Advances and challenges in intensity-modulated radiotherapy for nasopharyngeal carcinoma

Study on the radiotherapy effect and serum neutral granulocyte lymphocyte ratio and inflammatory factor expression of nasopharyngeal carcinoma

Purpose

To compare target area delineation schemes in intensity-modulated radiotherapy (IMRT) effect on patients with locally advanced nasopharyngeal carcinoma (NPC).

Methods

A total of 88 NPC patients received IMRT and were assigned into control group (n = 44) and observation group (n = 44) based on MRI and CT imaging. In the control group, the treatment range was determined as the clinical target volume (CTV) as the gross tumor volume (GTV) + 5 mm. In the observation group, high-risk target areas CTVp1 was GTVp + 5 mm, lymphatic drainage area CTVn1 was GTVn + 5 mm, medium-risk CTVp2 was CTVp1 + 5 mm margin + the whole nasopharyngeal area, CTVn2 was CTVn1 + 5 mm. Radiotherapy treatment course was 6-8 weeks, four times a week.

Results

The observation group had higher total effective rate, with fewer complications. Neutrophil lymphocyte ratio (NLR), interleukin (IL)-6, and tumor necrosis factor (TNF)-α levels were lower after radiotherapy in both groups compared to before radiotherapy, with the observation group demonstrating lower levels than the control group. The effective group exhibited lower serum NLR, IL-6, and TNF-α compared to the non-effective group. T stage, target location, serum NLR, IL-6, and TNF-α were risk factors for the effect of radiotherapy.

Conclusions

Serum NLR, IL-6, and TNF-α have predictive significance for radiotherapy effect.

YAP nuclear translocation facilitates radiation resistance in nasopharyngeal carcinoma cells

OBJECTIVES

Investigate the role of the Hippo-YAP signaling pathway in radioresistant Nasopharyngeal Carcinoma (NPC).

METHODS

Establishment of radioresistant CNE-1 cells (CNE-1-RR) by gradually increasing ionizing radiation (IR) doses, and identifying the apoptosis of CNE-1-RR by flow cytometry. We employed immunoblot and immunofluorescence staining to detect the expression of YAP in both CNE-1-RR and control group cells. Moreover, we validated the role of YAP in CNE-1-RR by inhibiting its nuclear translocation.

RESULTS

In contrast to the control group, radioresistant NPC cells demonstrated significant YAP dephosphorylation and nuclear translocation. CNE-1-RR cells exhibited enhanced activation of γ-H2AX (Ser139) upon exposure to IR and greater recruitment of double-strand breaks (DSBs) repair-related proteins. Additionally, inhibiting YAP nuclear translocation in radioresistant CNE-1-RR cells significantly increased their sensitivity to radiotherapy.

CONCLUSIONS

The present investigation has unveiled the intricate mechanisms and physiological roles of YAP in CNE-1-RR cells exhibiting resistance to IR. Based on our findings, it can be inferred that a combinational therapeutic strategy involving radiotherapy and inhibitors that impede the nuclear translocation of YAP holds promising potential for treating radioresistant NPC.

Automatic detection and recognition of nasopharynx gross tumour volume (GTVnx) by deep learning for nasopharyngeal cancer radiotherapy through magnetic resonance imaging

BACKGROUND

In this study, we propose the deep learning model-based framework to automatically delineate nasopharynx gross tumor volume (GTVnx) in MRI images.

METHODS

MRI images from 200 patients were collected for training-validation and testing set. Three popular deep learning models (FCN, U-Net, Deeplabv3) are proposed to automatically delineate GTVnx. FCN was the first and simplest fully convolutional model. U-Net was proposed specifically for medical image segmentation. In Deeplabv3, the proposed Atrous Spatial Pyramid Pooling (ASPP) block, and fully connected Conditional Random Field(CRF) may improve the detection of the small scattered distributed tumor parts due to its different scale of spatial pyramid layers. The three models are compared under same fair criteria, except the learning rate set for the U-Net. Two widely applied evaluation standards, mIoU and mPA, are employed for the detection result evaluation.

