Advances in nasopharyngeal carcinoma

Prognostic factors for survival of patients with nasopharyngeal carcinoma following conventional fractionation radiotherapy

This study aimed to investigate the risk factors influencing the prognosis of patients receiving conventional fractionation radiotherapy. A retrospective analysis of clinical data from 100 patients with nasopharyngeal carcinoma receiving radiotherapy was conducted. The Chi-square test was used to screen the relevant factors and Cox multiple-factor analysis was used to investigate the risk factors influencing the survival of patients. One-factor analysis results revealed that tumor stage, tumor diameter, prescription dose completion and radiotherapy regularity are related to the prognosis of nasopharyngeal carcinoma and multiple-factor analysis results revealed that tumor stage, radiotherapy dose and radiotherapy regularity are independent risk factors influencing prognosis. The prognosis of patients with nasopharyngeal carcinoma receiving radiotherapy is related to tumor progression and an adequate dose of regular radiotherapy improves the prognosis of patients.

A prospective study on therapeutic gain by concurrent chemoradiotherapy for stage II-IV a nasopharyngeal carcinoma

The benefit achieved by concurrent chemoradiotherapy (CCR) and sequential chemoradiotherapy (SCR) vs radiotherapy (RT) alone for patients with stage II-IVa nasopharyngeal carcinoma (NPC) was compared. A total of 113 patients with stage II-IV a NPC were allotted into CCR group (n=38), SCR group (n=36) and RT alone group (n=39). All patients were irradiated with the same RT technique to ≥66 Gy at 2 Gy per fraction, conventional 5 fractions/week in all groups. The CCR group received concurrent chemotherapy of weekly cisplatin for 7 weeks, and the SCR group received neoadjuvant and (or) adjuvant chemotherapy. The results showed that the 3- and 5-year overall survival rate was significantly higher in CCR group than in RT alone group (92.16% vs 61.54%, 81.58% vs 51.28%, P<0.005). The median survival time was significantly longer in CCR group than in RT alone group (67.8 months vs 52.7 months, P<0.005). It was concluded that CCR could significantly improve overall survival rate, progression-free survival rate, and median survival time when compared with RT alone.

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.

Promoter methylation inhibits BRD7 expression in human nasopharyngeal carcinoma cells

BACKGROUND

Nasopharyngeal carcinoma (NPC) is a head and neck malignancy with high occurrence in South-East Asia and Southern China. Recent findings suggest that epigenetic inactivation of multiple tumor suppressor genes plays an important role in the tumourigenesis of NPC. BRD7 is a NPC-associated bromodomain gene that exhibits a much higher-level of mRNA expression in normal than in NPC biopsies and cell lines. In this study, we explored the role of DNA methylation in regulation of BRD7 transcription.

METHODS

The presence of CpG islands within BRD7 promoter was predicted by EMBOSS CpGplot and Softberry CpGFinder, respectively. Nested methylation-specific PCR and RT-PCR were employed to detect the methylation status of BRD7 promoter and the mRNA expression of BRD7 gene in tumor cell lines as well as clinical samples. Electrophoretic mobility shift assays (EMSA) and luciferase assay were used to detect the effects of cytosine methylation on the nuclear protein binding to BRD7 promoter.

RESULTS

We found that DNA methylation suppresses BRD7 expression in NPC cells. In vitro DNA methylation in NPC cells silenced BRD7 promoter activity and inhibited the binding of the nuclear protein (possibly Sp1) to Sp1 binding sites in the BRD7 promoter. In contrast, inhibition of DNA methylation augments induction of endogenous BRD7 mRNA in NPC cells. We also found that methylation frequency of BRD7 promoter is much higher in the tumor and matched blood samples from NPC patients than in the blood samples from normal individuals.

CONCLUSION

BRD7 promoter demethylation is a prerequisite for high level induction of BRD7 gene expression. DNA methylation of BRD7 promoter might serve as a diagnostic marker in NPC.

Treatment outcome of cisplatin-based concurrent chemoradiotherapy in the patients with locally advanced nasopharyngeal cancer

PURPOSE

The standard treatment of locally advanced nasopharyngeal cancer is a concurrent chemoradiotherapy (CCRT), and cisplatin has been used as the most popular chemotherapeutic agent. But many different doses and schedules for cisplatin administration such as daily, weekly and 3 week cycles have been proposed. We compared and analyzed the tumor response, the overall survival, the toxicity and the chemotherapy dose intensity in the patients with locally advanced nasopharyngeal cancer who were treated with CCRT.

