Nasopharyngeal carcinoma. Brief review

Genomic landscape of virus-associated cancers

It has been estimated that 15%-20% of human cancers are attributable to infections, mostly by carcinogenic viruses. The incidence varies worldwide, with a majority affecting developing countries. Here, we present a comparative analysis of virus-positive and virus-negative tumors in nine cancers linked to five viruses. We find that virus-positive tumors occur more frequently in males and show geographical disparities in incidence. Genomic analysis of 1,658 tumors reveals virus-positive tumors exhibit distinct mutation signatures and driver gene mutations and possess a lower somatic mutation burden compared to virus-negative tumors of the same cancer type. For example, compared to the respective virus-negative counterparts, virus-positive cases across different cancer histologies had less often mutations of TP53 and deletions of 9p21.3/ CDKN2 A- CDKN1A ; Epstein-Barr virus-positive (EBV+) gastric cancer had more frequent mutations of EIF4A1 and ARID1A and less marked mismatch repair deficiency signatures; and EBV-positive cHL had fewer somatic genetic lesions of JAK-STAT, NF-κB, PI3K-AKT and HLA-I genes and a less pronounced activity of the aberrant somatic hypermutation signature. In cHL, we also identify germline homozygosity in HLA class I as a potential risk factor for the development of EBV-positive Hodgkin lymphoma. Finally, an analysis of clinical trials of PD-(L)1 inhibitors in four virus-associated cancers suggested an association of viral infection with higher response rate in patients receiving such treatments, which was particularly evident in gastric cancer and head and neck squamous cell carcinoma. These results illustrate the epidemiological, genetic, prognostic, and therapeutic trends across virus-associated malignancies.

Higher incidence of nasopharyngeal carcinoma in some regions in the world confers for interplay between genetic factors and external stimuli

Nasopharyngeal carcinoma (NPC) is a rare variety of head and neck cancers. The risk factors include three major causes: genetic factors, viral infection, and environmental and dietary factors. The types of NPC show strong ethnic and geographic variations. The keratinizing and non-keratinizing types are prevalent in the lower incidence regions like North America and Europe; whereas the undifferentiated type is mostly found in the regions with higher incidences like China, North Africa, Arctic, and Nagaland of North-East India. These suggest a possible major role of the internal genetic factors for generation and promotion of this disease. Viral infections might accelerate the process of carcinogenesis by helping in cellular proliferation and loss of apoptosis. Diet and other environmental factors promote these neoplastic processes and further progression of the disease occurs.

Nasopharyngeal Carcinoma: A 15 Year Study with Respect to Clinicodemography and Survival Analysis

Nasopharyngeal carcinoma (NPC) is a rare malignancy in Kashmir with distinct pattern, hence we planned to study its clinicodemographic and survival profile. Kashmir has unique lifestyle and dietary habits which may be the source of carcinogenic compounds, most likely implicated in causation of NPC. A total of 148 patients of NPC registered from January 2000 to December 2014 were analyzed. The Mean ± SD age was 45.15 ± 17.092 years (range 11-85 years). The males were 72.3 % (N = 107) with male: female ratio of 2.61:1. Most of the patients were from rural area 81.90 % (N = 95) and non-smokers were 53.44 % (N = 62). Neck swelling was commonest presentation. WHO Type III NPC was commonest histopathological diagnosis 65.3 % (N = 92). Stage IV 36.1 % (N = 51) was commonest stage followed by stage III was 32 % (N = 46). Majority of the patients of NPC received CCRT 68.7 % (N = 78) followed by SCRT 13 % (N = 15) and Induction + CCRT 13 % (N = 15). The overall mean survival of NPC was 49.56 months. There was no significant correlation of age, gender, smoking, histopathology and treatment on the overall survival. However the stage was the only strong predictor of overall survival. Also the patients with intracranial extension had low survival which is turn depicts the advanced stage of disease. NPC survival is directly related to the stage of the disease irrespective of the treatment modality received. The negative EBV status in our patients implies that there are other risk factors involved in the causation of NPC for which further studies are needed to establish the etiological insult.

