Significant prognosticators after primary radiotherapy in 903 nondisseminated nasopharyngeal carcinoma evaluated by computer tomography

Patterns of failure in patients with nasopharyngeal cancer of Northeastern region of India: a retrospective observational study

PURPOSE

We aimed to analyze patterns of failure and disease volume-treatment outcomes in patients with Nasopharyngeal carcinoma (NPC) treated with definitive radiation with or without concurrent chemotherapy at a tertiary cancer centre in northeast India.

METHODS

From February 2018 to February 2022, 99 histopathologically proved non-metastatic NPC patients treated with curative-intent RT with or without chemotherapy were retrospectively analyzed. Locally advanced patients received neoadjuvant or adjuvant chemotherapy. The Cox proportional hazards model was used to investigate the impact of various prognostic factors on locoregional free survival (LRFS), distant metastasis free survival (DMFS), progression free survival (PFS) and overall survival (OS). The log-rank test and Kaplan-Meir curves compared outcome variables based on ROC analysis-classified tumor volume.

RESULTS

During a median follow up of 25.4 months (17.3-39.2), 35(35.4%) patients developed recurrence. Twenty-three patients developed locoregional failures, of which 11 were in-field; 12 patient showed an out-field failure. The 3-year LRFS, DMFS, PFS and OS was 71.10%, 70.90%, 64.10% and 74.10% respectively. There was statistically significant difference in LRFS according to T staging (p < 0.0001). Gross tumor volume (GTVp) and gross nodal volume (GTVn) were an independent prognostic factor for OS, PFS, LRFS and DMFS. The cut-off volumes for GTVp and GTVn for distant metastases and locoregional failure, respectively, were found to be 13 and 22.7 mL and 3.7 and 39.2 mL, respectively, by ROC curve analysis. Based on this, 99 patients were divided into three subgroups. OS demonstrated significant differences among patients in different volume subgroups for GTVp (p = 0.03) and GTVn (p = 0.00024).

CONCLUSIONS

For NPC patients who undergo curative IMRT, primary tumour and nodal volumes are independent prognostic indicators. GTVp and GTVn are highly predictive of local control, distant metastases, disease-free survival, and overall survival. This justifies their use as quantitative prognostic indicator for NPC.

A contrast-enhanced CT radiomics-based model to identify candidates for deintensified chemoradiotherapy in locoregionally advanced nasopharyngeal carcinoma patients

OBJECTIVES

To develop a contrast-enhanced CT (CECT) radiomics-based model to identify locoregionally advanced nasopharyngeal carcinoma (LA-NPC) patients who would benefit from deintensified chemoradiotherapy.

METHODS

LA-NPC patients who received low-dose concurrent cisplatin therapy (cumulative: 150 mg/m2), were randomly divided into training and validation groups. 107 radiomics features based on the primary nasopharyngeal tumor were extracted from each pre-treatment CECT scan. Through Cox regression analysis, a radiomics model and patients' corresponding radiomics scores were created with predictive independent radiomics features. T stage (T) and radiomics score (R) were compared as predictive factors. Combining the N stage (N), a clinical model (T + N), and a substitution model (R + N) were constructed.

RESULTS

Training and validation groups consisted of 66 and 33 patients, respectively. Three significant independent radiomics features (flatness, mean, and gray level non-uniformity in gray level dependence matrix (GLDM-GLN)) were found. The radiomics score showed better predictive ability than the T stage (concordance index (C-index): 0.67 vs. 0.61, AUC: 0.75 vs. 0.60). The R + N model had better predictive performance and more effective risk stratification than the T + N model (C-index: 0.77 vs. 0.68, AUC: 0.80 vs. 0.70). The R + N model identified a low-risk group as deintensified chemoradiotherapy candidates in which no patient developed progression within 3 years, with 5-year progression-free survival (PFS) and overall survival (OS) both 90.7% (hazard ratio (HR) = 4.132, p = 0.018).

CONCLUSION

Our radiomics-based model combining radiomics score and N stage can identify specific LA-NPC candidates for whom de-escalation therapy can be performed without compromising therapeutic efficacy.

CLINICAL RELEVANCE STATEMENT

Our study shows that the radiomics-based model (R + N) can accurately stratify patients into different risk groups, with satisfactory prognosis in the low-risk group when treated with low-dose concurrent chemotherapy, providing new options for individualized de-escalation strategies.

KEY POINTS

• A radiomics score, consisting of 3 predictive radiomics features (flatness, mean, and GLDM-GLN) integrated with the N stage, can identify specific LA-NPC populations for deintensified treatment. • In the selection of LA-NPC candidates for de-intensified treatment, radiomics score extracted from primary nasopharyngeal tumors based on CECT can be superior to traditional T stage classification as a predictor.

Dual-energy CT for the detection of skull base invasion in nasopharyngeal carcinoma: comparison of simulated single-energy CT and MRI

BACKGROUND

Skull base invasion in nasopharyngeal carcinoma (NPC) was shown to be a poor negative prognostic factor, and dual-energy CT (DECT) has heralded a new approach to detect this condition. The study aims to evaluate the value of DECT for detection of skull base invasion in NPC and compare the diagnostic performance of DECT with those of simulated single-energy CT (SECT) and MRI.

METHODS

The imaging findings of 50 NPC patients and 31 participants in control group which underwent DECT examinations were assessed in this retrospective study. The skull base invasions were evaluated using 5-point scale by two blind observers. ROC analysis, Mcnemar test, paired t test, weighted K statistics and intraclass correlation coefficient were performed to evaluate the diagnostic performance of simulated SECT, MRI and DECT.

RESULTS

Quantitative analysis of DECT parameters showed higher normalized iodine concentration and effective atomic number values in sclerosis and lower values in erosion than those in normal bones (both p < 0.05). Compared with simulated SECT and MRI, the diagnostic sensitivity for DECT was significantly improved from 75% (simulated SECT) and 84.26% (MRI) to 90.74% (DECT) (both p < 0.001), specificity from 93.23% and 93.75% to 95.31 (both p < 0.001), accuracy from 86.67% and 90.33% to 93.67%, and AUC from 0.927 and 0.955 to 0.972 (both p < 0.05), respectively.

CONCLUSIONS

DECT demonstrates better diagnostic performance than simulated SECT and MRI for detecting skull base invasions in NPC, even those slight bone invasions in early stage, with higher sensitivity, specificity and accuracy.

Failure Patterns of Recurrence and Metastasis After Intensity-Modulated Radiotherapy in Patients With Nasopharyngeal Carcinoma: Results of a Multicentric Clinical Study

Purpose

This study aimed to explore factors associated with recurrence and metastasis after intensity-modulated radiotherapy (IMRT) in patients with nasopharyngeal carcinoma (NPC) and provide evidence for NPC treatment.

Methods

We retrospectively analysed the treatment dose and survival outcomes of 645 patients with nasopharyngeal carcinoma without distant metastases treated with IMRT for the first time at three treatment centres in the Guangxi Zhuang Autonomous Region, China, between January 2009 and December 2012.

Results

There were 9.3% of patients (60/645) had recurrence and 17.5% (113/645) had distant metastasis 5 years after treatment. The 1-year, 3-year and 5-year local recurrence rates were 0.9%, 6.5% and 9.0% respectively. And the 1-year, 3-year and 5-year distant metastasis rates were 3.4%, 10% and 17.2%, respectively. In the 60 patients with recurrence, the in-field, marginal-field, and out-field recurrence rates were 93.3% (56/60), 5.0% (3/60) and 1.7% (1/60), respectively. Recurrence failures occurring within the first three years after treatment accounted for 81.7% (49/60). In the 113 patients with metastasis, the size of the cervical lymph node, the presence of lower cervical lymph node metastasis, the residual cervical lymph node size and the time of residual cervical lymph node complete response (CR) were independent prognostic factors for DMFS (P <0.05).

Conclusion

Most recurrences occured in the first three years after IMRT. In-field recurrence was the most common pattern for loco-regional failure of NPC treatment. The risk of distant metastasis was positively correlated with higher N stage, lower neck nodal metastasis, larger size of cervical lymph nodes, and longer time to response for residual NPC in cervical adenopathy.

Value of skull base invasion subclassification in nasopharyngeal carcinoma: implication for prognostic stratification and use of induction chemotherapy

OBJECTIVES

Prognoses for nasopharyngeal carcinoma (NPC) between categories T2 and T3 in the Eighth American Joint Committee on Cancer (AJCC) staging system were overlapped. We explored the value of skull base invasion (SBI) subclassification in prognostic stratification and use of induction chemotherapy (IC) to optimize T2/T3 categorization for NPC patients.