MATERIALS AND METHODS

We performed a retrospective study on 55 patients with locally advanced nasopharyngeal cancer, and they were treated with CCRT as a front-line treatment from Jan 1996 to Jun 2007 at Kangnam Saint Mary's Hospital.

RESULTS

The patients had a median age of 53 years (range: 19 approximately 75 years). Of the total 55 patients, a 3-week cycle of 100mg cisplatin was administered in 31 patients and 30 mg weekly cisplatin was administered in 24 patients combined with radiotherapy. Twenty one patients had a complete response and four patients had a partial response for a response rate of 71.4% (95% CI: 59.5 approximately 83.3) after CCRT and followed by adjuvant chemotherapy. The complete response rates for the 30 mg and 100 mg cisplatin groups were 72.7% (95% CI: 54.9 approximately 90.5) and 54.2% (95% CI: 36.7 approximately 71.7), respectively (p=0.23). The duration of CCRT in the 100mg cisplatin group was significantly longer than that of the 30mg cisplatin group (11.1+/-2.9 weeks vs. 9.0+/-1.2 weeks, p=0.003). The major deviation group, which was defined as prolongation of the radiotherapy duration for more than 2 weeks, had a significantly lower objective response rate than did the non-deviation group (56.3% vs 84.2%, respectively, p=0.002). The major severe toxicities were leucopenia (49.1%), pharyngoesophagitis (49.1%), anorexia (43.6%), nausea (41.8%) and vomiting (40%).

CONCLUSIONS

Weekly 30mg cisplatin-based CCRT is a practical, feasible cisplatin schedule for the patients with locally advanced nasopharyngeal cancer in regard to decreasing the interruption of radiation treatment and decreasing the treatment-related acute toxicities.

Advances in nasopharyngeal carcinoma

PURPOSE OF REVIEW

Nasopharyngeal carcinoma prognosis is related to its potential locoregional invasion and metastatic spread. Among prognostic factors, initial tumor-node-metastasis stage is the main one, besides other biological parameters. Worldwide development of positron emission tomography imaging is changing modalities of staging. Concomitant chemoradiotherapy represents one of the most recent advances in the treatment of nasopharyngeal carcinoma patients, besides intensity-modulated radiation therapy. This review updates these recent advances in diagnosis and treatment of nasopharyngeal carcinoma.

RECENT FINDINGS

Recent publications have shown the superiority of fused positron emission tomography/computed tomography over positron emission tomography alone and conventional imaging to do an accurate staging and to impact on patient management. Circulating Epstein-Barr virus DNA load may be a useful prognostic marker in endemic regions. Recent meta-analysis confirmed the superiority of concurrent chemoradiotherapy to radiotherapy alone. Previous publications have shown that induction chemotherapy with new agents might be promising. Data demonstrating targeted therapies efficacy in metastatic nasopharyngeal carcinoma are limited to date.

SUMMARY

Positron emission tomography-computed tomography is replacing conventional imaging in the initial M staging of nasopharyngeal carcinoma. Its usefulness in response evaluation after therapy and its place in the follow-up need to be prospectively evaluated. Cisplatin-based concomitant chemoradiotherapy is now the standard treatment for locally advanced patients. However, incidence of relapses remains high, and new multimodal therapy is needed.

Nasopharyngeal carcinoma: the role of magnetic resonance imaging in diagnosis, staging, treatment, and follow-up

Nasopharyngeal carcinoma (NPC) is a distinct entity from pharyngeal squamous cell carcinoma (SCCa). Nasopharyngeal carcinoma has a unique histological appearance; has different inciting factors to SCCa; and has unique familial, genetic, and geographic predispositions. Nasopharyngeal carcinoma also has a different pathological behavior to pharyngeal SCCa, with a tendency for clival invasion, intracranial spread, and early systemic metastasis. In keeping with this distinct pathological behavior, NPC has particular imaging manifestations and staging criteria that differ significantly from pharyngeal SCCa. These features are typically much better evaluated with magnetic resonance imaging than with computed tomography. This article presents the current clinical and epidemiological background of NPC with specific reference to the role of magnetic resonance imaging in all stages of patient management, from diagnosis and staging of NPC to the role of the radiologist in treatment planning and follow-up imaging evaluation.