with a higher nodal stage and poorer prognosis of NPC patients and cystatin A could modulate the migration and invasion of NPC cells in vitro. Altogether, our results indicate that analysis of both the cancer cell secretome and tissue transcriptome is a feasible strategy for efficient identification of novel NPC serum marker panel.

Expression of VCA genes of Epstein-Barr virus in Pichia pastoris and clinical application

Objective To analyze the application of recombinant VCA-BALF4(S) and VCA-BFRF3 proteins in serological diagnosis of nasopharyngeal carcinoma (NPC). Methods DNA extracted from the B95-8 cells was used as the templates in a polymerase chain reaction(PCR). VCA-BALF4 1008 bp (S) (aa 287-623) and VCA-BFRF3 531 bp(177 as) were generated and inserted into pPICZaA vector.The recombinant plasmids were transformed into GS115 yeast by electroporation. The yeast transformants in-duced by methanol expressed recombinant proteins. The recombinant proteins synthesized were coated to mi-croplate for detection of EBV-IgA antibody in NPC patients by ELISA. Results We have successfully se-cretly expressed the recombinant VCA-BALF4(S) and VCA-BFRF3 protein in the Pichia pastoris. The mo-lecular weight of products were approximately 37×10~3 and 18×10~3, respectively. The recombinant proteins VCA-BALF4(S) and VCA-BFRF3 in the culture supematant showed good immunoreactivity with IgA anti-bodies to EBV by Western blot. A novel ELISA was established using Pichia pastoris-expressed VCA-BALF4 (S) and VCA-BFRF3 proteins. Serum samples were collected from patients with NPC and healthy controls and using this ELISA tested. The sensitivity of VCA-BALF4(S) and VCA-BFRF3 tests in the NPC sera were 88.7% and 71.0%, whereas the specificity of normal individuals are 96.4% and 91.8% separately. Con-clusion The recombinant proteins BALF4 (S) and BFRF3 were highly secretly expressed in Pichia pastoris,the diagnostic value of two recombinant proteins in screening for NPC patients were primary evaluated and the valuable pPICZa-BALF4(S) yeast strain was obtained. Key words: Nasopharyngeal carcinoma; BALF4; BFRF3; Pichia pastoris

Early monitoring of radiotherapeutic effects of nasopharyngeal carcinoma xenografts in nude mice using 18F-FDG PET-CT imaging

Monitoring the therapeutic effects of radiotherapy for nasopharyngeal carcinoma (NPC) is critical to providing individualized treatment. This in-vivo study was initially designed to evaluate the therapeutic effect of radiotherapy using 18F-fluorodeoxyglucose positron emission tomography with computed tomography (18F-FDG PET-CT) imaging. 18F-FDG PET-CT imaging was performed on all of the 10 nude mice bearing NPC xenografts before radiotherapy, and early-phase and delayed-phase PET-CT images were performed on 7 of the 10 mice. All mice were randomly divided into either a control group or a radiotherapy group. The 5 mice in the control group were immediately killed after the imaging and pathology were performed. After receiving radiotherapy of 12 Gy, 5 animals in the radiotherapy group were given 18F-FDG PET-CT imaging on days 2, 4, and 6, and then were killed for pathologic evaluation. Regions of interest (ROI) technology was used to measure the tumor target/non-target (T/NT) ratio and the volume of the tumors. The average T/NT ratios of early- and delayed-phase imaging were 1.806 +/- 0.532 and 1.777 +/- 0.597, respectively, with no significance (P > 0.05). For the radiotherapy group, the average T/NT ratios for 18F-FDG PET-CT before radiotherapy, and on days 2, 4, and 6 after radiotherapy, were 1.735 +/- 0.466, 1.818 +/- 0.396, 1.096 +/- 0.101, and 0.604 +/- 0.108, respectively, The tumor volumes were (1.48 +/- 0.27) cm3, (1.57 +/- 0.31) cm3, (1.59 +/- 0.31) cm3 and (1.60 +/- 0.29) cm3, respectively. The average T/NT ratios of day 6 after radiotherapy and the other time points were significant (P < 0.05). The average death ratio of the tumor cells was (93.00 +/- 7.42)% after 6 days of post-radiotherapy. 18F-FDG PET-CT imaging can be used for the early assessment of radiotherapeutic effect of NPC in vivo. Day 6 after radiotherapy may be an appropriate time point for the imaging. However, the T/NT ratio measurement of delayed-phase imaging might make no sense for the diagnosis of NPC.

