Les carcinomes du nasopharynx : données actuelles

[Therapeutic outcomes of nasopharyngeal carcinomas: a single-center study conducted at the Fattouma Bourguiba University Hospital in Monastir, Tunisia]

Introduction

les carcinomes nasopharyngés (CNP) sont relativement fréquents dans le pourtour méditerranéen. La survie a été largement améliorée avec les nouvelles techniques d´irradiation et les nouvelles molécules de chimiothérapie. L´objectif de notre étude est d´analyser les résultats thérapeutiques et décrire les facteurs pronostiques des CNP.

Méthodes

il s´agit d´une étude rétrospective menée entre janvier 1995 et décembre 2014, des observations de patients traités et suivis dans notre service pour un carcinome du nasopharynx. Le recueil des données a été réalisé à partir d´une fiche type. L´analyse statistique a été réalisée à l´aide du logiciel SPSS. La survie a été calculée selon la méthode de Kaplan-Meier.

Résultats

soixante-treize cas de CNP ont été colligés. L´âge moyen était de 48 ans. Une prédominance masculine a été notée. La majorité des tumeurs (56%) étaient localement avancées (T3-T4). Après un recul moyen de 45,5 mois, le taux de récidives locorégionales était de 19,4%. Trois patients (4%) ont présenté des métastases osseuses. La survie globale à 5 ans était de 65%. Les facteurs influençant positivement la survie globale à l´analyse étaient le stade TNM précoce et le fractionnement de 1,8 Grays/séance de la radiothérapie. Les taux de récidives locales et ganglionnaires étaient respectivement de 13,8% et 5,5%, essentiellement pour des tumeurs classées T4 N2. Les séquelles thérapeutiques étaient dominées par les otites séromuqueuses (42,7%), le trismus (38,7%) et la xérostomie (32%).

Conclusion

la survie globale des CNP s´est améliorée particulièrement avec l´avènement de la radio-chimiothérapie concomitante. Néanmoins, la toxicité tardive invalidante demeure non négligeable. Les facteurs de bon pronostic retrouvés dans cette étude étaient le stade tumoral précoce ainsi que la modalité de fractionnement de la radiothérapie.

Nasopharyngeal carcinoma with cutaneous metastases

INTRODUCTION

Cutaneous metastases from nasopharyngeal carcinoma are extremely rare and associated with a poor prognosis.

CASE REPORTS

We retrospectively reviewed 820 patients with nasopharyngeal carcinoma treated over a 20-year period in the radiotherapy department of Farhat Hached hospital in Sousse and Ibn Khaldoun Medical centre, Hammam Sousse. Two of these patients presented cutaneous metastases. The skin lesions appeared during radiotherapy and 3 months after treatment of the primary tumour. Cutaneous metastases present as multiple painless nodules and erythematous plaques. Cutaneous metastases were associated with other metastatic sites (liver, bone). One patient received chemotherapy. Both patients died in a context of rapidly progressive disease.

DISCUSSION

Nasopharyngeal carcinoma with cutaneous metastases is a rapidly fatal disease. In the light of these two cases and a review of the literature, patients with this disease are aged between 30 and 63 years with a marked male predominance. Cutaneous metastases are correlated with a more advanced primary tumour. The main sites are the trunk and scalp. There is no standard treatment modality for this disease and survival does not exceed 9 months.

[Metastatic nasopharynx cancer at diagnosis: clinical and prognostic (study of 51 cases)]