METHODS

We retrospectively reviewed 1752 NPC patients from two hospitals. Eight skull base bone structures were evaluated. Survival differences were compared between slight SBI (T3 patients with pterygoid process and/or base of the sphenoid bone invasion only) and severe SBI (T3 patients with other SBIs) with or without IC using random matched-pair analysis. We calculated the prognosis and Harrel concordance index (C-index) for the revised T category and compared IC outcomes for the revised tumor stages.

RESULTS

Compared to severe SBI, slight SBI showed better 5-year overall survival (OS) (81.5% vs. 92.3%, p = 0.001) and progression-free survival (PFS) (71.5% vs. 83.0%, p = 0.002). Additional IC therapy did not significantly improve OS and PFS in slight SBI. The proposed T category separated OS, PFS, and locoregional recurrence-free survival in T2 and T3 categories with statistical significance. An improved C-index for OS prediction was observed in the proposed T category with combined confounding factors, compared to the AJCC T staging system (0.725 vs. 0.713, p = 0.046). The survival benefits of IC were more obvious in the advanced stage.

CONCLUSIONS

NPC patients with slight SBI were recommended to downstage to T2 category. The adjustment for T category enabled better prognostic stratification and guidance for IC use.

KEY POINTS

• For nasopharyngeal carcinoma (NPC) patients in T3 category, slight skull base invasion was a significant positive predictor for OS and PFS. • NPC patients with slight SBI might not gain significant survival benefits from induction chemotherapy. • Downstaging slight SBI NPC patients to T2 category would make a more accurate risk stratification, improve the predicting performance in OS, and have a better guidance in the use of IC for patients in advanced stage.

Dosimetric comparison between RapidArc and HyperArc techniques in salvage stereotactic body radiation therapy for recurrent nasopharyngeal carcinoma

Background

To evaluate dosimetric differences of salvage irradiations using two commercially available volumetric modulated arc therapy (VMAT) stereotactic body radiation therapy (SBRT) techniques: RapidArc (RA) and HyperArc (HA), for recurrent nasopharyngeal carcinoma (NPC) after initial radiation therapy.

Methods

Ten patients with recurrent NPC status previously treated with radiation therapy were considered suitable candidates for salvage SBRT using VMAT approach. Two separate treatment plans were created with HA and RA techniques for each case, with dosimetric outcomes compared with respect to tumor target coverage and organs-at-risk (OARs) sparing. Furthermore, the cumulative radiobiological effects to the relevant OARs from the original radiotherapy to the respective salvage SBRT plans were analyzed in terms of biologically effective dose (BED).

Results

Treatment with HA exhibited similar target dose coverage as with RA, while delivering a higher mean dose to the targets. Using RA technique, the mean maximal doses to optic apparatus and the mean brain dose were reduced by 1 to 1.5 Gy, comparing to HA technique. The conformity index, gradient radius, and intermediate dose spillage in HA plans were significantly better than those in RA. With HA technique, the volume of brain receiving 12 Gy or more was reduced by 44%, comparing to RA technique. The cumulative BEDs to spinal cord and optic apparatus with RA technique were 1 to 2 Gy₃ less than those with HA. HA technique significantly reduced the volume within body that received more than 100 Gy.

Conclusions

With better dose distribution than RA while maintaining sufficient target dose coverage, HA represents an attractive salvage SBRT technique for recurrent NPC.

Over-expression of cyclo-oxygenase-2 predicts poor survival of patients with nasopharyngeal carcinoma: a meta-analysis

OBJECTIVES

The conclusive prognostic significance of cyclo-oxygenase-2 has been determined in various cancers but not in nasopharyngeal carcinoma. Therefore, this study aimed to evaluate the relationship of cyclo-oxygenase-2 expression with the survival outcome and treatment response of nasopharyngeal carcinoma patients via a systematic meta-analysis approach.

METHODS

A meta-analysis was conducted in compliance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses ('PRISMA') checklist. The primary clinical characteristics of patients, and hazard ratios with 95 per cent confidence intervals of overall survival data, were tabulated from eligible studies. The relationship of cyclo-oxygenase-2 expression with survival outcome (expressed as hazard ratio) and treatment response (expressed as odds ratio) in nasopharyngeal carcinoma patients was analysed, and explained with the aid of forest plot charts.

RESULTS AND CONCLUSION

The pooled hazard ratio for overall survival was 2.02 (95 per cent confidence interval = 1.65-2.47). This indicates that the over-expression of cyclo-oxygenase-2 is significantly associated with the poor survival of nasopharyngeal carcinoma patients. The pooled odds ratio of 0.98 (95 per cent confidence interval = 0.27-3.49) reveals that over-expression of cyclo-oxygenase-2 was not significantly related to the treatment outcome.

Superiority of intensity-modulated radiation therapy in nasopharyngeal carcinoma with skull-base invasion

PURPOSE

To compare the clinical results and functional outcomes between two-dimensional conventional radiation therapy (2DRT) and intensity-modulated radiation therapy (IMRT) in nasopharyngeal carcinoma (NPC) with skull-base invasion.

METHODS

A total of 1258 patients were subclassified into two groups: mild skull-base invasion group (792; 63%) and severe skull-base invasion group (466; 37%). Patients were pair matched (1:1 ratio) using six clinical factors into 2DRT or IMRT groups. The Kaplan-Meier method and Cox regression model were performed to assess overall survival (OS), disease-free survival (DFS), locoregional relapse-free survival (LRRFS) and distant metastasis-free survival (DMFS). Toxicities were evaluated.

RESULTS

IMRT significantly improved four-year OS compared with 2DRT (65.6% vs. 81.8%, P = 0.000), DFS (57.3% vs. 73.3%, P = 0.000) and LRRFS (76.5% vs. 87.5%, P = 0.003) in NPC with severe skull-base invasion, but similar results were observed in patients with mild skull-base invasion (P > 0.05). In patients with severe invasion, radiation therapy techniques were found to be an independent prognostic factor for OS (HR = 0.457, P = 0.000), DFS (HR = 0.547, P = 0.000) and LRRFS (HR = 0.503, P = 0.004). IMRT was associated with better OS. In subgroups analysis, IMRT group also had a better survival in OS, DFS (P < 0.05 for all rates) for patients received concurrent chemotherapy and sequential chemotherapy compared to 2DRT in the severe invasion group. The IMRT group displayed lower incidence of mucositis, xerostomia, trismus (< 1 cm) and temporal lobe necrosis than the 2DRT group.

CONCLUSIONS

IMRT significantly improved patient survival compared with 2DRT in NPC patients with severe skull-base invasion, but a similar survival rate was noted in mild invasion patients. Chemotherapy can improve survival in NPC patients with severe invasion. Among the two therapies, IMRT significantly decreased therapy-related toxicity.

Safety and Effectiveness of De-escalated Radiation Dose in T1-3 Nasopharyngeal Carcinoma: A Propensity Matched Analysis

Backgrounds: With the excellent local control in T1 to T3 nasopharyngeal carcinoma (NPC) treated with intensity modulated radiotherapy (IMRT), the importance of toxicities is increasingly being recognised. This retrospective propensity score analysis sought to assess whether moderate dose reduction compromised long-term outcome compared with standard dose in T1-3 NPCs.

Materials and Methods: A total of 266 patients (67 female, 199 male) with a median age of 50 years between June 2011 and June 2015 were analysed. All were treated with IMRT, with or without systemic chemotherapy. The prescription radiation dose to gross tumor is 70Gy/2.12Gy/33F in our institution.

Results: With a median follow-up time of 50 months, the 5-year loco-regional failure-free survival (LRFS) and overall survival (OS) were 93.5% and 81.8%, respectively. 32 patients received radiation dose less than prescription dose, with a median dose of 63.6Gy (53-67Gy). Another 234 patients received exactly the prescription dose of 70Gy. Propensity scores were computed (32 patients treated with de-escalated dose and 64 patients with standard dose), there was no significant difference in 5-year LRFS and 5-year OS between the two groups (92.5% and 91.7% with standard dose; 82.1% and 85.7% with de-escalation dose; p=0.863 for LRFS and 0.869 for OS). No independent prognostic factor was associated with loco-regional failure in univariate analysis.

Conclusions: T1-3 nasopharyngeal carcinoma presenting with superior locoregional control, a moderately reduced dose (about 10%) delivered with IMRT resulted in comparable prognosis to those with prescription dose of 70Gy.

Comparison of the seventh and eighth editions of the UICC/AJCC staging system for nasopharyngeal carcinoma: analysis of 1317 patients treated with intensity-modulated radiotherapy at two centers

Background

In the intensity-modulated radiotherapy (IMRT) era, great improvement has been made in survival of nasopharyngeal carcinoma (NPC). The 7th edition of the International Union against Cancer/American Joint Committee on Cancer (UICC/AJCC) staging system seems “outdated ” as it mainly based on the study in 2D/3D era, and thus the 8th edition has made some amendments according to recent studies. We aimed to compare and evaluate these two editions of staging system for NPC in patients treated with intensity-modulated radiotherapy.