Development of new methods for the diagnosis of nasopharyngeal carcinoma

Development of new methods, ELISA and immunostrip test, for the diagnosis of nasopharyngeal carcinoma. The engineering purified antigens coat plate or absorb on nitrocellulose filter. The plate and diagnostic strips carrying antigens were used for detection of IgG antibody in the sera from nasopharyngeal carcinoma patients and outpatients patients. 127 cases sera from nasopharyngeal carcinoma patients were parallel detected TK/IgG antibody by ELISA and immunostrips. The TK/IgG antibody are all positive in the 127 cases of nasopharyngeal carcinoma patients. 55 cases show positive by ELISA, 58 cases positive by immunostrips in 247cases sera from outpatient. The antibody positive rate to early antigen p54 lower then to TK. Conclusion ELISA and imuunostrips are sensitive and specific means for detection of the IgG antibody to TK of EBV and the diagnosis of nasopharyngeal carcinoma.

Novel Epstein-Barr virus immunoglobulin G–based approach for the specific detection of nasopharyngeal carcinoma

Purpose This study was designed to find a reliable Epstein-Barr virus (EBV) immunoglobulin (Ig) G–based diagnostic/screening test for nasopharyngeal carcinoma (NPC) able to demarcate between the NPC-related seropositivity of EBV IgG antibodies and that of other head and neck cancer (HNCA) and control groups. The NPC-associated immunosuppression affects EBV IgA much more than IgG, leading to inconsistent detection of NPC using EBV IgA antibodies. Materials and methods One hundred twenty-two HNCA patients, 42 NPC, 66 laryngeal carcinoma, and 14 hypopharyngeal carcinoma and 3 groups of 100 control subjects were enrolled in this study. Enzyme-linked immunosorbent assay (ELISA) was used to find a specific cutoff value for the NPC-related seropositivity of EBV IgG antibodies. Results NPC group showed higher serum level of EBV IgG antibodies than control and other HNCA groups ( P < .05). However, the traditional cutoff value, mean + 2 SDs of control subjects, failed to demarcate the seropositives of NPC patients from those of healthy population ( P > .05). The new cutoff value, mean + 2 SDs of the seropositives group of control subjects who had already been grouped by the traditional cutoff value, proved successful. It succeeded to demarcate between the NPC-related EBV IgG seropositivity and that issued from the persistent, latent, or reactivated EBV infection in the population ( P < .05). The sensitivity/specificity of NPC detection by the new cutoff-based ELISA kit, 76.19% and 86%, was close or higher than that of EBV IgA antibodies. Conclusion EBV IgG-based ELISA could be used for the diagnosis of NPC using a new cutoff threshold that excludes the population baseline of EBV IgG seropositivity.

Clinical values of multiple Epstein-Barr virus (EBV) serological biomarkers detected by xMAP technology

BackgroundSerological examination of Epstein-Barr virus (EBV) antibodies has been performed for screening nasopharyngeal carcinoma (NPC) and other EBV-associated diseases.MethodsBy using xMAP technology, we examined immunoglobulin (Ig) A antibodies against Epstein-Barr virus (EBV) VCA-gp125, p18 and IgA/IgG against EA-D, EBNA1 and gp78 in populations with distinct diseases, or with different genetic or geographic background. Sera from Cantonese NPC patients (n = 547) and healthy controls (n = 542), 90 members of high-risk NPC families and 52 non-endemic healthy individuals were tested. Thirty-five of NPC patients were recruited to observe the kinetics of EBV antibody levels during and after treatment. Patients with other EBV-associated diseases were collected, including 16 with infectious mononucleosis, 28 with nasal NK/T cell lymphoma and 14 with Hodgkin's disease.ResultsBoth the sensitivity and specificity of each marker for NPC diagnosis ranged 61–84%, but if combined, they could reach to 84.5% and 92.4%, respectively. Almost half of NPC patients displayed decreased EBV immunoactivities shortly after therapy and tumor recurrence was accompanied with high EBV antibody reactivates. Neither the unaffected members from high-risk NPC families nor non-endemic healthy population showed statistically different EBV antibody levels compared with endemic controls. Moreover, elevated levels of specific antibodies were observed in other EBV-associated diseases, but all were lower than those in NPC.ConclusionCombined EBV serological biomarkers could improve the diagnostic values for NPC. Diverse EBV serological spectrums presented in populations with different EBV-associated diseases, but NPC patients have the highest EBV activity.