Proteome analysis of antiproliferative mechanism of 12-O-tetradecanoylphorbol 13-acetate on cultured nasopharyngeal carcinoma CNE2 cells

12-O-Tetradecanoyl-phorbol-13-acetate (TPA) is a plant derivative with multiple function as tumor promoter, differentiation revulsant or leukemia therapy drug. The molecular mechanism of its function is perplexing. Many studies have focused on the mechanism of TPA stimulation in tumor promotion of mouse models or terminal differentiation of leukemia cells, but the effect of TPA on nasopharyngeal carcinoma (NPC) remains unclear, while TPA was considered to be associated with NPC development. In the present study, we employed proteomics techniques to study protein changes of a poorly differentiated squamous carcinoma cell line-CNE2 of human NPCs cells induced by TPA. Six significantly and reproducibly changed proteins were identified and their functional implications were discussed in some details.

Deaths from nasopharyngeal cancer among waiters and waitresses in Chinese restaurants

OBJECTIVE

Previous studies have shown that waiters have a high risk of developing cancers of the buccal cavity and pharynx, but nasopharyngeal cancer (NPC) has not been specifically studied. This study was carried out to investigate whether waiters/waitresses in Chinese restaurants have an increased risk of dying from NPC.

METHODS

A mortality odds ratio study was used to estimate the relative risk of dying from NPC for waiters/waitresses working in Chinese restaurants in Hong Kong during the period 1986-1995, using the general population as the external comparison group and deceased kitchen workers as an internal comparison group. Cases were deaths from NPC and the controls were deaths from the selected sets of reference causes.

RESULTS

Seventeen deaths from NPC were identified among 415 deceased waiters and four NPC deaths occurred among 140 deceased waitresses. The adjusted mortality odds ratio (aMOR) for NPC was increased among waiters, being 3.02 (95% CI 1.82-5.00) and 2.61 (95% CI 1.02-6.69) in the external and internal comparisons, respectively. For waitresses, the aMOR was 4.58 (95% CI 1.63-12.86) in the external comparison. Analysis by duration of union membership suggested a dose-response relationship.

CONCLUSIONS

An increased risk of dying from NPC was observed among waiters/waitresses and could not be fully explained by bias or confounding factors. Possible risk factors related to poor indoor air quality in the service areas of Chinese restaurants in Hong Kong should be further investigated.

Evaluation of the Effect of Radiation Therapy to Nasopharyngeal Carcinoma by Positron Emission Tomography with 2-

Purpose: This investigation evaluated the effectiveness of positron emission tomography with 2-[F-18]fluoro-2-deoxy-D-glucose (PET-FDG) in assessing residual tumor or tumor recurrence in postradiation nasopharyngeal carcinoma (NPC) patients.Procedures: Forty-six patients with histologically proven NPC who received radiotherapy were included. PET-FDG images were analyzed by a semiquantitative method, metabolic ratio (tumor to cerebellum ratio).Results: The overall sensitivity and specificity of PET-FDG to detect residual tumors and recurrent lesions in the postradiation patients were 80% (12/15) and 87% (27/31), respectively. In patients with PET-FDG 6 months after radiation therapy, the sensitivity and specificity raised to 92% (11/12) and 100% (20/20), respectively.Conclusions: PET-FDG is effective in the evaluation of NPC treated with radiation. The optimal timing in assessing residual tumor or tumor recurrence in postradiation patients should be 6 months or later.