Methods

A total of 1317 patients with biopsy-proven, non-metastatic NPC treated with IMRT between 2009 and 2014 at two institutions were retrospectively assessed. All patients were assessed by magnetic resonance imaging and restaged according to the 7th and 8th editions. Prognostic factors for local relapse-free survival (LRFS), distant metastasis-free survival (DMFS), disease-free survival (DFS) and overall survival (OS) were assessed and compared using the Kaplan-Meier method and log-rank test. The Cox proportional hazards model was also used to calculate the hazard ratio (HR).

Results

In both 7th and 8th edition, insignificant difference could be observed between T2 and T3 disease, T2 and T4 disease (all P > 0.05) for LRFS, while the difference of LRFS between T3 and T4 disease was significant in the previous edition (P = 0.001) but insignificant (P = 0.279) after revision. For OS, highly similar survival curve could be seen between T2 and T3 disease in both edition (all P > 0.1). DMFS and OS were not significantly different between N3a and N1-3b categories of the 7th edition (all P > 0.05). In contrast, obvious segregation was observed between N3 and the other N categories after the revision and combination in the 8th edition (all P < 0.05). DFS and OS were not significantly different between stage IVA and IVB of the 7th edition (P = 0.057 and P = 0.365, respectively); therefore, combining these stages in the 8th edition was reasonable.

Conclusion

The overall stages and N categories of the 8th edition of the UICC/AJCC staging system provide better segregation of survival outcomes than the 7th edition. The 8th edition is also more clinically applicable as it has reduced ambiguity and revised out-of-date definitions. However, the T categories need further optimizing as the 8th edition failed to solve the problem of similar survival between adjacent T-classification, which has been exited since 7th edition.

Outcome and long-term efficacy of four facio-cervical fields conformal radiotherapy for nasopharyngeal carcinoma

Purpose

To evaluate the outcomes of 255 patients with nasopharyngeal carcinoma (NPC) treated with four facio-cervical fields conformal radiotherapy (4F-CRT).

Results

In one patient's 3 different RT treatment modalities, the 4F-CRT techniques resulted in sharper of the dose-volume histograms (DVHs) for primary gross tumor volume (PGTVnx) and planning target volume (PTVnx), similar to the intensity modulated radiation therapy (IMRT). The median follow-up duration was 43 months. Locoregional relapse and distant metastases as the first treatment failure events occurred in 32 (32/255, 12.5%) and 20 (30/255, 11.8%) patients, respectively. The 3-year and 5-year local control, disease-free survival, and overall survival rates were 83.3%, 82%, 83.8%, and 76.1%, 73.2%, 76.3% respectively. Univariate analysis displayed that clinical stage, T-stage, N-stage, and tumor response were related to prognosis. Multivariate analysis indicated that age, T-stage, N-stage, and combined chemotherapy were independent prognosticators. The incidence of grade 1–2 acute mucositis and leukocytopenia were 93.7% and 91.0%, respectively, with no cases of grade 4 toxicity detected.

Materials and Methods

From November 2007 to December 2011, 255 patients with histologically diagnosed, non-metastatic NPC were enrolled into this study and received 4F-CRT. Magnetic resonance imaging scans of the nasopharynx were performed on every patient. All patients received definitive radiotherapy with 6 MV X-rays using conventional fractions at 2 Gy daily, 5 fractions per week, and 231 patients with stage IIb-IV received concurrent chemotherapy and cisplatin-based adjuvant chemotherapy. The accumulated survival was calculated according to the Kaplan-Meier method; the log-rank test was used to compare survival differences. Multivariate analysis was performed using Cox's proportional hazard model.

Conclusions

Compared with the conventional treatment plans, the 4F-CRT plan delivered more dose to cover the tumor volume and reduces the doses of the normal tissues including the parotid gland, TMJs and so on. The long-term efficacy of 4F-CRT is satisfactory and its toxicities are tolerable.

Regionally Advanced Nasopharyngeal Carcinoma: Long-Term Outcome after Sequential Chemotherapy and Radiotherapy

Aims and background

To evaluate the long-term clinical outcome of 61 patients with regionally advanced nasopharyngeal carcinoma treated with sequential chemotherapy and radiotherapy within a phase II trial.

Methods

The trial evaluated a combined modality regimen including 3 cycles of induction polychemotherapy (epirubicin 70 mg/m2 d1, and cisplatin 100 mg/m2 d1, both recycled every 3 weeks) followed by definitive radiotherapy to the primary site (64–70 Gy) and the neck (50–70 Gy). Patients included in the trial had pathologically confirmed nasopharyngeal carcinoma; stage (UICC 1987) T-any, N2-3, M0; ECOG performance status 0–1. Sixty-one patients were enrolled between 1990 and 1996; stage according to UICC 1997 was IIb in 8%, III in 36% and IV in 56% of the patients; histology was WHO type 1–2 in 11% and WHO type 3 in 89% of cases. Minimum follow-up of 33 surviving patients is 5.2 years.

Results

Clinical failure has been observed in 30 patients (49%): initial failure, observed within the third year of follow-up in all but one case, was local alone in 6 (20%), regional alone in 10 (33%), local and regional in 1 (3%), regional and distant in 1 (3%), and distant alone in 12 patients (40%). Seven patients received salvage surgery to the neck, 2 of them still disease-free at 10 and 11 years from salvage surgery; 4 patients with an isolated local relapse were re-irradiated, and one of them was alive and well at 6.5 years from salvage radiation. At 5-year local control, regional control and distant metastasis-free rates were 83%, 74% and 73%, respectively; overall and disease-free survival were 64% and 51%. Late effects of initial treatment, as evaluated in 30 patients surviving 5 years without relapse, were generally acceptable, but some degree of xerostomia, dental damage, trismus and hearing loss were reported by a significant proportion of patients (respectively 100%, 88%, 76% and 86%).

Conclusions

In our experience, long-term clinical cure of regionally advanced nasopharyngeal carcinoma was obtained in 51% of cases treated with chemotherapy and radiotherapy. Salvage treatments (neck surgery, local re-irradiation) are worthy, as they increase the cure rate by approximately 10%, raising 5-year survival to over 60%. Late effects are significant, calling for refinements in radiation technique, better integration with chemotherapy to possibly decrease the need for higher radiation dose, and/or use of effective radioprotectants.

Old age at diagnosis increases risk of tumor progression in nasopharyngeal cancer

Age at diagnosis has been found to be a prognostic factor of outcomes in various cancers. However, the effect of age at diagnosis on nasopharyngeal cancer (NPC) progression has not been explored. We retrospectively evaluated the relationship between age and disease progression in 3,153 NPC patients who underwent radiotherapy, chemotherapy, or chemoradiotherapy between 2007 and 2009. Patients were randomly assigned to either a testing cohort or a validation cohort by computer-generated random assignment. X-tile plots determined the optimal cut-point of age based on survival status to be ≤61 vs. >61 years. Further correlation analysis showed that age >61 years was significantly correlated with the tumor progression and therapeutic regimen in both testing and validation cohorts (P <0.05). In the present study, we observed that older age (>61 years) was a strong and independent predictor of poor disease-free survival (DFS) and cancer-specific survival (CSS), in both univariate and multivariate analyses. Age was also found to be a significant prognostic predictor as well (P <0.05) when evaluating patients with the same disease stage. ROC analysis confirmed the predictive value of age on NPC-specific survival in both cohorts (P <0.001) and suggested that age may improve the ability to discriminate outcomes in NPCs, especially regarding tumor progression. In conclusion, our study suggests that older age at NPC diagnosis is associated with a higher incidence of tumor progression and cancer-specific mortality. Age is a strong and independent predictor of poor outcomes and may allow for more tailored therapeutic decision-making and individualized patient counseling.

Clinical Analysis of Recurrence Patterns in Patients With Nasopharyngeal Carcinoma Treated With Intensity-Modulated Radiotherapy

OBJECTIVE

To evaluate the characteristics and risk factors for locoregional recurrence in patients with nasopharyngeal carcinoma (NPC) treated with intensity-modulated radiotherapy (IMRT).

METHODS

The clinical diagnosis and treatment data of 195 patients with NPC treated with IMRT from March 2005 to May 2010 (including 9, 24, 70, and 92 cases of stage I, II, III, and IV disease, respectively, according to the 7th edition American Joint Committee on Cancer staging criteria) were retrospectively analyzed. The Kaplan-Meier method was used for survival analysis, and logistic regression was used to conduct univariate and multivariate analyses.

RESULTS

The 5-year recurrence rate was 10.8%, and the 5-year local and regional recurrence rates were 8.7% and 3.4%, respectively. Multivariate analysis showed that the short axis of the cervical lymph nodes (≥3 cm) was an influencing factor for regional lymph node recurrence after IMRT.

