Timing of Chemoradiotherapy and Patient Selection for Locally Advanced Nasopharyngeal Carcinoma

Combining tumor response and personalized risk assessment: Potential for adaptation of concurrent chemotherapy in locoregionally advanced nasopharyngeal carcinoma in the intensity-modulated radiotherapy era

BACKGROUND AND PURPOSE

In the intensity-modulated radiotherapy (IMRT) era, the role of concurrent chemoradiotherapy (CCRT) after induction chemotherapy (IC) in locoregionally advanced nasopharyngeal carcinoma (LANPC) is undetermined, while concerns exist about CCRT-associated excessive toxicity. We aimed to combine tumor response and risk assessment to guide decisions about concurrent chemotherapy.

MATERIALS AND METHODS

From April 2009 to December 2015, 744 LANPC patients treated with CCRT/IMRT after IC were included. Matching techniques were performed for treatment effect evaluation. Tumor response to IC was used for patient stratification. A nomogram was built based on multivariable Cox regression analysis to predict overall survival (OS).

RESULTS

After IC, 508 patients (68.3%) had favorable tumor response (complete or partial response), among whom IC + CCRT achieved significantly superior 5-year disease-free survival and OS than IC + IMRT (82.2% vs. 72.5%, P = 0.025; 89.2% vs. 79.9%, P = 0.025). However, no significant difference was found in patients with unfavorable response (both P > 0.05). For favorable responders, a nomogram was built integrating age, smoking, T category, N category, pretreatment Epstein-Barr virus DNA and treatment modality. The concordance index was 0.713 and calibration was good. The nomogram determined three risk groups with distinct OS. High-risk patients benefited from CCRT after IC regarding disease-free survival, OS and distant metastasis-free survival, whereas low- and intermediate-risk patients did not.

CONCLUSIONS

For LANPC patients with unfavorable response to IC, subsequent CCRT seems inadequate, rendering intensification necessary. For favorable responders with low risk, IC + IMRT represents a reasonable de-intensification approach, although confirmation by prospective data is needed.

Long-term follow-up of a phase III study comparing radiotherapy with or without weekly oxaliplatin for locoregionally advanced nasopharyngeal carcinoma

BACKGROUND

Previous results from our trial showed that adding oxaliplatin to radiotherapy (RT) increased survival in patients with locoregionally advanced nasopharyngeal carcinoma (NPC) at 2 years. Here, we present the data of long-term efficacy and late toxic effects.

PATIENTS AND METHODS

Between January 2001 and January 2003, 115 Patients with nonkeratinizing/undifferentiated locoregionally advanced NPC were randomly to receive either RT alone (n = 56) or plus concurrent oxaliplatin 70 mg/m(2) weekly for six cycles (n = 59).

RESULTS

After a median follow-up of 114 months (range 18-139 months), the 5-year overall survival (OS) and metastasis-free survival (MFS) rates in the concurrent chemoradiotherapy (CCRT) group were significantly higher than those observed in the RT-alone group (OS, 73.2% versus 60.2%, P = 0.028; MFS, 74.7% versus 63.0%, P = 0.027). However, CCRT did not improve locoregional failure-free survival significantly. Subgroup analyses showed that the superiorities of CCRT mainly existed in the T3-4N0-1 stage subgroup (OS: HR = 0.394, P = 0.034). The grade 3/4 late toxic effects were similar in the two groups.

CONCLUSION(S)

The long-term follow-up data confirms the role of CCRT as a treatment of locoregionally advanced NPC. Oxaliplatin can be considered as an alternative optional therapeutic regimen for these patients due to its high efficiency and low toxic effect.