RESULTS

The extensive experiments show that the results of FCN and Deeplabv3 are promising as the benchmark of automatic nasopharyngeal cancer detection. Deeplabv3 performs best with the detection of mIoU 0.8529 ± 0.0017 and mPA 0.9103 ± 0.0039. FCN performs slightly worse in term of detection accuracy. However, both consume similar GPU memory and training time. U-Net performs obviously worst in both detection accuracy and memory consumption. Thus U-Net is not suggested for automatic GTVnx delineation.

CONCLUSIONS

The proposed framework for automatic target delineation of GTVnx in nasopharynx bring us the desirable and promising results, which could not only be labor-saving, but also make the contour evaluation more objective. This preliminary results provide us with clear directions for further study.

Effects of Baduanjin exercise in nasopharyngeal carcinoma patients after chemoradiotherapy: a randomized controlled trial

OBJECTIVE

To evaluate the effects of traditional Chinese Baduanjin Qigong exercises on the physical and psychological recovery of patients with nasopharyngeal carcinoma after chemoradiotherapy.

METHODS

Eighty-eight nasopharyngeal carcinoma patients who had completed chemoradiotherapy were randomly divided into the Baduanjin intervention group (n = 44) and the control group (n = 44). Patients in the intervention group practised Baduanjin exercise for 12 weeks, with the frequency of 40 min a day and 5 days a week after discharge from the hospital. Participants in the control group received usual care. Outcome indicators included quality of life (QOL), complications, cancer-related fatigue (CRF), sleep quality, anxiety, and depression. The intention-to-treat and per-protocol populations were compared using univariate analysis of variance. Partial eta squared was used as a measure of the effect size.

RESULTS

A total of 75 patients completed the study. In the intention-to-treat analysis, after 12 weeks of exercise intervention, there were significant increases in the global FACT-H&N (95% CI = 2.09 to 11.47, η_p² = 0.088), social/family well-being (95% CI = 0.13 to 2.26, η_p² = 0.055), emotional well-being (95% CI = 0.34 to 2.44, η_p² = 0.074), and head and neck cancer subscale scores (95% CI = 0.17 to 3.86, η_p² = 0.052) in the Baduanjin group compared with the control group at the 12th week. In the per-protocol analysis, there were significant increases in the global FACT-H&N (95% CI = 4.11 to 11.75, η_p² = 0.190), physical well-being (95% CI: 0.50 to 3.04, η_p² = 0.096), social/family well-being (95% CI: 0.32 to 2.15, η_p² = 0.090), emotional well-being (95% CI: 0.60 to 2.53, η_p² = 0.125), functional well-being (95% CI: 0.25 to 2.49, η_p² = 0.075), and head and neck cancer subscale (95% CI: 1.08 to 4.08, η_p² = 0.139) scores in the Baduanjin group compared with the control group at the 12th week.

CONCLUSION

The findings in this study indicate that Baduanjin exercise is an effective and appropriate intervention for improving quality of life and is worthy of recommendation and implementation by oncology nurses in the rehabilitation process of patients with nasopharyngeal carcinoma.

Recurrence risk stratification based on Epstein–Barr virus DNA to identify enlarged retropharyngeal lymph nodes of nasopharyngeal carcinoma: A model-histopathologic correlation study

Background

Accurate assessment of the nature of enlarged retropharyngeal lymph nodes (RLN) of nasopharyngeal carcinoma (NPC) patients after radiotherapy is related to selecting appropriate treatments and avoiding unnecessary therapy. This study aimed to develop a non-invasive and effective model for predicting the recurrence of RLN (RRLN) in NPC.

Materials and methods

The data of post-radiotherapy NPC patients (N = 76) with abnormal enlargement of RLN who underwent endonasopharyngeal ultrasound-guided fine-needle aspirations (EPUS-FNA) were examined. They were randomly divided into a discovery (n = 53) and validation (n = 23) cohort. Univariate logistic regression was used to assess the association between variables (magnetic resonance imaging characteristics, EBV DNA) and RRLN. Multiple logistic regression was used to construct a prediction model. The accuracy of the model was assessed by discrimination and calibration, and decision curves were used to assess the clinical reliability of the model for the identification of high risk RLNs for possible recurrence.

Results

Abnormal enhancement, minimum axis diameter (MAD) and EBV-DNA were identified as independent risk factors for RRLN and could stratify NPC patients into three risk groups. The probability of RRLN in the low-, medium-, and high-risk groups were 37.5, 82.4, and 100%, respectively. The AUC of the final predictive model was 0.882 (95% CI: 0.782–0.982) in the discovery cohort and 0.926 (95% CI, 0.827–1.000) in the validation cohort, demonstrating good clinical accuracy for predicting the RRLN of NPC patients. The favorable performance of the model was confirmed by the calibration plot and decision curve analysis.