CONCLUSION

In-field and high-dose region failures were the main patterns associated with local-regional recurrence, and nasopharyngeal recurrence was most commonly detected. Newly diagnosed patients with large cervical lymph nodes (short diameter ≥3 cm) should be carefully followed up considering regional lymph node recurrence.

Induction chemotherapy followed by concurrent chemoradiotherapy vs. concurrent chemoradiotherapy for locoregionally advanced nasopharyngeal carcinoma: a retrospective cohort study

PURPOSE

To evaluate the efficacy and toxicity of induction chemotherapy followed by concurrent chemoradiotherapy vs. concurrent chemoradiotherapy for locoregionally advanced nasopharyngeal carcinoma (NPC).

METHODS

We reviewed data of locoregionally advanced NPC patients who underwent 2 different treatment plans, 1 with induction chemotherapy followed by concurrent chemoradiotherapy (IC + CCRT) and the other with only concurrent chemoradiotherapy (CCRT). All patients received cisplatin 80 mg/m² 3 weeks one cycle concurrently with intensity-modulated radiation therapy, and three IC protocols were included for the IC + CCRT group.

RESULTS

Data of 262 patients treated from May 2011 to November 2014 were found eligible for our study. With a median follow-up of 29.02 months, no significant differences were detected between the two groups on the 2-year overall survival or OS rates (96.63 vs. 92.86%, P = 0.169), 2-year distant metastasis-free survival or DMFS rates (91.57 vs. 86.90%, P = 0.246) and 3-year DMFS rates (90.45 vs. 82.14%, P = 0.093). However, they were statistically different on 2-year locoregional failure-free survival or LFFS rates (94.94 vs. 86.90%, P = 0.020), 3-year OS rates (95.51 vs. 82.14%, P = 0.002) and 3-year LFFS rates (93.82 vs. 79.76%, P = 0.001). The most common severe (grade 3-4) adverse events we recorded were Nausea/vomiting (36.52 vs. 33.33%), leukopenia (14.04 vs. 4.76%), thrombocytopenia (3.93 vs. 3.57%) and hepatic toxicity (3.37 vs. 2.38%).

CONCLUSION

Compared with CCRT, the treatment plan IC + CCRT produced significantly encouraging outcomes in locoregionally advanced NPC patients on local progression-free survival and 3-year overall survival position, but might raise the risk of certain adverse reactions.

EMP2 re-expression inhibits growth and enhances radiosensitivity in nasopharyngeal carcinoma

Although radiation therapy is the primary treatment for nasopharyngeal carcinoma, radioresistance remains a major obstacle to successful treatment in many cases, and the exact underlying molecular mechanisms are still ill-defined. EMP2, epithelial membrane protein-2, was a recently identified potential oncogene involved in multiple biological processes including cell migration and cell proliferation. This study was to explore the potential relationship between EMP2 expression, nasopharyngeal carcinoma genesis, and radioresistance. EMP2 expression status in 98 nasopharyngeal carcinoma clinical samples was examined by immunohistochemical staining. As a result, most of the nasopharyngeal carcinoma tumor samples were weakly or negatively stained, while paired adjacent normal tissues were moderately or strongly stained. Moreover, patients with higher expression of EMP2 had significant longer survival times. EMP2 re-expression suppresses cell growth, induces S-phase cell cycle arrest, and promotes radiosensitivity and apoptosis in nasopharyngeal carcinoma cells. These results support that loss of EMP2 is common, and its re-expression may serve as an approach to enhance radiation sensitivity in nasopharyngeal carcinoma.

Prognostic factors and failure patterns in non-metastatic nasopharyngeal carcinoma after intensity-modulated radiotherapy

Background

The prognostic values of staging parameters require continual re-assessment amid changes in diagnostic and therapeutic methods. This study aimed to identify the prognostic factors and failure patterns of non-metastatic nasopharyngeal carcinoma (NPC) in the intensity-modulated radiotherapy (IMRT) era.

Methods

We reviewed the data from 749 patients with newly diagnosed, biopsy-proven, non-metastatic NPC in our cancer center (South China, an NPC endemic area) between January 2003 and December 2007. All patients underwent magnetic resonance imaging (MRI) before receiving IMRT. The actuarial survival rates were estimated using the Kaplan–Meier method, and survival curves were compared using the log-rank test. Multivariate analyses with the Cox proportional hazards model were used to test for the independent prognostic factors by backward eliminating insignificant explanatory variables.

Results

The 5-year occurrence rates of local failure, regional failure, locoregional failure, and distant failure were 5.4, 3.0, 7.4, and 17.4%, respectively. The 5-year survival rates were as follows: local relapse-free survival, 94.6%; nodal relapse-free survival, 97.0%; distant metastasis-free survival, 82.6%; disease-free survival, 75.1%; and overall survival, 82.0%. Multivariate Cox regression analysis revealed that orbit involvement was the only significant prognostic factor for local failure (P = 0.011). Parapharyngeal tumor extension, retropharyngeal lymph node involvement, and the laterality, longest diameter, and Ho’s location of the cervical lymph nodes were significant prognostic factors for both distant failure and disease failure (all P < 0.05). Intracranial extension had significant prognostic value for distant failure (P = 0.040).

Conclusions

The key failure pattern for NPC was distant metastasis in the IMRT era. With changes in diagnostic and therapeutic technologies as well as treatment modalities, the significant prognostic parameters for local control have also been altered substantially.

CT-diagnosed severe skull base bone destruction predicts distant bone metastasis in early N-stage nasopharyngeal carcinoma

Bone metastasis is the most frequent type of distant metastasis in nasopharyngeal carcinoma (NPC). In this study, we investigated the correlation between the skull base bone destruction and the distant bone metastasis in patients with NPC. A total of 449 cases with NPC who were diagnosed and had definitive radiotherapy from 2001 to 2006 were enrolled in this study. The skull base bone destruction was diagnosed by computed tomography (CT) in all cases, and 191 patients also underwent magnetic resonance imaging scan. Kaplan–Meier method was adopted to perform the univariate analysis; Cox regression model was used to perform multivariate analysis to determine whether the skull base bone destruction when diagnosed by CT was an independent impact factor of the distant bone metastases. The group with skull base bone destruction had a distant bone metastases rate of 9.0% (14/155), whereas the group without skull base bone destruction had rate of 4.1% (12/294). The multivariate analysis showed that the skull base bone destruction, when diagnosed by CT, was an independent impact factor of the distant bone metastases-free survival in the early N-staging cases, but was not an independent impact factor when diagnosed by MRI. The skull base bone destruction diagnosed by CT in patients with NPC had predictive value for the distant bone metastases, especially for the early N-staging cases.

Downregulation of Annexin A1 is correlated with radioresistance in nasopharyngeal carcinoma

Radiotherapy is the primary treatment for nasopharyngeal carcinoma (NPC), but radioresistance often remains an obstacle to successful treatment. In our previous study, it was demonstrated that Annexin A1 (ANXA1) was involved in the p53-mediated radioresponse in NPC cells, which suggested that it may be associated with radioresistance in NPC; however, the role of ANXA1 in NPC radioresistance is unknown. In the present study, CNE2 cells were stably transfected with pLKO.1-ANXA1-small hairpin (sh)RNAs to investigate the effects of ANXA1 on the radiosensitivity of NPC. CNE2 cells transfected with pLKO.1 were used as the control. The radiosensitivities of the cells in vitro were analyzed using the clonogenic survival assay, cell growth analysis, flow cytometry and Hoechst 33258 staining. ANXA1 downregulation significantly enhanced clonogenic survival and cell growth following treatment of CNE2 cells with ionizing radiation (IR), increased the number of cells in the S phase and decreased IR-induced apoptosis. These results suggested that the radiosensitivity of CNE2 cells transfected with ANXA1-specific shRNA was significantly lower compared with the control cells. Therefore, ANXA1 downregulation may be involved in the radioresistance of NPC, and ANXA1 may be considered a novel biomarker for predicting NPC response to radiotherapy.

Treatment outcomes and late toxicities of 869 patients with nasopharyngeal carcinoma treated with definitive intensity modulated radiation therapy: new insight into the value of total dose of cisplatin and radiation boost

This study was to report the long-term outcomes and toxicities of nasopharyngeal carcinoma (NPC) treated with intensity-modulated radiation therapy (IMRT). From 2009 to 2010, 869 non-metastatic NPC patients treated with IMRT were retrospectively enrolled. With a median follow-up of 54.3 months, the 5-year estimated local recurrence-free survival (LRFS), regional recurrence-free survival (RRFS), distant metastasis-free survival (DMFS), disease-free survival (DFS) and overall survival (OS) were 89.7%, 94.5%, 85.6%, 76.3%, 84.0%, respectively. In locally advanced NPC, gender, T, N, total dose of cisplatin more than 300 mg/m(2) and radiation boost were independent prognostic factors for DMFS and DFS. Age, T, N and total dose of cisplatin were independent prognostic factors for OS. Radiation boost was an adverse factor for LRFS, RRFS, DMFS and DFS. Concurrent chemotherapy was not an independent prognostic factor for survival, despite marginally significant for DMFS in univariate analysis. Concurrent chemotherapy increased xerostomia and trismus, while higher total dose of cisplatin increased xerostomia and otologic toxicities. In conclusion, IMRT provided satisfactory long-term outcome for NPC, with acceptable late toxicities. Total dose of cisplatin was a prognostic factor for distant metastasis and overall survival. The role of concurrent chemotherapy and radiation boost in the setting of IMRT warrants further investigation.