Impact of changes in the treatment of nasopharyngeal carcinoma: an experience of 30 years

Two hundred and twenty-eight patients with nasopharyngeal carcinoma were treated in a single institution in a 31-year period. Overall survival (OS), disease-free survival (DFS), and complete response (CR) rates were analyzed. In addition, survival and control rates from 1960 to 1975 and from 1976 to 1991 were evaluated. In the latter group, a comparative study was performed between patients treated with neoadjuvant chemotherapy (NCT) before radiotherapy (RT) (45) and patients treated with radiotherapy alone (45). OS at 5 and 10 years were 42 and 34%, and DFS rates were 35 and 30%, respectively. CR was achieved in 184 patients (81%). Tumor progression and survival were strongly associated with T-category. Use of fashioned blocks, age and T-category were the most important factors influencing survival in a multivariate analysis. In the patients treated with NCT, rates of CR and OS were not significantly different when compared with the concurrent RT alone group. Ninety-nine patients had recurrence (54%) and 58 received rescue treatment. Modern radiotherapy techniques have greatly assisted in the improvement of tumor control rates. Chemotherapy must be further evaluated and new treatments for relapsed patients are needed.

Preserved foods and nasopharyngeal carcinoma: a case-control study among Singapore Chinese

The association between the consumption of preserved foods in infancy, childhood and adulthood and the risk of nasopharyngeal carcinoma was investigated in a case-control study among Singapore Chinese: 200 cases (73% male) were compared with 406 hospital controls (71% male). Significantly increased risks were observed in association with frequent adult consumption of salted soy beans (OR 7.3 for consumption 4 or more times per week, compared with never), canned pickled vegetables (p = 0.01; OR 4.5 for 4 or more times per week), "sze chuan chye", a salted Chinese tuber, (OR 2.4 for 4 or more times per month) and "kiam chye", salted mustard greens (OR 2.7 for 4 or more times per week). A protective effect of high vitamin-E intake in adulthood was observed (OR 0.5 for the highest third of the control range, as compared with the lowest).

Nasopharyngeal carcinoma: a 15-year retrospective study

Malignancy in the nasopharynx, although uncommon, is potentially devastating because of the anatomy of the region and benign early symptoms, which result in infrequent early diagnosis. High-dose radiation therapy, with fields including the oral structures, is the treatment of choice and may result in significant oral complications. This paper reviews 39 cases of nasopharyngeal carcinoma diagnosed at the University of North Carolina Hospitals over a 15-year period. Patient demographics, histopathology, presenting signs and symptoms, stage at diagnosis, possible risk factors, treatment modalities, survival, side-effects of therapy, and dental intervention are reported.

Chemotherapeutic treatment of recurrent and/or metastatic nasopharyngeal carcinoma: a retrospective analysis of 40 cases

Authors carried out a review of 40 cases of recurrent and/or metastatic nasopharyngeal carcinoma (NPC) treated with cisplatin-based chemotherapy at the Division of Othorhinolaryngology and the Service of Chemotherapy of the University of Palermo between July 1984 and July 1992. All patients were treated with regimens comprising high dose cisplatin (80-100 mg m-2). Histologically there were 29 squamous cell and 11 undifferentiated NPC. Thirty-nine patients were evaluable for response and toxicity. The overall response rate was 64%, with a 20.5% complete response rate and a 43.5% partial response rate. The mean duration of complete responses was 10.2+months, while that of partial responses was 8.6+months. The mean survival of the whole group was 11.4+months, with four patients alive after 2 years of follow-up. No statistically significant difference in response rate and survival was found between patients with metastatic disease and those with locoregional recurrency, and between patients with squamous cell NPC and those with undifferentiated histology. The employed regimens have been generally well tolerated. These data confirm that NPC is a neoplasm highly responsive to chemotherapy. However, duration of objective response and survival are still largely unsatisfactory.

Detection of Epstein-Barr virus in a case of undifferentiated nasopharyngeal carcinoma by in situ hybridization with digoxigenin-labelled PCR-generated probes

A case of nasopharyngeal carcinoma is presented. Epstein-Barr viral genome was identified in the neoplastic cells by in situ hybridization with digoxigenin-labelled polymerase chain reaction-generated probes. We report the development of this technique in paraffin-embedded sections and propose that such identification may prove valuable for the diagnosis of this tumour in routine material.