Conclusion

The nomogram model constructed in the study could be reliable in predicting the risk of RRLN after radiotherapy for NPC patients.

Accuracy Evaluation of Collapsed Cone Convolution Superposition Algorithms for the Nasopharynx Interface in the Early Stage of Nasopharyngeal Carcinoma

This study combined the use of radiation dosimeteric measurements and a custom-made anthropomorphic phantom in order to evaluate the accuracy of therapeutic dose calculations at the nasopharyngeal air-tissue interface. The doses at the nasopharyngeal air-tissue interface obtained utilizing the Pinnacle and TomoTherapy TPS, which are based on collapsed cone convolution superposition (CCCS) algorithms, were evaluated and measured under single $10\times 10\text{c}{\text{m}}^2$ , $2\times 2\text{c}{\text{m}}^2$ , two parallel opposed $2\times 2\text{c}{\text{m}}^2$ and clinical fields for early stage of nasopharyngeal carcinoma by using EBT3, GR-200F, and TLD 100. At the air-tissue interface under a $10\times 10\text{c}{\text{m}}^2$ field, the TPS dose calculation values were in good agreement with the dosimeter measurement with all differences within 3.5%. When measured the single field $2\times 2\text{c}{\text{m}}^2$ , the differences between the average dose were measured at the distal interface for EBT3, GR-200F, and TLD-100 and the calculation values were -15.8%, -16.4%, and -4.9%, respectively. When using the clinical techniques such as IMRT, VMAT, and tomotherapy, the measurement results at the interface for all three techniques did not imply under dose. Small-field sizes will lead to dose overestimation at the nasopharyngeal air-tissue interface due to electronic disequilibrium when using CCCS algorithms. However, under clinical applications of multiangle irradiation, the dose errors caused by this effect were not significant.

Induction chemotherapy followed by intensity-modulated radiotherapy versus concurrent chemoradiotherapy in nasopharyngeal carcinoma: A retrospective analysis

OBJECTIVES

The optimal treatment strategy of combining systemic chemotherapy and radiotherapy for nasopharyngeal carcinoma (NPC) is controversial. This study aimed to compare the efficacy and toxicities of induction chemotherapy followed by intensity-modulated radiotherapy (IC-RT) versus concurrent chemoradiotherapy (CCRT) in NPC.

METHODS

Of 448 stage II-IVb NPC patients treated with IC-RT or CCRT were retrospectively analysed. The primary outcome was overall survival, which was analysed by using Kaplan-Meier curves and log-rank (Mantel-Cox) test.

RESULTS

The median follow-up was 66 months (interquartile range, 46-84 months). There was no statistically significant difference in the estimated 5-year overall survival (OS), progression-free survival (PFS), distance metastasis-free survival (DMFS) and locoregional relapse-free survival (LRFS) between IC-RT group and CCRT group (OS: 89.5% vs 91.7%, P = .568; PFS: 85.2% vs 87.5%, P = .615; DMFS: 90.9% vs 91.7%, P = .847; LRFS: 92.0% vs 96.9%, P = .104). In the multivariate analysis, the treatment group (IC-RT vs CCRT) was not an independent prognostic factor for OS, PFS, DMFS and LRFS. Less advanced tumour stage and lymph node stage were predictive of higher OS. EBV-DNA level was an independent prognostic factor that was only significantly associated with LRFS.

CONCLUSIONS

IC-RT achieves similar survival outcomes and treatment-related toxicities as CCRT in OS, PFS, DMFS and LRFS for patients with NPC. We need multicentre randomised controlled trials to reconfirm our data.