IgA antibodies against the Epstein‐Barr nuclear antigen1 as a valuable biomarker for the diagnosis of nasopharyngeal carcinoma in Tunisian patients

Serological tests for Epstein-Barr virus (EBV) have been used for many years as diagnostic predictors of nasopharyngeal carcinoma. It has been shown previously that the conventional immunofluorescence assay has a limited diagnostic value, especially in young patients from North African area. In the search for more reliable immunoglobulin (Ig) G or IgA antibody markers for the diagnosis of nasopharyngeal carcinoma, immunoblot analysis was performed using a full spectrum of EBV proteins. Sera were collected from 108 patients with nasopharyngeal carcinoma and three control groups composed of 18 patients with lymphoma, 18 other patients with autoimmune diseases and 55 healthy EBV carriers. It was observed that the IgA Epstein-Barr nuclear antigen 1 (EBNA1), IgA early antigen (EA)-p138 and IgG EA-p138 antibodies represent the most specific anti-EBV responses in either young or older patients with nasopharyngeal carcinoma which yield higher positive rates compared to the three control groups. Since the IgA EBNA1 response showed the highest sensitivity value for the detection of nasopharyngeal carcinoma, a novel enzyme-linked immunosorbent assay (ELISA) was established using a GST-EBNA1 protein expressed in bacteria, containing the P-threonine EBNA1 subtype cloned from DNA EBV sequence of C15 xenograft cells. Detection rates were 85.7% and 94.9% in young and older patients with nasopharyngeal carcinoma respectively, while only 3.6%, 11.1%, and 16.6% in healthy EBV carriers, patients with lymphoma and patients with autoimmune diseases, respectively. Thus, IgA EBNA1 ELISA may be useful for early diagnosis and mass screening of nasopharyngeal carcinoma in Tunisia even in young patients.

Screening of nasopharyngeal carcinoma by serology and nasopharyngoscopy and treatment outcome in endemic region

6029 Background: To study the incidence and treatment outcome of nasopharyngeal carcinoma (NPC) detected by serology and nasopharyngoscopy in endemic region. Methods: A prospective screening program for NPC using Epstein-Barr virus-specific viral capsid antigen IgA antibody level and nasopharyngoscopy was carried out in Southern China from 1996 to 2002. Subjects without NPC at the time of enrollment were followed-up annually by serology and clinical examination irrespective of their serology status. Subjects diagnosed to have NPC at the time of enrollment or during follow-up received conventional radiotherapy using megavoltage photon. Results: A total of 42,048 adults in Zhongshan city of China were enrolled into the screening program. About 7.4% had elevated IgA titre at the time of enrollment. NPC was diagnosed at first screening in 40 subjects and during follow-up in 131 subjects. Among the 171 NPC patients, 74 were asymptomatic and the disease was detected by the screening procedures, whereas the disease was detected in 97 following onset of symptoms. Stage distribution in those diagnosed by screening program was 59.5% stage I, 8.1% stage II, 21.6% stage III, and 10.8% stage IV. The corresponding stage distribution in subjects diagnosed after onset of symptoms was 7.2%, 12.4%, 39.2%, and 41.2%. In all NPC patients the IgA titre was found elevated and there was a serologic window in which the raised titre preceded the diagnosis of NPC for a period of up to 10 years. The median interval of this serologic window was 29 months in patients with stage I NPC and 39 months in those with stage II-IV disease. The 5-year disease-specific survival rate was 90% for stage I disease, 56% for stage II, 48% for stage III, and 52% for stage IV. Conclusions: Screening by serology and nasopharyngoscopy leads to the early diagnosis of NPC in endemic region with a high survival rate after treatment for stage I disease. In view of the rapid transition of disease from stage I to more advanced stage, a screening interval shorter than 10 months is recommended for subjects entering the serologic window. No significant financial relationships to disclose.

Nasopharyngeal carcinoma at the National Institute of Oncology

e17055 Background: To evaluate the disease characteristics and outcome of patients with nasopharyngeal carcinoma treated at the National Institute of Oncology (NIO) Rabat, Morocco. Methods: Between 1999 and 2001, 468 patients with a diagnosis of nasopharyngeal carcinoma were treated at the NIO. The median age was 42 years (range 10 to 83). The male/female ratio was 2.5/1. Of the 468 patients, 88 (19%), and 380 (81%) had T1-T2, and T3- T4 (TNM International Union Against Cancer staging system, 1997), respectively. Ninety percent presented with nodal metastasis. 163 patients (35%) had lymph nodes &gt;6 cm, and 229 (49%) had bilateral nodes at presentation. Histologically, 405 patients (86%) had undifferentiated carcinoma. Seventy-six percent received neoadjuvant multiagent chemotherapy containing cisplatin, followed by radiotherapy (RT). Results: After a median follow-up of 26 months, the disease-free survival (DFS) and overall survival (OS) rate for the entire group was 27% and 41%, respectively. Kaplan-Meier curves were used for evaluation of prognostic factors and were compared using the log-rank test. Nodal status had a significant impact on OS (p &lt; 0.001). Complete responders to chemotherapy had superior DFS and OS. Conclusions: Combined modality management using chemotherapy and RT resulted in satisfactory locoregional control and OS in patients with nasopharyngeal carcinoma. Nodal involvement and response to chemotherapy were important prognostic factors. No significant financial relationships to disclose.