Diagnosis of nasopharyngeal carcinoma by DNA amplification of tissue obtained by fine-needle aspiration

BACKGROUND

In nasopharyngeal carcinoma the primary lesion is often difficult to find. Metastatic lesions occur frequently but are difficult to distinguish from other head and neck tumors. The viral genome of the Epstein-Barr virus (EBV) can be identified in the cells of this carcinoma.

METHODS

We used the polymerase chain reaction (PCR) to test for the presence of EBV genomes in 15 samples of metastatic squamous-cell carcinoma of the neck obtained by fine-needle aspiration and in 26 samples obtained by biopsy of lymph nodes. For controls we used disease-free lymph nodes from 10 patients with various head and neck tumors, tonsillar tissue from 46 subjects, blood from 59 EBV-seropositive blood donors, and mononuclear cells from 8 patients with fatal lymphoproliferative lesions.

RESULTS

Of the 41 malignant lesions examined, only the nine nasopharyngeal carcinomas (one primary lesion and eight metastases) contained EBV genomes. None of the 20 nodes with other types of cancer, the 10 disease-free nodes, or any of the 105 normal control samples contained detectable EBV. In two patients with suspected metastases from occult primary tumors, the presence of EBV was predictive of nasopharyngeal carcinoma; in both cases overt nasopharyngeal carcinoma developed within one year.

CONCLUSIONS

In patients with suspected nasopharyngeal carcinoma, fine-needle aspiration can provide tissue for diagnosis by DNA amplification of EBV genomes. The presence of EBV in metastases from an occult primary tumor is predictive of the development of overt nasopharyngeal carcinoma.

Familial aggregation of nasopharyngeal carcinoma and other malignancies. A clinicopathologic description

Nasopharyngeal carcinoma (NPC) occurred in five members in three generations of a white American family of Scandinavian descent. Six other family members had malignancies including malignant melanoma, malignant lymphoma, squamous cell carcinoma of the tongue, adenocarcinoma of the colon, and asynchronous bilateral in situ and invasive ductal carcinomas of the breast. There was also a history of autoimmune disorders and exposure to smoke, fumes, and chemicals in some family members. Regression analysis revealed a significant covariate risk for exposure to smoking, alcohol ingestion, dust, salted or spicy foods, and poorly ventilated conditions. According to segregation analysis, the susceptibility to nasopharyngeal carcinoma and other malignancies in this family was transmitted as an autosomal codominant characteristic. A specific histocompatibility antigen (HLA) haplotype of A1-B37-DR6 was associated with a predisposition for NPC, but no linkage was identified. Laboratory studies in selected family members did not reveal significantly elevated levels of Epstein-Barr virus antibodies or serum carcinoembryonic antigen. No specific karyotypic abnormalities were identified with peripheral blood chromosome analysis. This family was an example of apparent autosomal codominant susceptibility to NPC and other malignancies. The relationship of malignancy to the HLA haplotype of A1-B37-DR6, autoimmune disorders, and cytogenetic abnormalities was intriguing but not defined clearly.

Ipsilateral craniofacial uptake of Tc-99m MDP in nasopharyngeal carcinoma: incidence and implication

A five year review of 224 Tc-99m methylene diphosphonate (MDP) scintiscans of 194 patients with proven nasopharyngeal carcinoma revealed evidence of craniofacial asymmetry in 73.7 per cent. In virtually all instances tracer accumulation corresponded to the side of the primary lesion, cervical node enlargement and or cranial nerve dysfunction. It was concluded that the high frequency of asymmetric ipsilateral MDP accumulation about the face may be attributed to one or all of the following; tumour extension into contiguous structures, localised inflammatory or necrotic changes or even tracer uptake by the tumour itself.