Comparing endoscopic surgeries with open surgeries in terms of effectiveness and safety in salvaging residual or recurrent nasopharyngeal cancer: Systematic review and meta-analysis

Consensus has yet to be reached on the optimal operation for patients with residual or recurrent nasopharyngeal carcinoma (NPC). To compare effectiveness and safety of open surgery and endoscopic surgery for patients with residual or recurrent NPC. Pubmed, Embase, and Cochrane were searched for relevant publications from January 1, 2000 to May 1, 2017. Included studies reported specific residual or local recurrent nasopharyngeal cancer survival data. Proportional meta-analysis was performed on both outcomes with a random-effects model, and the 95% confidential intervals were calculated by Stata 12.0 software. For patients with different tumor classification, a downward trend of 2-year overall survival (OS) was observed for both surgical populations. Endoscopic surgeries achieved bigger rates than open surgeries in patients with recurrent tumor (rT) 1, rT2, and rT3 (93% vs 87%, 77% vs 63%, 67% vs 53%). As for patients with rT4, 2-year OS was similar (35% vs 35%).In addition, the former is less severe complications, lower local recurrence rates (27% vs 32%). Our study found that, compared to open surgery, endoscopic surgery was a safer and more effective treatment modality in managing patients with recurrent or residual NPC.

Rac1: A potential radiosensitization target of human nasopharyngeal carcinoma CNE2 cells

Radiotherapy has a high cure rate for early nasopharyngeal carcinoma(NPC). However, the radiation resistance of poorly differentiated NPC cells impacts the effectiveness of treatment of early-stage NPC patients. Here, we explored the relationship between Ras-related C3 botulinum toxin substrate 1(Rac1) expression and NPC radiosensitivity. In vitro and in vivo studies revealed that upregulation of Rac1, when combined with X-ray treatment, increased growth inhibition and induced remarkable morphological changes and apoptosis in CNE2 cells. Furthermore, rupturing of the cell and nuclear membranes, degeneration of the cristae and significant swelling of the mitochondria were observed, which were consistent with the high apoptotic rate. The Rac1(+) cells exhibited approximately 50% more migration compared with that of the NC and Rac1(-) cells. The overexpression of Rac1 can increase the radiation sensitivity of NPC CNE2 cells, and the mechanism may be closely related to the oxidative damage of mitochondria. Rac1 might be a potential target for radiosensitization in poorly differentiated NPC.

Circulating miR-214-3p predicts nasopharyngeal carcinoma recurrence or metastasis

BACKGROUND

Due to the remarkably stable form in the bloodstream, circulating microRNAs (miRNAs) are indicated as promising novel minimally invasive biomarkers in many cancers. However, available data of miRNAs in nasopharyngeal carcinoma (NPC) are relatively limited.

METHODS

Based on the GEO database and previous published reports, 21 dysregulated miRNAs were selected for screening via microarray analysis (20 NPC samples vs 10 controls). Dysregulated miRNAs were then detected and verified by the method of quantitative reverse transcription-polymerase chain reaction (qRT-PCR) in the training and validation sets. The candidate miR-214-3p was then evaluated in the evaluation set, including the association between miR-214-3p and clinicopathological characteristics, dynamic changes in NPC patients and the predictive value for NPC recurrence or metastasis.

RESULTS

Seven miRNAs were significantly altered in comparison with healthy controls by microarray analysis. MiR-214-3p was the most significantly expressed in training and validation sets by qRT-PCR. Plasma miR-214-3p expressions were significantly associated with UICC stages and NPC recurrence or metastasis. Plasma miR-214-3p expressions showed a gradual decrease during the follow-up after treatment in NPC patients. Patients with recurrence or metastasis were always accompanied with higher levels of plasma miR-214-3p at the same time point. High pretreatment miR-214-3p expression (≥3.12) was significantly associated with NPC recurrence or metastasis by log-rank test using Kaplan-Meier survival curve analysis (P = 0.006).

CONCLUSIONS

Circulating miR-214-3p can serve as a noninvasive biomarker for the prediction of recurrence or metastasis in NPC patients.

PNCK depletion inhibits proliferation and induces apoptosis of human nasopharyngeal carcinoma cells in vitro and in vivo

Purpose: Recent studies indicate that pregnancy upregulated non-ubiquitous calmodulin kinase (PNCK) is significantly up-regulated in breast and renal carcinomas. However, the expression profile and its biological relevance of PNCK in nasopharyngeal carcinoma (NPC) have not been elucidated.