Visual Loss Secondary to Orbital Apex Invasion as the First Manifestation of Recurrent Nasopharyngeal Carcinoma

A 51-year-old white man was referred for evaluation of visual loss in the right eye caused by an apical orbital lesion. His medical history was positive for "lymphoepithelial carcinoma" of the nasopharynx successfully treated with radiotherapy 6 years previously. Cranial CT showed a diffuse orbital mass extending from the pterygopalatine fossa, infiltrating the inferior orbital fissure, the orbital apex, and the cranial cavity. Results from an incisional biopsy of the lesion were consistent with the diagnosis of nasopharyngeal carcinoma, nonkeratinizing lymphoepithelial variant of squamous cell carcinoma. The patient underwent stereotactic radiosurgery, which arrested the tumor progression. Orbitocranial recurrence of nasopharyngeal carcinoma is rare and ocular symptoms may be the first manifestation of the disease.

Independent Effect of EBV and Cigarette Smoking on Nasopharyngeal Carcinoma: A 20-Year Follow-Up Study on 9,622 Males without Family History in Taiwan

This study aimed to assess independent effects of EBV and cigarette smoking on nasopharyngeal carcinoma, which have never been assessed in long-term follow-up studies. A cohort of 9,622 men was enrolled from 1984 to 1986. Blood samples collected at study entry were tested for antibodies against EBV antigens (anti-EBV) viral capsid antigen immunoglobulin A and DNase. The cigarette smoking habit was inquired through questionnaire interview. Newly developed nasopharyngeal carcinoma cases were ascertained through computerized linkage with national cancer registry profile. Cox's proportional hazard regression analysis was used to estimate multivariate-adjusted hazard ratio with its 95% confidence interval (95% CI). During the follow-up of 173,706 person-years, 32 pathologically confirmed nasopharyngeal carcinoma cases were identified >1 year after recruitment. Increasing serum levels of anti-EBV viral capsid antigen immunoglobulin A and DNase were significantly associated with nasopharyngeal carcinoma risk in a dose-response relationship. The multivariate-adjusted hazard ratio (95% CI) of developing nasopharyngeal carcinoma for low and high antibody levels compared with seronegatives was 9.5 (2.2-40.1) and 21.4 (2.8-161.7), respectively, for anti-EBV viral capsid antigen immunoglobulin A (P < 0.001 for trend), and 1.6 (0.5-4.6) and 16.0 (5.4-47.1), respectively, for anti-EBV DNase (P < 0.001 for trend). The shorter the time interval between study entry and nasopharyngeal carcinoma diagnosis, the higher was the proportion of anti-EBV viral capsid antigen immunoglobulin A among nasopharyngeal carcinoma patients. The multivariate-adjusted hazard ratio (95% CI) was 3.0 (1.3-7.2) for > or =30 pack-years of cumulative cigarette smoking compared with <30 pack-years as the reference. The longer and heavier the cigarette smoking habit, the higher was the nasopharyngeal carcinoma risk. Anti-EBV viral capsid antigen immunoglobulin A, anti-EBV DNase, and long-term heavy cigarette smoking are independent nasopharyngeal carcinoma risk predictors.

Evaluation of Antibodies against Different Epstein-Barr Virus Nuclear Antigen 1 Peptides in Diagnosis of Nasopharyngeal Carcinoma

Epstein-Barr virus nuclear antigen 1 (EBNA1) is a protein expressed consistently in nasopharyngeal carcinoma (NPC). Although antibody levels against three different EBNA1 peptides were all high in NPC patients, the correlation between any two biomarkers was low. Therefore, the selection of distinct EBNA1 peptides could render different results in serological detection for individuals with NPC.