Anti-tumor effect of oncolytic herpes simplex virus G47delta on human nasopharyngeal carcinoma

Oncolytic herpes simplex virus (HSV) can replicate in and kill cancer cells without harming normal tissue. G47Δ is a third-generation HSV vector. In this study, the therapeutic effects of G47Δ on human nasopharyngeal carcinoma (NPC) were determined in vitro and in vivo. The human NPC cell lines CNE-2 and SUNE-1, primary normal nasopharyngeal epithelial cells (NPECs), and immortalized nasopharyngeal cells NP-69 and NPEC2/Bmi1 were infected with G47Δ at different multiplicities of infection (MOIs). The survival of infected cells was observed daily. Two subcutaneous models of NPC were established with CNE-2 and SUNE-1 in Balb/c nude mice. G47Δ or virus buffer as control was injected into the subcutaneous tumors. Tumor size was measured twice a week, and animals were euthanized when the diameter of their tumors exceeded 18 mm or when the animals appeared moribund. For the NPC cell lines CNE-2 and SUNE-1, more than 85% and 95% of cells were killed on day 5 after G47Δ infection at MOI = 0.01 and MOI = 0.1, respectively. Similar results were observed for an immortalized cell line NPEC2/Bmi-1. A moderate effect of G47Δ was also found on another immortalized cell line NP-69, of which only 27.7% and 75.9% of cells were killed at MOI = 0.01 and MOI = 0.1, respectively. On the contrary, there was almost no effect observed on NPECs. The in vivo experiments showed that tumors in mice in the G47Δ-treated group regressed completely, and the mice exhibited much longer survival time than those in the control groups. Our results suggest that the potential therapeutic effects of G47Δ would be applicable for treatment of NPC patients in the future.

Different subsets of tumor infiltrating lymphocytes correlate with NPC progression in different ways

Background

Increasing amounts of evidence indicate that tumor infiltrating lymphocytes (TIL) are correlated with the prognosis of cancer patients. This study focuses on the association between the densities of tumor infiltrating cytotoxic T lymphocytes (CTL), activated CTL, regulatory T lymphocytes (Treg) and Th17 lymphocytes, and the prognosis and clinicopathological features of nasopharyngeal carcinoma (NPC) patients.

Results

Double immunohistochemical staining was performed in 106 biopsy specimens from newly diagnosed NPC patients. Prognostic values of infiltrating lymphocyte densities were evaluated by Kaplan-Meier analysis and Cox regression. The density of CD8+ TIL was positively correlated with lymph node metastasis, while the density of Foxp3⁺ TIL was negatively associated with T stage (P < 0.05). For survival evaluation, the density of Foxp3⁺ TIL or Foxp3⁺ TIL combined with GrB⁺ TIL together was associated with better overall survival (OS) and progression-free survival (PFS) (P < 0.01) in all patients and in the patients with late-stage diseases (Stages III and IV, P < 0.01). Meanwhile a low density of CD8⁺TIL or high ratio of FOXP3⁺TIL to CD8⁺TIL was correlated with better PFS in early stage patients (Stages I and II, P < 0.05). No significant association was found between IL-17⁺ TIL and clinicopathological characteristic or survival of NPC patients.

Conclusions

Our study identifies for the first time the tumor infiltrating Foxp3⁺ TIL as an independent favorable factor in the prognosis of NPC patients, especially for the patients with late-stage diseases.

Recombinant adeno-associated virus encoding Epstein-Barr virus latent membrane proteins fused with heat shock protein as a potential vaccine for nasopharyngeal carcinoma

Nasopharyngeal carcinoma (NPC) is a common cancer in Southern China and EBV is the most important pathogenesis. In this study, we explore the potential that a recombinant adeno-associated virus (rAAV) carrying a fusing gene containing heat shock protein as an adjuvant, EBV latent membrane proteins (LMP1 and LMP2) CTL epitope DNA as a vaccine prevents NPC. The tumor vaccine was devised by constructing a chimeric gene which contained EBV LMPs CTL epitope DNA fused with the heat shock protein gene as a tumor vaccine delivered via rAAV. Our results show that this vaccine can eliminate tumors in syngeneic animals and induce CTL activity in vitro. Taken together, the data suggest that this chimeric gene delivered by rAAV has potential as a NPC vaccine for prevention and therapy.

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.

Sclerosis of the Pterygoid Process in Untreated Patients with Nasopharyngeal Carcinoma

PURPOSE

To retrospectively evaluate the prevalence of pterygoid process sclerosis in patients with untreated nasopharyngeal carcinoma.