Tumor Regression and Patterns of Distant Metastasis of T1-T2 Nasopharyngeal Carcinoma with Intensity-Modulated Radiotherapy

Purpose

To study tumor regression and failure patterns in T1-T2 non-metastatic nasopharyngeal carcinoma (NPC) after intensity-modulated radiotherapy (IMRT).

Methods

A retrospective analysis of 139 nasopharyngeal carcinoma patients treated with IMRT between January 2005 and December 2010 in our center was performed. According to the AJCC staging system, all primary lesions were attributed to T1 and T2. The prescription doses were 66 Gy at 30 fractions to gross tumor volume of the nasopharynx and the positive neck nodes, 60 Gy to high-risk clinical target volume and 54 Gy to low-risk clinical target volume. Patients staged III, IV A/B or II (lymph node measured 4 cm or more in diameter) received platinum-based chemotherapy.

Results

By the end of radiotherapy, 7.2% (10/139), 23.7% (33/139), and 9.4% (13/139) of patients had residual lesions in the nasopharynx, cervical lymph nodes and retropharyngeal lymph nodes, respectively. The majority of patients had complete remission within 6 months of radiotherapy completion. Five months after IMRT, three patients with residual tumors in the cervical lymph nodes underwent surgery. Among these patients, two patients had positive pathological findings, and one patient had negative findings. With a median follow-up of 59 months, the 5-year overall survival, local control, regional control and distant metastasis-free rates were 87.8%, 96.7%, 94.9% and 89.1%, respectively. Fifteen patients developed distant metastases, representing the primary failure pattern.

Conclusions

Most residual lesions that persisted after IMRT vanished completely in six months. Considering the potential damage to normal structures, clinicians should be cautious when considering the use of boost irradiation after radiotherapy. Distant metastasis was the primary cause of treatment failure, which was significantly higher in N2-3 patients than in N0-1. Additional studies to better understand distant metastases are needed.

Ethanolic Extracts of Pluchea indica Induce Apoptosis and Antiproliferation Effects in Human Nasopharyngeal Carcinoma Cells

Pluchea indica is used in traditional medicine for the treatment of lumbago, ulcer, tuberculosis and inflammation. The anti-cancer activities and the underlying molecular mechanisms of the ethanolic extracts of P. indica root (PIRE) were characterized in the present study. PIRE strongly inhibited the viability of the human nasopharyngeal carcinoma cells (NPC-TW 01 and NPC-TW 04) in a time- and dose-dependent manner. Migration of cancer cells was also suppressed by PIRE. In addition, PIRE significantly increased the occurrence of the cells in sub-G1 phase and the extent of DNA fragmentation in a dose-dependent manner, which indicates that PIRE significantly increased apoptosis in NPC cells. The apoptotic process triggered by PIRE involved up-regulation of pro-apoptotic Bax protein and down-regulation of anti-apoptotic Bcl-2 protein, consequently increasing the ratios of Bax/Bcl-2 protein levels. Moreover, the p53 protein was up-regulated by PIRE in a concentration-dependent manner. Therefore, PIRE could induce the apoptosis-signaling pathway in NPC cells by activation of p53 and by regulation of apoptosis-related proteins.

Clinical Outcome among Nasopharyngeal Cancer Patients in a Multi-Ethnic Society in Singapore

Background

Nasopharyngeal cancer (NPC) is endemic among Chinese populations in Southeast Asia. However, the outcomes of non-Chinese NPC patients in Singapore are not well reported.

Aim

To determine if non-Chinese NPC patients have a different prognosis and examine the clinical outcomes of NPC patients in a multi-ethnic society.

Methods

Retrospective chart review of 558 NPC patients treated at a single academic tertiary hospital from 2002 to 2012. Survival and recurrence rates were analysed and predictive factors identified using the Kaplan-Meier method and Cox regression model.

Results

Our cohort comprised 409 males (73.3%) and 149 females (26.7%) with a median age of 52 years. There were 476 Chinese (85.3%), 57 Malays (10.2%), and 25 of other ethnic groups (4.5%). Non-Chinese patients were more likely to be associated with advanced nodal disease at initial presentation (p = 0.049), compared with the Chinese. However, there were no statistical differences in their overall survival (OS) or disease specific survival (DSS) (p = 0.934 and p = 0.857 respectively). The 3-year and 5-year cohort OS and DSS rates were 79.3%, 70.7%, and 83.2%, 77.4% respectively. Advanced age (p<0.001), N2 disease (p = 0.036), N3 disease (p<0.001), and metastatic disease (p<0.001) at presentation were independently associated with poor overall survival. N2 disease (p = 0.032), N3 disease (p<0.001) and metastatic disease (p<0.001) were also independently associated with poor DSS. No predictive factors were associated with loco-regional recurrence after definitive treatment. Advanced age (p = 0.044), N2 disease (p = 0.033) and N3 disease (p<0.001) were independently associated with distant relapse.

Conclusion

In a multi-ethnic society in Singapore, non-Chinese are more likely to present with advanced nodal disease. This however did not translate into poorer survival outcomes. Older patients with N2 or N3 disease are associated with a higher risk of distant relapse and poor overall survival.

Suggestions for lymph node classification of UICC/AJCC staging system: a retrospective study based on 1197 nasopharyngeal carcinoma patients treated with intensity-modulated radiation therapy

This article provides suggestions for N classification of Union for International Cancer Control/American Joint Committee on Cancer (UICC/AJCC) staging system of nasopharyngeal carcinoma (NPC), purely based on magnetic resonance imaging (MRI) in intensity-modulated radiation therapy (IMRT) era.A total of 1197 nonmetastatic NPC patients treated with IMRT were enrolled, and all were scanned by MRI at nasopharynx and neck before treatment. MRI-based nodal variables including level, laterality, maximal axial diameter (MAD), extracapsular spread (ECS), and necrosis were analyzed as potential prognostic factors. Modifications of N classification were then proposed and verified.Only nodal level and laterality were considered to be significant variables affecting the treatment outcome. N classification was thus proposed accordingly: N0, no regional lymph node (LN) metastasis; N1, retropharyngeal LNs involvement (regardless of laterality), and/or unilateral levels I, II, III, and/or Va involvement; N2, bilateral levels I, II, III, and/or Va involvement; and N3, levels IV, Vb, and Vc involvement. This proposal showed significant predicting value in multivariate analysis. N3 patients indicated relatively inferior overall survival (OS) and distant metastasis-free survival (DMFS) than N2 patients; however, the difference showed no statistical significance (P = 0.673 and 0.265 for OS and DMFS, respectively), and this was considered to be correlated with the small sample sizes of N3 patients (79 patients, 6.6%).Nodal level and laterality, but not MAD, ECS, and necrosis, were considered to be significant predicting factors for NPC. The proposed N classification was proved to be powerfully predictive in our cohort; however, treatment outcome of the proposed N2 and N3 patients could not differ significantly from each other. This insignificance may be because of the small sample sizes of N3 patients. Our results are based on a single-center data, to develop a new N classification that is universally acceptable; further verification by data from multicenter is warranted.

The impact of reduced-volume, intensity-modulated radiation therapy on disease control in nasopharyngeal carcinoma

Objective

To investigate the feasibility of using intensity-modulated radiotherapy (IMRT) with reduced, high-dose target volumes for nasopharyngeal carcinoma (NPC).

Methods

The first 57 patients (admitted from October 2005 to May 2008) were treated with large-target-volume IMRT (LV-IMRT). For the LV-IMRT group, the CTV at 70 Gy (CTV70) was delineated as the gross target volume (GTV) plus 7mm, with or without the first-echelon lymph-node region. The next 56 patients (admitted from June 2008 to November 2011) were treated with reduced-target-volume IMRT (RV-IMRT). For the RV-IMRT group, the CTV70 was delineated as the GTV alone.

Results

The 4-year local recurrence-free, regional recurrence-free, distant metastasis-free, progression-free, and overall survival rates were 77.2%, 80.1%, 83.2%, 61.2%, and 74.4% for the LV-IMRT group and 83.5%, 92.6%, 89.1%, 78.5, and 91.0% for the RV-IMRT group, respectively. Late toxicity scoring of xerostomia was lesser in the RV-IMRT group than the LV-IMRT group (P < 0.001).