L’objectif de cette étude rétrospective était de détailler les différents aspects épidémiologiques, cliniques, thérapeutiques et pronostiques du cancer du cavum d'emblée métastatique dans le centre Tunisien. Il s’agit d’une étude portant sur 51 patients atteints d’un cancer du nasopharynx (CNP) histologiquement prouvé et métastatique d’emblée, soit au moment du diagnostic , colligés dans les services ORL du CHU Farhat Hached de Sousse et les services de radiothérapie du centre tunisien, à savoir du CHU Farhat Hached de Sousse, et du centre médical Ibn Khaldoun de Hammam Sousse, entre Janvier 1995 et Décembre 2010. Cinquante et un patients atteints de cancer du nasopharnx, d’emblée métastatiques ont été recensés. L’âge moyen était de 49 ans. Le Sex-Ratio était de 6,2. Les métastases osseuses étaient les plus fréquentes (94,1%), suivies par les métastases hépatiques (34,6%). Sur le plan thérapeutique, la majorité de nos patients a reçu une chimiothérapie (41 patients), dont 31 en association avec une radiothérapie. Le protocole adriamycine et cisplatine a été le plus fréquemment utilisé (92,6%). Vingt patients ont eu une radiothérapie cervicofaciale à intention curative (doses ≤ 70 Gy), quatorze autres patients ont reçu au niveau du cavum une radiothérapie à visée symptomatique ( doses de 30Gy en 10 séances) associée à une irradiation des sites métastatiques dans 9 cas. Les survies globales à 2 ans et à 5 ans étaient respectivement de 29% et de 10%. Au stade de métastases inaugurales, le cancer du cavum est une maladie grave, rapidement mortelle malgré les avancées thérapeutiques. Au vue des données de notre étude et de celles de la littérature, la chimiothérapie à base de cisplatine et la radiothérapie cervico-faciale à doses curatives et celle des métastases a permis d’obtenir de longues survies et même des réponses complètes. Les futurs essais pourraient tester de nouvelles molécules en vue d'une intensification thérapeutique.

Usefulness of IGF-1 serum levels as diagnostic marker of nasopharyngeal carcinoma

BACKGROUND

The role of IGF-1 in promoting cancer has been investigated for many years. The aim of this study is to explore the relationship between rates of IGF-1 and NPC and to evaluate association of IGF-1 with clinical parameters.

MATERIALS AND METHODS

IGF-1 levels was measured by Elisa test among 82 NPC patients and 60 healthy controls

RESULTS

Our results showed, for the first time, a significant increased levels of IGF-I in NPC by in comparison with healthy controls (p<0.01). According to the age, sex and tumor size of NPC patients, we demonstrated that IGF-1 concentrations are significantly higher in NPC aged over 30 years compared to patients aged less than 30 years (p<0.01). The IGF-1 levels are, also, higher among women compared to men (p<0.01). The concentrations of IGF-1 were positively correlated with tumor size of NPC patients (p<0.01).

CONCLUSION

IGF-I could be a good nasopharyngeal cancer diagnostic marker.

Are HLA-E*0103 alleles predictive markers for nasopharyngeal cancer risk?

BACKGROUND

Nasopharyngeal carcinoma (NPC) is a particular entity of head neck cancer, tightly related to Epstein-Barr virus infection and thus to HLA genes. In this study, we aimed to analyze HLA-E polymorphism in NPC advent and prognosis. 130 unrelated patients with CNP and 180 unrelated and healthy controls were included in our study. HLA-E genotyping was performed by PCR/RFLP method; SPSS (13.0) was used for statistical analysis, and survival curbs were established with the "Kaplan-Meier" method (Log Rank<0.05).

RESULTS

We found a significant difference within HLA-E*103 variants between patients and controls: E*1031 and E*1032 were associated with CNP (OR=1.613, p=0.013 and OR=1.0809, p=0.055), and E*1033 with controls (OR=0.254, p<10(-4)).

CONCLUSION

Our study reveals that HLA-E polymorphism is associated with nasopharyngeal cancer. HLA-E expression studies could be used to understand the implication of E*103 variants.

[Genetic polymorphism of cytochrome P450 2E1 and the risk of nasopharyngeal carcinoma]

Cytochrome P450 2E1 (CYP2E1) is a detoxifying enzyme that belongs to the phase I metabolism of xenobiotics. This enzyme is encoded by a highly polymorphic gene whose common polymorphism corresponds to the substitution of cytosine (C) and thymine (T) at position -1019 (rs2031920). This polymorphism has been identified in several cancers including nasopharyngeal cancer (NPC). The study involved 124 patients with nasopharyngeal carcinoma, compared with 166 healthy controls. The presence or absence of the polymorphism is determined by PCR-RFLP. The frequency comparison between the two groups is determined by the χ(2) test. The analysis of our results showed a significant difference between the two groups regarding the mutant genotype (C2/C2) (5% vs. 0.5%, P=0.04) and has a risk factor for NPC in Tunisia (OR=8.39; CI 95% [0.99-388.1]). Also, the C2 allele was significantly associated with the group of patients than the control group (6% vs. 2%, P=0.016) and increased three times the risk of NPC in Tunisia (OR=2.99, CI 95% [1.12-8.79]). Our results confirm the results reported in other populations and emphasize the importance of the involvement of this gene in the development of detoxification of the NPC, which seems more and more strongly associated with environmental factors.