MATERIALS AND METHODS

This retrospective HIPAA-compliant study was performed after the institutional review board deemed it to be exempt from review and patient informed consent. Contrast material-enhanced computed tomographic (CT) scans of the neck obtained in 31 patients (22 men, nine women; mean age, 42 years; age range, 27-68 years) with untreated nasopharyngeal carcinoma and in 31 control subjects (17 men, 14 women; mean age, 43 years; age range, 19-62 years) were evaluated independently by two neuroradiologists. The presence of sclerosis of the pterygoid process-defined as increased attenuation in the medullary cavity and/or thickening of the cortical bone-was assessed. Other findings noted included pterygoid process erosion, enhancing tumor adjacent to the pterygoid process, and CT evidence of parapharyngeal extension of the tumor. The data were evaluated by using generalized estimating equations based on a binary logistic regression model.

RESULTS

The prevalence of pterygoid process sclerosis averaged for the two readers was 60% (37 of 62 subjects) among the patients with nasopharyngeal carcinoma but only 3% (two of 62 subjects) among the control subjects, indicating a highly significantly increased prevalence (P < .001) of this finding in the patients with nasopharyngeal carcinoma. The overall prevalences of pterygoid process erosion, parapharyngeal extension of tumor, and enhancing tumor adjacent to the pterygoid process were 27% (17 of 62 subjects), 47% (29 of 62 subjects), and 77% (48 of 62 subjects), respectively. Pterygoid process sclerosis was the sole skull base abnormality in 36% (11 of 31) of the patients with nasopharyngeal carcinoma.

CONCLUSION

Sclerosis of the pterygoid process, which was present in about half of the patients with untreated nasopharyngeal carcinoma, may reflect tumor proximity to or tumor invasion of the pterygoid process.

Nasopharyngeal carcinoma

Incidence of nasopharyngeal carcinoma has remained high in endemic regions. Diagnosing the disease in the early stages requires a high index of clinical acumen and, although most cross-sectional imaging investigations show the tumour with precision, confirmation is dependent on histology. Epstein-Barr virus (EBV)-encoded RNA signal is present in all nasopharyngeal carcinoma cells, and early diagnosis of the disease is possible through the detection of raised antibodies against EBV. The quantity of EBV DNA detected in blood indicates the stage and prognosis of the disease. Radiotherapy with concomitant chemotherapy has increased survival, and improved techniques (such as intensity-modulated radiotherapy), early detection of recurrence, and application of appropriate surgical salvage procedures have contributed to improved therapeutic results. Screening of high-risk individuals in endemic regions together with developments in gene therapy and immunotherapy might further improve outcome.

Optimal management of nasopharyngeal carcinoma

PURPOSE OF REVIEW

Given the high rate of mortality still associated with advanced stages of nasopharyngeal carcinoma, this review focuses on some specific aspects of this potentially curable disease that could translate into improved therapeutic approaches.

RECENT FINDINGS

Epstein-Barr viral-induced carcinogenesis is almost constantly reported in the undifferentiated type of nasopharyngeal carcinoma. Nasopharyngeal carcinoma retains clonal characteristics and p53 functionality up to late stages that may account for its high level of chemo- and radiotherapy sensitivity, with several cases of long-term survivors reported among patients with bone metastasis. Recent imaging and biologic techniques will help to identify patients at risk of distant failures (detection of plasma Epstein-Barr virus DNA) or those harboring posttherapeutic residual diseases (positron emission tomographic scan). Cisplatin-based induction chemotherapy has shown disease-free survival benefit, whereas concomitant chemoradiotherapy is associated with an improved local-regional control. Late radiation-induced toxicities (especially xerostomia) will hopefully be reduced using intensity-modulated radiation therapy. New therapeutic agents such as taxanes, or targeted therapies (epidermal growth factor receptor inhibitors) are of major interest in the challenge of circumventing resistance to alkylating agents.

SUMMARY

Better knowledge of nasopharyngeal carcinoma pathogenesis and biology, management of patients in highly specialized oncologic units, and careful selection of cytotoxic agents along with multimodality integrated therapeutic programs will likely yield to improved survival, particularly for patients with locally advanced nasopharyngeal carcinoma.