Conclusions

The use of RV-IMRT for the treatment of NPC did not negatively affect survival rates but did reduce the late xerostomia events compared to LV-IMRT.

Prognostic value of classifying parapharyngeal extension in nasopharyngeal carcinoma based on magnetic resonance imaging

Purpose. To subclassify parapharyngeal extension in nasopharyngeal carcinoma (NPC) and investigate its prognostic value and staging categories based on magnetic resonance imaging (MRI). Methods and Materials. Data from 1504 consecutive NPC patients treated with definitive-intent radiotherapy were analyzed retrospectively. Sites of parapharyngeal extension were defined by MRI. Overall survival (OS), local relapse-free survival (LRFS), and distant metastasis-free survival (DMFS) were calculated by the Kaplan-Meier method and compared with the log-rank test. Hazard consistency and hazard discrimination were determined by multivariate analysis with Cox proportional hazards models. Results. 1104 patients (73.4%) had parapharyngeal extension; 1.7–63.8% had involvement of various anatomic sites. The hazard ratio for death was significantly higher with extensive parapharyngeal extension (lateral pterygoid muscle of masticator space and beyond or parotid space) than with mild extension (medial pterygoid muscle of masticator space, or carotid, prestyloid, and prevertebral or retropharyngeal space). OS, LRFS, and DMFS with extensive parapharyngeal extension were similar to those in T4 disease; OS, LRFS, and DMFS with mild parapharyngeal extension were significantly higher than in those T3 disease (all P ≤ 0.015). Conclusions. Parapharyngeal extension in NPC should be subclassified as mild or extensive, which should be regarded as stages T2 and T4 diseases, respectively.

Role of Chemotherapy in Stage II Nasopharyngeal Carcinoma Treated with Curative Radiotherapy

Purpose

To define the role of neoadjuvant and concurrent chemotherapy in stage II nasopharyngeal carcinoma, we compared the treatment outcomes of patients treated with curative radiotherapy with or without chemotherapy.

Materials and Methods

From 2004 to 2011, 138 patients with American Joint Committee on Cancer (AJCC) 2002 stage II nasopharyngeal carcinoma were treated with curative radiotherapy in 12 hospitals in South Korea. Treatment methods included radiotherapy alone in 34 patients, neoadjuvant chemotherapy followed by radiotherapy alone in seven, concurrent chemoradiotherapy in 80, and neoadjuvant chemotherapy followed by concurrent chemoradiotherapy in 17. Adjuvant chemotherapy was used in 42 patients. Total radiation dose ranged from 64 Gy to 74.2 Gy (median, 70 Gy).

Results

Median follow-up was 48 months (range, 7 to 97 months) for all patients. At the last follow-up, 13 patients had died and 32 had experienced treatment failure; locoregional failure occurred in 14, distant failure in 16, and both in two. Five-year locoregional relapse-free survival, distant metastasis-free survival, progression-free survival, and overall survival were 86.2%, 85.5%, 74.4%, and 88.2%, respectively. Multivariate analyses showed that the significant prognostic factors were concurrent chemotherapy and N stage for locoregional relapse-free survival, concurrent chemotherapy for progression-free survival, and age and N stage for overall survival. Neither neoadjuvant nor concurrent chemotherapy improved distant metastasis-free survival.

Conclusion

Concurrent chemotherapy significantly improved 5-year locoregional relapse-free survival and progression-free survival in stage II nasopharyngeal carcinoma. However, neoadjuvant chemotherapy failed to improve either.

Prognostic model for distant metastasis in locally advanced nasopharyngeal carcinoma after concurrent chemoradiotherapy

BACKGROUND

A prognostic model should be established for distant metastasis in locally advanced nasopharyngeal carcinoma (NPC) after concurrent chemoradiotherapy (CCRT).

METHODS

Patients with locally advanced NPC who received CCRT were divided into a construction set (230 patients) and a validating set (115 patients). The constructed index was derived on the former and then tested on the latter.

RESULTS

The prognostic score was defined as the number of adverse prognostic factors: age >45, N3 category, hemoglobin <11.0 g/dL and lactate dehydrogenase ≥240 U/L. The score predicted the 5-year distant metastasis-free survival as follows: 0, 91%; 1, 74%; 2, 51%; and ≥3, 12%. In the validating set, the observed 5-year distant metastasis-free survival of these 4 groups with scores of 0, 1, 2, 3, or higher were 81%, 68%, 47%, and 15%, respectively.

CONCLUSION

The established model might be useful for predicting the risk of distant metastasis in patients with locally advanced NPC who underwent CCRT and may identify the patients' need for intensified adjuvant chemotherapy.

Is replacement of the supraclavicular fossa with the lower level classification based on magnetic resonance imaging beneficial in nasopharyngeal carcinoma?

PURPOSE AND OBJECTIVES

To investigate the pattern of lymph node metastasis and treatment outcome after intensity-modulated radiotherapy (IMRT) in nasopharyngeal carcinoma (NPC), and assess the possibility of replacing Ho's supraclavicular fossa (SCF) with the lower level (LL; cervical extension below caudal edge of cricoid cartilage) based on magnetic resonance imaging (MRI) as a criterion for N3 disease.

METHODS AND MATERIALS

We retrospectively reviewed 749 patients with biopsy-proven non-metastatic NPC treated with IMRT. Lymph node metastasis was mapped using the 2013 International Consensus Guidelines.

RESULTS

Cervical lymph node (CLN) laterality, CLN greatest dimension (>60 vs. ⩽60 mm) and Ho's SCF were independent prognostic factors for disease-free survival (DFS) and distant metastasis-free survival (DMFS; P<0.01) in multivariate analysis. Replacing Ho's SCF with the LL was also predictive for DFS and DMFS (P<0.01). Compared to the 7th UICC/AJCC, N-categories based on the LL provided more satisfactory distinction between hazard ratios for distant and disease failure for each N-category. N3a and N3b as defined by the 7th UICC/AJCC had similar DMFS (P=0.31) and DFS (P=0.21).

CONCLUSIONS

Replacing Ho's SCF with the LL is simple and practical. The N-category staging system could be further simplified by merging N3 subcategories.

Clinical outcomes and prognostic factors of 695 nasopharyngeal carcinoma patients treated with intensity-modulated radiotherapy

OBJECTIVE

The 5-year clinical outcomes and prognostic factors of nasopharyngeal carcinoma (NPC) patients treated with intensity modulated radiotherapy (IMRT) were evaluated.

METHODS

Six hundred ninety five NPC patients primarily treated with IMRT in Sichuan Cancer Hospital from January, 2003 to December, 2006 were analyzed retrospectively, including 540 males and 155 females. The prescription dose was delivered as follows: gross target volume (GTVnx) 67-76 Gy in 30-33 fractions, positive neck lymph nodes (GTVln-R/L) 60-70 Gy in 30-33 fractions, high-risk clinical target volume (CTV1) 60-66 Gy, low-risk clinical target volume (CTV2) 54-60 Gy, and clinical target volume of cervical lymph node regions (CTVln) 50-55 Gy.

RESULTS

The 5-year local control (LC), regional control, distant metastasis-free survival (DMFS), disease free survival, disease specific survival, and overall survival (OS) rates were 89.8%, 95.2%, 74.1%, 69.6%, 83.2%, and 77.1%. The 5-year DMFS of IMRT and IMRT combined with chemotherapy was 62.1% and 70.9%, the OS of them was 72.9% and 79.1%. The incidence of grade 3 acute and late toxicity was 38.3% and 4.2%, respectively.

CONCLUSION

The 5-year LC and OS rate of NPC treated with IMRT was 89.8% and 77.1%. The clinical stage, N stage, volume of GTVnx, and chemotherapy were the main prognostic factor for the OS. Distant metastasis was the main pattern of failure.

A meta-analysis on the EBV DNA and VCA-IgA in diagnosis of Nasopharyngeal Carcinoma

OBJECTIVE

We conducted a meta-analysis to compare the EBV DNA and VCA-IgA in diagnosis of Nasopharyngeal Carcinoma, and provide important evidence for screening method of NPC.

METHODOLOGY

Three databases, Medline (from Jan. 1966 to Jan. 2012), EMBASE (from January 1988 to Jan. 2012) and Chinese Biomedical Database (from January 1980 to Jan. 2012) were used to detect the role of EBV DNA and VCA-IgA in diagnosis of NPC. Meta-DiSc statistical software was used for analysis.