[Update on medical therapies of nasopharyngeal carcinomas]

Nasopharyngeal carcinomas (NPC) are predominantly of undifferentiated type (UCNT or undifferentiated carcinoma of nasopharyngeal type), rare (<1/100,000) and sporadic in occidental countries, but endemic in the Mediterranean area of intermediate incidence (2 to 10/100,000) and highly frequent (>10/100,000) in South East Asia. NPC staging is based on TNM UICC 2002 that has a prognostic and therapeutic orientation impact. Irradiation of the primitive tumor and its extensions remains the standard loco-regional treatment. The recent introduction of primary and concomitant chemotherapy leads to an improvement in terms of overall and disease-free survival, specially for for high-risk-patients (T3-4 and N2-3 disease). Prognosis remain linked to T, N, histologic type and quality of response to chemotherapy and radiotherapy.

Nasopharyngeal carcinoma in a south European population: epidemiological data and clinical aspects in Portugal

The incidence of nasopharyngeal carcinoma (NPC) varies worldwide, with higher rates in southern Asia, intermediate rates in Mediterranean basin countries as well as in Greenland and Alaska populations, and low rates in most of the western countries. The percentage of NPC types seems to vary according to the WHO classification. Portugal is also a Mediterranean basin country. The NPC patterns in Portuguese population is comparatively analyzed with a review of the related literature, concerning the overall incidence, male/female ratio, age of incidence, WHO type frequency, Epstein-Barr virus relationship and genetic susceptibility. The particular findings in the Portuguese population can be discussed in the light of genetic background and close relationships with potential exogenous oncogenic factors.

HLA association with nasopharyngeal carcinoma in southern Tunisia

In order to study the association of HLA-A, -B and/or DRB1, DQB1 and the nasopharyngeal carcinoma (NPC), 141 patients affected with NPC were typed for the HLA class I by serology method of microlymphocytotoxicity. Among these patients 101 were genotyped for HLA class II system by the PCR-SSP technique. HLA typing results were compared to those of 116 controls. We found that the HLA-A31 and -A33 antigens were significantly more expressed in patients than in the controls (P = 0.016 and 0.010, respectively) and the HLA-A19 antigen, was significantly more frequent in patients when compared to the controls (P = 0.007). The HLA-DRB1*03 and DRB1*13 alleles were significantly more frequent in patients as compared to the controls. The DRB1*01 allele was expressed with a frequency of 20.69% in the controls whereas it was only detected in 3.96% of the NPC patients. Furthermore, the DQB1*05 allele was expressed at a frequency which was significantly less important in affected patient (P = 0.03), whereas, the DQB1*02 allele was more frequent in patients (P = 0.643 x 10(-4)). Thus our study revealed a significant increase of HLA-A31, A33, A19, B16, B53 and DRB1*03, DRB1*13 and DQB1*02 alleles in our patients. These markers could play a predisposing role in the development of NPC. In contrast, a decrease of HLA-B14, -B35 and DRB1*01 and DQB1*05 alleles was found suggesting a likely protective effect.

Autoantibodies as potential biomarkers for nasopharyngeal carcinoma

Autoantibody signatures, as new biomarkers, may improve the early detection of nasopharyngeal carcinoma (NPC). We constructed a T7 phage cDNA library from mixed NPC tissues, and we isolated 31 tumor-associated proteins using biopan enrichment techniques with sera from NPC patients and from healthy population. DNA sequence analysis showed that among 31 phage-displayed proteins, 22 have sequence identity with known or putative tumor-associated proteins. The results of immunochemical reactivity of patients' sera with phage-expressed proteins showed enrichment in the number of immunogenic phage clones in the biopanning process and also confirmed that antibodies were present in the sera of patients but not in the sera of healthy donors. The autoantibody against phage-expressed protein MAGE, HSP70, Fibronectin, and CD44 measured by ELISA had greater predictive value than that against EBNA-1, respectively. The antibody levels against MAGE in sera positively correlated with the clinical stages of NPC, and the antibody levels against other three proteins partly correlated with the clinical stages of NPC. Our studies suggested that the autoantibodies against tumor-associated antigens in the sera of NPC patients could be used as a screening test for NPC. Studies of the corresponding proteins may have significances in tumor biology, novel drug development, and immunotherapy.