Methods: The expression level of PNCK was detected in specimens of NPC (n=10) and normal tissues (n=10) by real-time PCR and immunohistochemistry. Celigo Cell Counting and MTT assay were used to measure cell viability. Apoptosis was detected by flow cytometric analysis and caspases 3/7 activity assay. Real-time PCR and Western blotting were performed to evaluate the expression of PNCK. The bioluminescence imaging was used to evaluate the effects of PNCK knockdown on tumor growth using a xenograft animal model. The global gene expression profile was determined in wild type and PNCK-depleted CNE-2 cells via transcriptomics analysis. For mechanical investigation, the changes of PI3K/AKT/mTOR signaling pathway were detected by Western blotting.

Results: The mRNA and protein levels of PNCK were increased in human NPC samples. In vitro experiments showed that shRNA or CRISPR-Cas9 mediated silencing of PNCK inhibited proliferation and induced apoptosis in NPC cells. In addition, in vivo assay revealed that knockdown of PNCK suppressed tumor growth. Consistently, a significant reduction of tumor bioluminescence in mice inoculated with PNCK-knockdown cells compared to that of control cells. In gene expression, the transcriptomics analysis revealed that there were 589 upregulated genes and 589 downregulated genes in PNCK-knockdown cells. Ingenuity Pathway Analysis (IPA) identified significant changes of PI3K/AKT/mTOR signaling pathway in PNCK-knockdown cells. Furthermore, western blot analysis revealed that interference with PNCK reduced the phosphorylation levels of PI3K, AKT and mTOR in CNE-2 cells.

Conclusion: This study for the first time demonstrates that knockdown of PNCK could suppress growth and induce apoptosis of NPC cells both in vitro and in vivo by regulating PI3K/AKT/mTOR signaling pathway. These findings suggest that PNCK might be a novel therapeutic target for NPC treatment.

Downregulation of CD166 inhibits invasion, migration, and EMT in the radio-resistant human nasopharyngeal carcinoma cell line CNE-2R

Objective: CD166 is known as a tumor stem cell specific marker, associating with tumor metastasis. The purpose of this study was to further discuss CD166 gene on cell proliferation, invasion, metastasis, and the epithelial-mesenchymal transition (EMT) in CNE-2R cell line of nasopharyngeal carcinoma (NPC). Materials and methods: CNE-2R cells were transfected with lentivirus CD166-shRNA, and quantitative reverse transcription polymerase chain reaction (RT-qPCR), and Western blotting were used to confirm the silencing effects. The wound healing test and transwell test were carried out to assess cell invasive and migratory abilities in vitro. With the establishment of xenograft nude mouse model, Western blotting and immunohistochemistry were undertaken to detect the expression level of E-cadherin, N-cadherin, and vimentin. In vivo metastasis detection was carried out by injecting tumor cells into nude mice via the tail vein. Results: The invasive and migratory abilities of CNE-2R cells were significantly reduced after CD166 was downregulated. In addition, silencing of CD166 of CNE-2R cells increased the expression of E-cadherin, while down-regulated the expression of N-cadherin and vimentin. Immunohistochemistry of tumors showed consistent results with in-situ tumor formation experiment. Additionally, the growth of transplanted tumor was inhibited. In addition, in vivo metastasis test proved that knockdown of CD166 suppressed pulmonary metastasis and liver metastasis according to hematoxylin and eosin (H&E) staining. Expression of E-cadherin increased, while expression of N-cadherin and vimentin decreased, as revealed by Western blotting of metastatic lung tumors. Conclusion: Silencing of CD166 in CNE-2R cells evidently inhibited proliferation, invasion, metastasis, and EMT process in vivo and in vitro.

Concurrent Chemoradiotherapy for Loco-regionally Advanced Nasopharyngeal Carcinoma: Treatment Outcomes and Prognostic Factors

Background:

We conducted this study to contribute to resolving some controversial issues on management of nasopharyngeal carcinoma.

Methods:

Thirty-two patients with stage III-IVB nasopharyngeal carcinoma were included in this retrospective study. All patients received concurrent chemoradiotherapy with either 3D conformal radiotherapy or intensity-modulated radiotherapy. We retrospectively analyzed the survival outcome, prognostic factors for survival, and toxicity outcome.