Proteomic analysis of the stroma-related proteins in nasopharyngeal carcinoma and normal nasopharyngeal epithelial tissues

The stroma surrounding cancer cell population is increasingly recognized as playing an important role in cancer proliferation, invasion, and metastasis. To identify the stromal proteins involved in nasopharyngeal carcinoma (NPC) carcinogenesis, differences in protein expression of the stroma from NPC and normal nasopharyngeal epithelium tissues (NNET) were assessed using a comparative proteomic approach combined with laser capture microdissection (LCM). LCM was performed to purify stromal cells from NPC and NNET, respectively. Proteins between the pooled microdissected tumor and normal stroma were separated by two-dimensional electrophoresis (2-DE) and differential proteins were identified by mass spectrometry (MS). Sixty differential proteins between normal stroma (NS) and tumor stroma (TS) were identified, and the expression of CapG protein was further confirmed by western blotting and immunohistochemical analysis. Our results will be helpful to study the role of stroma in the NPC carcinogenesis and may provide helpful clues for pathogenesis, early diagnosis, and progression of NPC.

How reliable is contact endoscopy of the nasopharynx in patients with nasopharyngeal cancer?

To evaluate diagnostic reliability of contact rhinoscopy in patients with nasopharyngeal carcinoma. A cross-sectional randomized single-blinded study was carried out to evaluate the reliability of the findings of contact rhinoscopy in patients with nasopharyngeal carcinoma assessed by different observers. Random images of contact endoscopy of 157 subjects including normal patients and patients with nasopharyngeal carcinoma, both prior to external beam radiation therapy (RT), the non-RT group, and after external beam radiation therapy, the post-RT group, were available for analysis. Three independent observers of varying clinical experience and histopathologic knowledge viewed the images and made a diagnosis for each image. The diagnosis of each image was correlated with the histology of the biopsy from the corresponding patient. In the non-RT group, Kappa values for inter- and intraobserver reliability to differentiate normal epithelium from primary nasopharyngeal carcinoma were 0.894, 1.000, 0.794 and 0.694, 1.000, 0.776 for the house officer, radiologist, and pathologist, respectively. There were no significant differences in interobserver and intraobserver reliabilities between the assessors. In the post-RT group, Kappa values for the inter- and intraobserver reliability to diagnose recurrent carcinoma or atypia, squamous metaplasia, and radiation change for the three observers were 0.820, 0.718, 0.775 and 0.731, 0.622, 0.734, respectively. There were no significant differences in interobserver and intraobserver reliabilities between the assessors. The clinical diagnosis of nasopharyngeal carcinoma by contact endoscopy is highly reliable and is not dependent on the clinical experience or knowledge of histopathology of the observers.

Alteration of gene expression during nasopharyngeal carcinogenesis revealed by oligonucleotide microarray after microdissection of tumor tissue and normal epithelia from nasopharynx

Background Microarray and microdissection techniques were being used for many applications to study the carcinogenesis of some human tumors. But seldom studies had hitherto combined these two techniques to study carcinogenesis mechanism of nasopharyngeal carcinoma (NPC). To identify a set of genes involved in the carcinogenesis and development of NPC, we used the microdissected homogeneous NPC tissue cells and the pure normal epithelium pillar cells to construct the whole human genome expression profiles. Methods We preserved the tissue samples from nasopharynx of 18 patients (including 13 samples of NPC and 5 samples of normal or inflammatory mucous tissue samples from nasopharynx) in RNAIater Stabilization Reagent. The tissue samples were microdissected to harvest the homogeneous tissue cells, then total RNA was isolated from them. The sufficient antisense RNA (aRNA) was amplified from these total RNA. HG-U133.Plus.2.0 GeneChip was used to construct the human whole genome expression profiling of each sample. Differential patterns of expression of genes correlated with the carcinogenesis, classification and progression of NPC were identified with comparing the expression profiling data respectively in leave one out cross-validation analysis. Correlation between aRNA expression measured by the microarrays and semi-quantitative reverse transcription polymerase chain reaction (sqRT-PCR) were also ascertained, and found that hybridization results were validated in all of the 18 patients. Results Differential patterns of expression of 127 genes correlated with the carcinogenesis (A P value less than 0.001 with the 2-fold differentiated expression between case group and control group) of the NPC were filtered. The top most up-regulated and down-regulated 8 genes by the way of permutation test were also selected and listed in the paper. Expression of genes E2F6 and TSPAN-1 was identified using aRNA by sqRT-PCR and showed that there was significant difference between the average value of case groups and that of control group respectively (t=2.170, df=16, P=0.045 and t=-2.946, df=16, P=0.009). Conclusions We had identified some genes which could be the molecular marker during the carcinogenesis and the development of the NPC. The genes which selected from the different subgroups seemed to be implicated for the diagnosis,classification, and progression of NPC, and provided important insights into their underlying biology.