Investigation of allelic imbalances on chromosome 3p in nasopharyngeal carcinoma in Tunisia: high frequency of microsatellite instability in patients with early-onset of the disease

Tunisia is one of the world's intermediate risk areas for nasopharyngeal carcinoma (NPC). Loss of heterozygosity (LOH) on the short arm of chromosome 3 (3p) is the most frequent genetic change reported in NPC from endemic areas. In the present study, we investigate the incidence of LOH and microsatellite instability (MSI) on chromosome 3p in 49 microdissected primary NPC specimens and corresponding non-cancerous tissues from Tunisian patients using six microsatellite polymorphic markers. LOH at one or more markers was observed in 40 out of 48 informative cases (83.3%). The markers D3S1038 at 3p25.2-26.1 and D3S1076 at 3p21.1-21.2 have showed the highest frequency of LOH (51.3%), followed by D3S1067 at 3p14.3-21.1 (48.7%), D3S1568 at 3p21.3 (47.4%), D3S659 at 3p13 (15.3%), and D3S1228 at 3p14.1-14.2 (11%). Interestingly, MSI at one or more microsatellite markers was observed in 15 cases (31.2%). The highest frequency of MSI was presented by D3S1568 (18.4%), D3S1067 (17.9%), and D3S1038 (12.8%). With regard to clinicopathological features, LOH was found to be less common in young patients (under 25 years) than in adults (p=0.04), whereas MSI was found to be more frequent in patients under 45 years than in older patients (p=0.006). No significant correlation was found between LOH or MSI and the other clinicopathological features investigated including, gender, tumor size, lymph node metastasis, UICC clinical stage, and histological subtype. This study revealed different patterns of allelic imbalance on chromosome 3P in NPC between age groups in Tunisia, and suggests an alteration in the DNA mismatch repair machinery that may be, in part, responsible of the early age onset form of this disease in North African populations. More attention should be given to the mismatch repair system in the juvenile form of this disease in future studies.

Polymorphism analysis of Epstein-Barr virus isolates of nasopharyngeal carcinoma biopsies from Tunisian patients

Many studies suggest that the focal distribution of nasopharyngeal carcinoma (NPC) may be influenced not only by host genetics, diet and environments but also by interplay with Epstein-Barr virus (EBV) genetics. Specific EBV gene variants (the A and C types, the BamHI f configuration, a C terminal 30 bp deletion and a N terminal loss of an XhoI site in the BNLF1 gene) have been explored in high incidence areas in southern Asian NPC patients. In contrast, in Tunisia where NPC represents the most frequent type of Head and Neck cancer the distribution of these polymorphisms remains poorly investigated. In order to characterize the epidemiology of EBV variants in Tunisian NPC patients, we have investigated the A or B type of the EBV nuclear antigen (EBNA)2 gene, the C or D type of the BamHI W1/I1 region, the F/f variants of the BamHI F region and the presence or the absence of the XhoI site, 30 bp deletion and Taq1 site in the BNLF1 gene in 47 NPC biopsies, 12 being younger than 30 and 35 older than 30. Our results show a unique genetic profile of the tumor EBV strains regarding the A and D types, the prototype F and retention of the XhoI restriction site in the N terminal region of BNLF1 gene. With regard to the C terminal region of this gene, four genetic profiles were detected: (1) the occurrence of the 30 bp deletion in association with the Taq1 site in 39 cases (83%), (2) the presence of the Taq1 site by itself in 5 cases, (3) the occurrence of the 30 bp deletion by itself in 2 cases and (4) the occurrence of a new deletion of 81 bp covering the 30 bp deletion in association with the Taq1 site in one case. With the exception of the 81 bp deletion, which has not been previously described in the literature, the summarized results have shown the same genetic profile in Tunisian NPC tumor isolates as tumor isolates from other North African and Mediterranean countries. Hence, the observed EBV polymorphisms are not fully specific of to the Tunisian NPCs. Nevertheless, the notion of a divergence between North African and Asian tumor EBV isolates is reinforced by this study.