Carcinoma of the nasopharynx--comparison of the UICC and Ho clinical staging systems

From 1974 to 1985 definitive radiation therapy was performed in 76 patients with nasopharyngeal carcinoma (NPC). Of the 76 patients 59 presented UICC stage IV and 13 UICC stage III. The distribution of the stages was more homogeneous for the Ho system: Ho I, n = 4; II, n = 21; III, n = 16; IV, n = 32; V, n = 3. Radiotherapy followed the guidelines of the M.D. Anderson Hospital in Houston. A median dose of 68 Gy was given to the primary and of 66 Gy to the neck nodes, independent of the histologic subtype. The 5-year actuarial survival rate was 41% and the disease specific relapse-free survival (r.f.s.) 45%. Analysis according to the UICC classification and Ho's classification showed obvious deficiencies in both staging systems, but did not result in major prognostic differences. The freedom from local relapses correlated (P less than 0.05) with the T categories of the UICC at presentation (75% in T1 vs 45% in T4) and the freedom from distant metastases was significantly influenced by the cervical status (fixed cervical lymph nodes (UICC N3) vs, e.g., UICC N2: 51% vs 90%; P less than 0.05). In case of supraclavicular lymph nodes (Ho IV; Kyoto C) the freedom of distant metastases was lower than in case of upper cervical lymph nodes (58% and 79%, respectively; P = 0.3).

Case report of successful use of VP-16 in nasopharyngeal carcinoma

We report the use of VP-16 as a single agent for the treatment of nasopharyngeal carcinoma. Our patient, a 16-year-old Black Haitian male, had complete clinical and radiographic response to VP-16. The remission continued for 14 months. The patient experienced minimal toxicity. We believe that the good response, excellent compliance, and minimal toxicity experienced by our patient should encourage more trials of VP-16 as upfront therapy for patients with nasopharyngeal carcinoma.

Phorbol ester and Epstein-Barr virus dependent transformation of normal primary human skin epithelial cells

Substantial evidence has implicated Epstein-Barr virus (EBV) in the aetiology of two human neoplasms, nasopharyngeal carcinoma (NPC) and Burkitt's lymphoma. This is supported by the presence of high antibody titres to EBV early antigen and virus capsid antigen, as well as antibody to two viral-associated enzymes, DNase and DNA polymerase. Patients with NPC, particularly the undifferentiated form, are commonly found to have EBV DNA in the tumour. Ito and others have presented strong epidemiological evidence that phorbol esters are related to the unusual geographic distribution of NPC in southeastern regions of China. There appears to be a close link between the widespread EBV infection of the Asian population and the distinct regional distribution in China of plants that produce diterpene ester. Naturally occurring phorbol esters are produced by plants of the Euphorbiaceae and Thymelaeaceae, which are used as traditional herbal medicines. Although it has been established that EBV can infect epithelial cells isolated from NPC as well as certain normal epithelial cells, there has been no in vitro evidence that EBV induces neoplastic transformation in normal human epithelial cells with or without exposure to phorbol esters. We report here evidence that transformation of normal human epithelial cells results from exposure to infectious EBV and that transformation is dependent on the presence of phorbol esters.

Nasopharyngeal carcinoma: the Dana-Farber Cancer Institute experience with 24 patients treated with induction chemotherapy and radiotherapy

Nasopharyngeal carcinoma traditionally has been treated with radiotherapy alone. Although the probability of cure for patients with stage I and II nasopharyngeal carcinoma is high, the probability of cure for patients with stage III and IV disease is poor because of a higher rate of local-regional and distant failure. Between February 1981 and August 1986, 24 patients with previously untreated, stage IV nasopharyngeal carcinoma were treated with two to four monthly courses of cisplatin-based combination chemotherapy prior to radiotherapy. A response to induction chemotherapy was recorded in 75% of patients (29% complete response and 46% partial) prior to radiotherapy. By actuarial estimate with a median follow-up of 42 months, the 2-year failure-free survival for all patients was 57%. In conclusion, induction chemotherapy has significant activity in nasopharyngeal carcinoma. The toxicity of this approach, as well as the influence of initial histopathology and response to chemotherapy on survival, will be discussed.