RESULTS

Twenty seven case-control and cohort studies were included in final analysis. A total of 1554 cases and 2932 controls were included in our meta-analysis. The Sensitivity specificity, positive likelihood (+LR) and likelihood negative (-LR) of EBV-DNA in diagnosis of NPC were 0.75(0.72-0.76), 0.87(0.85-0.88), 6.98(4.50-10.83) and 0.18(0.11-0.29), respectively, and they were 0.83(0.81-0.85), 0.85(0.83-0.86), 10.89(5.41-21.93) and 0.20(0.14-0.29) for VCA-IgA. The SROC for EBV DNA detection was 0.939, while this was 0.936 for VCA-IgA detection. The subgroup analysis showed EBV-DNA had larger areas under the summary receiver operator curve when compared with VCA-IgA in high quality and low quality studies.

CONCLUSION

Our meta-analysis indicated the EBV DNA had higher sensitivity and specificity in diagnosis of NPC.

Concurrent chemoradiotherapy followed by adjuvant chemotherapy compared with concurrent chemoradiotherapy alone for the treatment of locally advanced nasopharyngeal carcinoma: a retrospective controlled study

OBJECTIVE

We evaluated the survival benefit of providing concurrent chemoradiotherapy (ccrt) plus adjuvant chemotherapy compared with ccrt alone to patients with locally advanced nasopharyngeal carcinoma.

METHODS

This retrospective study included 130 patients with nasopharyngeal carcinoma treated with ccrt plus adjuvant chemotherapy from June 2005 to December 2010. Another 130 patients treated with ccrt alone during the same period were matched on age, sex, World Health Organization histology, T stage, N stage, and technology used for radiotherapy. The endpoints included overall survival, locoregional failure-free survival, distant metastasis failure-free survival, and failure-free survival.

RESULTS

At a mean follow-up of 42.1 months (range: 8-85 months), the observed hazard ratios for the group receiving ccrt plus adjuvant chemotherapy compared with the group receiving ccrt alone were: for overall survival, 0.77 [95% confidence interval (ci): 0.37 to 1.57]; for locoregional failure-free survival, 1.00 (95% ci: 0.37 to 2.71); for distant metastasis failure-free survival, 1.15 (95% ci: 0.56 to 2.37); and for failure-free survival, 1.26 (95% ci: 0.69 to 2.28). There were no significant differences in survival between the groups. After stratification by disease stage, ccrt plus adjuvant chemotherapy provided a borderline significant benefit for patients with N2-3 disease (hazard ratio: 0.35; 95% ci: 0.11 to 1.06; p = 0.052). Multivariate analyses indicated that only tumour stage was a prognostic factor for overall survival.

CONCLUSIONS

Patients with locally advanced nasopharyngeal carcinoma received no significant survival benefit from the addition of adjuvant chemotherapy to ccrt. However, patients with N2-3 disease might benefit from the addition of adjuvant chemotherapy to ccrt.

Retrospective analysis of results of treatment for nasopharyngeal carcinoma in Macao

BACKGROUND

Nasopharyngeal carcinoma (NPC) is a common malignancy in Southeast Asia, however, a full consensus has not yet been reached as to the value of comprehensive treatment for NPC. This study was designed to evaluate the epidemiological characteristics of NPC and their prognostic value, as well as the long-term efficacy of NPC treatment.

PATIENTS AND METHODS

A total of 248 patients, with different stages of NPC, were included in this study.

RESULTS

The 5-year overall survival (OS) rates for patients in stages I, II, III and IV were 90.48%, 76.71%, 76.89% and 33.87%, respectively (P=0.000), while the respective 5-year progression-free survival (PFS) rates were 85.15%, 72.36%, 63.88% and 26.26% (P=0.000). The respective 5-year OS rates, according to stage, for the group that received radiotherapy combined with chemotherapy and for the group that received radiotherapy only were as follows: stages I and II, 81.67% and 79.59% (P=0.753); stage III, 79.91% and 70.38% (P=0.143); stage IV, 35.22% and 0% (P=0.000). The respective 5-year PFS rates in these groups were as follows: stages I and II, 75.83% and 74.98% (P=0.814); stage III, 74.08% and 42.25% (P=0.027); stage IV, 27.31% and 0% (P=0.000).

CONCLUSIONS

Clinical staging appears to be the most important prognostic factor for NPC. As the stage number increases, both the 5-year OS and PFS significantly decrease. Adding chemotherapy to radiotherapy was not advantageous for patients with stage I or II NPC, however the addition of chemotherapy to radiotherapy significantly improved OS and PFS in patients with stage IV NPC. The addition of chemotherapy improved PFS, but not OS in patients with stage III NPC.

MR imaging prediction of local control of nasopharyngeal carcinoma treated with radiation therapy and chemotherapy

OBJECTIVE

To retrospectively evaluate the association of MRI findings with local control of nasopharyngeal carcinoma (NPC) treated with radiation therapy and chemotherapy (chemoradiotherapy).

METHODS

Pre-treatment MRIs of 101 patients (78 males and 23 females, 23-79 years of age) who had NPC treated with chemoradiotherapy were retrospectively reviewed to evaluate tumour involvement of nasopharyngeal anatomic subsites, tumour volume and MRI appearance. Local control rates were evaluated with respect to these MRI findings.

RESULTS

Univariate analysis (using the Kaplan-Meier method) showed that invasion of the skull base as determined by MRI was a significant predictor of local control. In terms of clinical characteristics, T stage and pathological subtype were significant predictors of local control. Multivariate analysis (Cox regression model) of the radiologic findings and clinical characteristics revealed that invasion of the skull base (p = 0.003) and pathological subtype (p < 0.001) were independent prognostic factors for local control.

CONCLUSION

Invasion of the skull base as determined by MRI predicts the likelihood of local failure and may be helpful in identifying a subset of patients with tumours at risk of local recurrence within 3 years after primary chemoradiotherapy.

ADVANCES IN KNOWLEDGE

It has now become common practice to use MRI for pre-treatment evaluation of patients with NPC. The potential role for MRI findings in predicting local control and prognosis in patients with NPC has implications for treatment planning.

[Radioanatomy of rhinopharyngeal carcinoma]

Rhinopharyngeal cancer is one of the best indications for conformal radiotherapy with modulated intensity. Due to the high dose gradient, accurate delineation of target volumes and organs at risk is a critical success factor with this technology. This requires a good knowledge of rhinopharyngeal radioanatomy and optimal imaging techniques.

Effectiveness and toxicities of intensity-modulated radiation therapy for patients with T4 nasopharyngeal carcinoma

Objective

To evaluate the effectiveness and toxicities in T4 nasopharyngeal carcinoma (NPC) using intensity-modulated radiotherapy (IMRT) combined with chemotherapy.

Methods

This is a retrospective analysis of 81 patients treated with intensity-modulated radiotherapy (IMRT). All the primary tumors were attributed to T4 stage according to the AJCC2010 staging system. And the distribution of disease by N stage was N0 in 13.6%, N1 in 30.9%, N2 in 37%, and N3 in 18.5%. Cisplatin-based chemotherapy was offered to all patients. Radiotherapy-related toxicities were graded according to the Acute and the Late Radiation Morbidity Scoring Criteria of the Radiation Therapy Oncology Group (RTOG) scoring criteria. Chemotherapy-related toxicities were graded by National Cancer Institute Common Toxicity Criteria (NCI-CTC) version 3.0. Prognostic factors were assessed by univariate analysis.

Results

With a median follow-up of 37 months, 12 patients experienced local regional failure and total distant metastasis occurred in 18 patients, representing the major mode of failure. Ten patients died. Among them, 70% died of distant metastasis. The 3-year actuarial rates of local failure–free survival (LFFS), regional failure–free survival (RFFS), distant failure–free survival (DFFS), overall survival (OS), and progression–free survival (PFS) were 83.8%, 97.4%, 81.3%, 90%, and 69.7%, respectively. Acute and late toxicities were mild or moderate.

Conclusions

IMRT provides excellent local-regional control for T4 NPC. Distant metastasis remains the major cause of treatment failure. Further explorations of the sequence and regimen of systemic therapy are needed in the future.

Aberrant CpG island methylation of PTEN is an early event in nasopharyngeal carcinoma and a potential diagnostic biomarker

The inactivation of phosphatase and tensin homolog (PTEN) due to its CpG island hypermethylation has been observed in some types of tumors except nasopharyngeal carcinoma (NPC). In the present study, we focused on the aberrant methylation of PTEN CpG islands in NPC. The mRNA expression of PTEN was detected by quantitative PCR in 45 NPC and 22 non-tumor nasopharyngeal epithelial (NP) tissues. The methylation status of PTEN was examined by methylation-specific polymerase chain reaction and sequencing. The mRNA expression of PTEN in three NPC cell lines treated with 5-aza-2'-deoxycytidine (5-aza-dC) was also examined. PTEN was downregulated in both NPC tissues and NPC cell lines and a relatively higher methylation level of PTEN was found in NPC specimens (82.2%) relative to NP tissues (5.3%). The PTEN mRNA expression was restored in NPC cell lines by treatment with 5-aza-dC. These results first reveal an epigenetic alteration, aberrant methylation of PTEN, in NPC, which is probably an early event and may be regarded as a novel candidate biomarker for early stage of NPC detection and prevention.