Results:

The 2- and 5-year overall survival rates were 89.9% and 82.6%. The 2- and 5-year distant metastasis-free survival rates were 83.2% and 79.4%. The 2- and 5-year loco-regional recurrence-free survival rates were 83.3% and 79.5%. Addition of induction chemotherapy to concurrent chemoradiotherapy did not improve survival outcomes. The survival benefit of intensity-modulated radiotherapy over 3D conformal radiotherapy was not clear. Intensity-modulated radiotherapy significantly decreased the development of late toxicities compared with 3D conformal radiotherapy. Total RT dose was prognostic factor for overall, loco-regional recurrence-free, and distant metastasis-free survival. Temporary RT interruption was prognostic factor for overall survival. Daily RT dose was prognostic factor for distant metastasis-free survival.

Conclusions:

Concurrent chemoradiotherapy resulted in high survival rates with an acceptable level of toxicities in patients with loco-regionally advanced nasopharyngeal carcinoma. To confirm the results of this study, well-designed randomized prospective trials are warranted.

TRIM24 siRNA induced cell apoptosis and reduced cell viability in human nasopharyngeal carcinoma cells

Nasopharyngeal carcinoma (NPC) is a common cancer occurring primarily in East Asia and Africa. The high rate of recurrence and metastasis of NPC continuously endangers the health of patients. The present study aimed to identify the underlying mechanisms involved in the progression of NPC and provide experimental basis to develop a novel and efficient agent against NPC. The present study measured the expression level of tripartite motif containing 24 (TRIM24) in tumor tissues from NPC patients using reverse transcription quantitative polymerase chain reaction. Subsequently, Cell Counting kit‑8 and flow cytometry were used to detect the cell proliferation and apoptosis of NPC cell lines HONE1 and CNE1 cells where the TRIM24 gene was knocked‑down with small interfering RNA (siRNA). Further, caspase kits and western blot analysis were used to detect the expression of apoptosis and angiogenesis‑associated proteins. The present study detected a higher expression level of TRIM24 in tumor tissues and NPC cell lines and lower cell viability and higher apoptotic rate were observed when TRIM24 was silenced. Meanwhile, upregulated caspase‑3 and caspase‑9 indicated induced cell apoptosis in HONE1 and CNE1 cells following the treatment with TRIM24 siRNA. Additionally, the downregulated expression level of vascular endothelial growth factor (VEGF) and VEGF receptor 2 suggested inhibited angiogenesis of NPC cells. Additionally, the reduced levels of janus kinase 2 (JAK2) and signal transducer and activator of transcription 3 (STAT3) indicated a blocked JAK2/STAT3 signaling pathway. However, there was no direct evidence that inactivation of the JAK2/STAT3 signaling pathway was involved in regulation of siTRIM24, these results suggested that TRIM24 has an important role in the growth of NPC. Additionally, silenced TRIM24 may lead to inhibited cell proliferation and induced cell apoptosis in NPC cells. The limitation of this study was that HONE1, CNE1 and CNE2 cells may have been contaminated with other cells. Further experiments with validated NPC cells may be needed.

Dynamic Changes in Plasma MicroRNAs Have Potential Predictive Values in Monitoring Recurrence and Metastasis of Nasopharyngeal Carcinoma

Although circulating microRNAs (miRNAs) have already proven to be useful as diagnostic and prognostic biomarkers in nasopharyngeal carcinoma (NPC), the potential of these molecules to monitor patients over time has been less explored. This study aimed to analyze dynamic changes in plasma miRNAs before and after treatment and explore their clinical significance in monitoring recurrence and metastasis of NPC. Candidate miRNAs were screened by microarray analysis and validated by real-time quantitative polymerase chain reaction (RT-qPCR). In the follow-up cohort including 102 patients, blood samples (plasma) were collected before the treatment initiation, 3 months, 6 months, and 12 months after treatments, and at the time of any recurrence or metastasis. Among these plasma miRNAs, miR-9-3p, miR-124-3p, miR-892b, and miR-3676-3p were significantly upregulated (P = 0.018, P = 0.039, P = 0.001, and P = 0.01, resp.) after treatment compared with pretreatment, and the four plasma miRNAs were downregulated again at recurrence or metastasis (P < 0.001, P = 0.015, P = 0.003, and P = 0.026, resp.). The dynamic changes in plasma miRNAs after treatment reflect the outcome of the disease and have the potential to monitor recurrence and metastasis in patients with NPC.