Preliminary results of nasopharyngeal carcinoma treated with intensity-modulated radiotherapy: a retrospective study of 364 patients

The aim of the study was to evaluate the survival and toxicity of 364 patients with nasopharyngeal carcinoma (NPC) treated by intensity-modulated radiotherapy (IMRT). Cisplatin-based chemotherapy was given to patients with local-regionally advanced disease. The median follow-up was 26 months (range 3-62 months). The 2-year local failure-free survival, regional failure-free survival (RFFS), distant metastasis-free survival (DMFS) and overall survival (OS) were 97.6, 96.8, 89.1 and 93.5 %, respectively. Overall disease failures (at any site) were found in 60 patients. Eighteen patients experienced locoregional failures: seven were local only, seven were regional only and four were both local and regional. Forty-two patients developed distant metastases. Of these, 30 patients had single organ metastasis and 12 had multiple organ metastases. The most common acute toxicities were dermatitis, mucositis and xerostomia. Grade 0-2 dermatitis, mucositis and xerostomia occurred in 337 patients (92.6 %), 204 patients (56.1 %) and 364 patients (100 %), respectively. Grade 3 dermatitis, mucositis and xerostomia were seen in 27 patients (7.4 %), 160 patients (44 %) and 0 patients. No Grade 4 acute toxicities were observed. N stage was an independent prognostic factor for RFFS, DMFS and OS. Our preliminary results showed that IMRT provides excellent local-regional control for NPC, with acceptable acute toxicities. Distant metastasis remains the most difficult treatment challenge. More effective systemic chemotherapy should be explored.

Identification of patients with nasopharyngeal carcinoma by serum protein profiling using surface-enhanced laser desorption/ionization time-of-flight mass spectrometry

BACKGROUND

As diagnosis of nasopharyngeal carcinoma at an early disease stage is important, we attempted to distinguish between patients with nasopharyngeal carcinoma and noncancer controls by using serum protein profiles.

METHODS

Surface-enhanced laser desorption/ionization time-of-flight mass spectrometry and CM10 protein chip were used to detect the serum proteomic patterns of 65 patients with nasopharyngeal carcinoma before radiotherapy and 93 noncancer controls. Proteomic spectra of serum samples from 50 nasopharyngeal carcinoma patients and 60 noncancer controls were used as a training set. The validity of the classification tree was then challenged with a blind test set which included another 15 patients with nasopharyngeal carcinoma and 33 noncancer controls. Biomarker Wizard 3.01 and Biomarker Pattern 5.01 were used in combination to analyze the data and to develop diagnostic models.

RESULTS

21 protein peaks were significantly different between nasopharyngeal carcinoma and controls. 4 mass peaks (M4182, M5343, M5913 and M8702 mass/charge ratio) were chosen automatically to construct a classification tree. The classification tree correctly determined 93.8 % (45/48) of the test samples with 93.3 % (14/15) of the nasopharyngeal carcinoma samples and 93.9 % (31/33) of the noncancer samples. Using a combination of serum protein profiles and Epstein-Barr viral capsid antigen immunoglobulin A antibody tests, the diagnostic sensitivity and specificity were increased to 100 and 97 %, respectively.

CONCLUSIONS

Surface-enhanced laser desorption/ionization time-of-flight mass spectrometry could correctly distinguish nasopharyngeal carcinoma from noncancer individuals and showed great potential for the development of a screening test for the detection of 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.

Annexin A1: a new biomarker for predicting nasopharyngeal carcinoma response to radiotherapy

Radiotherapy is the primary treatment for nasopharyngeal carcinoma (NPC), but radioresistance remains a serious obstacle to successful treatment in many cases. Therefore, the biomarkers for predicting NPC response to radiotherapy are very important for targeted therapy and individualized radiotherapy of NPC. Accumulating evidences have shown that Annexin A1 was correlated with NPC radioresistance. First, Annexin A1 is a potential tumor suppressor gene, and can regulate tumor cell proliferation and apoptosis, thus abnormal expression of Annexin A1 in NPC affects apoptosis of tumor cells induced by ionizing radiation and radiotherapeutic efficacy. Second, Annexin A1 is one of the proteins that are involved in p53-mediated radioresponse in NPC, and it might be related to NPC radioresistance. Third, the expression level of Annexin A1 is down-regulated in NPC, and is correlated with metastasis, recurrence and poor prognosis of NPC, thus Annexin A1 downregulation may increase NPC radioresistance, leading to poor prognosis. Last but not the least, Annexin A1 is closely related with tumor chemoresistance, whereas radioresistance is similar to chemoresistance in many aspects, thus Annexin A1 may also be involved in NPC radioresistance. Based on the above mentions, we hypothesize that Annexin A1 is closely correlated with NPC radioresistance and is an important new biomarker for predicting NPC response to radiotherapy.

Radiotherapy concurrently with weekly cisplatin, followed by adjuvant chemotherapy, for N2-3 nasopharyngeal cancer: a multicenter trial of the Forum for Nuclear Cooperation in Asia

The purpose of this study was to evaluate the efficacy and toxicity of radiotherapy concurrently with weekly cisplatin, followed by adjuvant chemotherapy, for the treatment of N2-3 nasopharyngeal cancer (NPC) in Asian countries, especially regions of South and Southeast Asian countries where NPC is endemic. Between 2005 and 2009, 121 patients with NPC (T1-4 N2-3 M0) were registered from Vietnam, Malaysia, Indonesia, Thailand, The Philippines, China and Bangladesh. Patients were treated with 2D radiotherapy concurrently with weekly cisplatin (30 mg/m (2)), followed by adjuvant chemotherapy, consisting of cisplatin (80 mg/m(2) on Day 1) and fluorouracil (800 mg/m(2) on Days 1-5) for 3 cycles. Of the 121 patients, 56 patients (46%) required interruption of RT. The reasons for interruption of RT were acute non-hematological toxicities such as mucositis, pain and dermatitis in 35 patients, hematological toxicities in 11 patients, machine break-down in 3 patients, poor general condition in 2 patients, and others in 8 patients. Of the patients, 93% completed at least 4 cycles of weekly cisplatin during radiotherapy, and 82% completed at least 2 cycles of adjuvant chemotherapy. With a median follow-up time of 46 months for the surviving 77 patients, the 3-year locoregional control, distant metastasis-free survival and overall survival rates were 89%, 74% and 66%, respectively. No treatment-related deaths occurred. Grade 3-4 toxicities of mucositis, nausea/vomiting and leukopenia were observed in 34%, 4% and 4% of the patients, respectively. In conclusion, further improvement in survival and locoregional control is necessary, although our regimen showed acceptable toxicities.

Proposed lymph node staging system using the International Consensus Guidelines for lymph node levels is predictive for nasopharyngeal carcinoma patients from endemic areas treated with intensity modulated radiation therapy

PURPOSE

To propose a lymph node (N) staging system for nasopharyngeal carcinoma (NPC) based on the International Consensus Guidelines for lymph node (LN) levels and MRI-determined nodal variables.

METHODS AND MATERIALS

The MRI scans and medical records of 749 NPC patients receiving intensity modulated radiation therapy with or without chemotherapy were retrospectively reviewed. The prognostic significance of nodal level, laterality, maximal axial diameter, extracapsular spread, necrosis, and Union for International Cancer Control/American Joint Committee on Cancer (UICC/AJCC) size criteria were analyzed.

RESULTS

Nodal level and laterality were the only independent prognostic factors for distant failure and disease failure in multivariate analysis. Compared with unilateral levels Ib, II, III, and/or Va involvement (hazard ratio [HR] 1), retropharyngeal lymph node involvement alone had a similar prognostic value (HR 0.71; 95% confidence interval [CI] 0.43-1.17; P=.17), whereas bilateral levels Ib, II, III, and/or Va involvement (HR 1.65; 95% CI 1.06-2.58; P=.03) and levels IV, Vb, and/or supraclavicular fossa involvement (HR 3.47; 95% CI 1.92-6.29; P<.01) both significantly increased the HR for distant failure. Thus we propose that the N category criteria could be revised as follows: N0, no regional LN metastasis; N1, retropharyngeal lymph node involvement, and/or unilateral levels Ib, II, III, and/or Va involvement; N2, bilateral levels Ib, II, III, and/or Va involvement; N3, levels IV, Vb, and/or supraclavicular fossa involvement. Compared with the 7th edition of the UICC/AJCC criteria, the proposed N staging system provides a more satisfactory distinction between the HRs for regional failure, distant failure, and disease failure in each N category.

CONCLUSIONS

The proposed N staging system defined by the International Consensus Guidelines and laterality is predictive and practical. However, because of no measurements of the maximal nodal diameter on MRI slices, the prognostic significance of LN size needs further evaluation.