Application of intensity-modulated radiation therapy in the treatment of nasopharyngeal carcinoma

The objective of the present study was to investigate the application values of the intensity-modulated radiation therapy (IMRT) and the three-dimensional conformal radiation therapy (3D-CRT) in the treatment of nasopharyngeal carcinoma (NPC). A total of 124 patients diagnosed with nasopharyngeal carcinomas were included into the study and randomly divided into the control group and the observation group, with 62 patients in each group. The 3D-CRT combined with postoperative chemotherapy were performed on the control group and the observation group received IMRT combined with postoperative chemotherapy, and then were followed up for a median duration of 25.5 months. Comparison of the survival analysis of the two groups showed no differences between them in terms of the total effective rate and effectiveness (P>0.05), or radiotherapy complications (P>0.05). In addition, no significant differences between the two groups were found in the follow-up local tumor control probability (TCP), regional lymph node control rate, distant metastasis-free rate, tumor-free survival rate, recurrence rate and overall survival rate (P>0.05). Furthermore, there was no difference between the two groups in the overall score of quality of life (P>0.05). The present study concludes that the IMRT and the 3D-CRT have almost the same short-term and long-term clinical effects in the treatment of nasopharyngeal carcinoma and both of them have high effectiveness and safety.

Validation of the 8th edition of the UICC/AJCC staging system for nasopharyngeal carcinoma treated with intensity-modulated radiotherapy

An accurate TNM staging system is crucial for treatment guidance and prognosis prediction in nasopharyngeal carcinoma (NPC) patients. In this retrospective study, we evaluated the 8th edition of the Union for International Cancer Control/American Joint Committee on Cancer (UICC/AJCC) staging system for NPC treated with intensity-modulated radiotherapy (IMRT). A total of 608 patients with biopsy-proven, non-metastatic NPC, treated with IMRT between January 2008 and March 2010, were enrolled. The 5-year overall survival (OS), disease-free survival (DFS), local relapse-free survival (LRFS), and distant metastasis-free survival (DMFS) rates were 81.5%, 80.1%, 86.0%, and 81.1%, respectively. The LRFS rates of patients with stages T1 vs. T2, T2 vs. T3, and T1 vs. T3 did not differ between the 7th and 8th editions. By contrast, the DMFS rates of patients with N0 vs. N1, N1 vs. N2, and N2 vs. N3 differed between the 8th and the 7th editions, though no difference was observed between N3a and N3b, according to the 7th edition. The difference in OS between stages II and III, and between stages III and IVa, was larger according to the 8th edition than the 7th edition. There was no difference in the OS between stages I and II. These data indicate that in the IMRT era, the 8th edition staging system can predict the prognosis of NPC patients more accurately than the 7th edition.

Analysis on clinical characteristics and influencing factors of patients with locoregionally advanced nasopharyngeal carcinoma

BACKGROUND

To explore the independent prognostic factors for the recurrence/metastasis of patients with locoregionally advanced nasopharyngeal carcinoma (LANPC).

MATERIALS AND METHODS

A total of 604 patients initially diagnosed as LANPC by pathohistology in Fujian Provincial Cancer Hospital were selected to analyze the relationship between the clinical pathological patterns, therapeutic protocols and clinical stages with the recurrence/metastasis of LANPC.

RESULTS

The 1-, 3- and 5-year locoregionally recurrent rates of LANPC patients were 2.0%, 9.5% and 12.9% respectively, with average recurrent period being 78 months. Univariate analysis results indicated that clinical stages had certain influence on the recurrent period of LANPC patients. However, COX regression models showed that ages, genders and clinical stages were not the independent prognostic factors influencing the recurrence. The 1-, 3- and 5-year metastatic rates of LANPC patients were 6.6%, 17.5% and 18.8% respectively, with average metastatic period of 73 months. Univariate analysis results demonstrated that ages, N stages, clinical stages, locations of lymph node, retropharyngeal lymph node and extracapsular invasion of lymph node had certain influence on the metastatic period of LANPC patients. Additionally, further COX regression analysis results suggested that T stages, reduction protocols and extracapsular invasion of lymph node were the independent prognostic factors influencing the metastasis of patients with LANPC, in which T stages and extracapsular invasion of lymph node were the pestilent factors while reduction protocols the protective factor.

CONCLUSIONS

Induction chemotherapy is beneficial to LANPC patients with initial treatment, and the metastatic rate decreases greatly after the application of reduction chemotherapy.