Prognostic significance of parapharyngeal space venous plexus and marrow involvement: potential landmarks of dissemination for stage I-III nasopharyngeal carcinoma

Survival among subgroups of patients with stage II nasopharyngeal carcinoma

To assess survival between subgroups (T1N1, T2N0, and T2N1) of patients with stage II nasopharyngeal carcinoma (NPC). This retrospective cohort study evaluated pathologically confirmed stage II NPC patients from The Surveillance, Epidemiology, and End Results (SEER) database from 2004 to 2016. The included patients were divided into three subgroups: T1N1, T2N0, and T2N1. Overall survival (OS) and cancer-specific survival (CSS) were assessed using the Kaplan-Meier method among the three subgroups. This study investigated 836 patients: 383 (45.8%) patients were in the T1N1 subgroup, 175 (20.9%) patients were in the T2N0 subgroup, and 278 (33.3%) patients were in the T2N1 subgroup. The 5-year OS (75.7%, 68.6%, and 75.7%) and CSS (85.3%, 83.4%, and 84.5%) were similar among the T1N1, T2N0, and T2N1 subgroups. Univariate and multivariate regression analyses revealed that the subgroup (T1N1, T2N0, and T2N1) of stage II NPC was not an independent prognostic factor for OS or CSS. Survival was comparable among subgroups (T1N1, T2N0, and T2N1) of stage II NPC patients. However, patients with T1N1, T2N0, and T2N1 stage disease who receive different treatments might have different prognoses.

MRI of nasopharyngeal carcinoma: parapharyngeal subspace involvement has prognostic value and influences T-staging in the IMRT era

OBJECTIVES

To identify the prognosis of parapharyngeal space involvement (PPSI) based on the number of subspaces involved (pre-styloid space, carotid space (CS), areas outside the CS) and explore its significance for current T-staging in patients with nasopharyngeal carcinoma (NPC).

METHODS

PPSI was retrospectively identified in 1224 patients with non-disseminated NPC at two centers on MRI and separated into four invasion patterns: pattern A (only post-styloid space), pattern B (post-styloid space, CS extension), pattern C (post-styloid space, pre-styloid space extension), and pattern D (all spaces). The Kaplan-Meier analysis and multivariate Cox regression models were used.

RESULTS

PPSI was diagnosed in 63.4% of cases, with patterns A, B, C, and D in 14.3%, 3.8%, 25.3%, and 18.6% of cases, respectively. No prognostic heterogeneity was observed between pattern B and pattern C (p > 0.05). Thus, the degree of PPSI was based on the number of subspaces involved: grade 0 (none), grade 1 (one), grade 2 (two), and grade 3 (three), which could independently predict overall survival (OS) (p < 0.001). T3 patients with grade 0/1 PPSI (slight-T3) had a better prognosis than those with grade 2/3 PPSI (severe-T3) in terms of OS, locoregional-free survival (LRFS), and progression-free survival (PFS) (all p < 0.001), whose hazard ratios were higher and lower than those with T1 and T2, respectively. Combining the T2 and slight-T3 groups as the proposed T2 provided significant differences in OS, LRFS, and PFS between T2 and T3 (all p < 0.05).

CONCLUSIONS

The risk of death increased with the number of parapharyngeal subspaces involved. The degree of PPSI is recommended to optimize T3 heterogeneity.

KEY POINTS

• Parapharyngeal space involvement was proposed to differentiate patient risk groups based on the number of involved subspaces: grade 0 (none), grade 1 (one), grade 2 (two), or grade 3 (three). • The degree of parapharyngeal space involvement was an independent negative prognosticator for OS. • The degree of parapharyngeal space involvement may influence T-staging in patients with nasopharyngeal carcinoma.

Benefit of chemotherapy in stage III nasopharyngeal carcinoma: Analysis of the surveillance, epidemiology, and end results database

OBJECTIVES

Chemoradiotherapy is the standard treatment for locoregionally advanced nasopharyngeal carcinoma (NPC). We aimed to reveal factors associated with chemotherapy use and evaluate chemotherapy's benefit in patients with stage III NPC stratified by lymph node status.

PATIENTS AND METHODS

Overall, 1452 patients with stage III NPC who underwent radiotherapy with (n = 1361) or without (n = 91) chemotherapy were identified in the SEER database. We examined predictors for chemotherapy use using logistic regression analysis. We compared all-cause mortality (ACM) and cancer-specific mortality (CSM) using the Kaplan-Meier method. Cox regression and competing risk analyses were used to evaluate the benefit of chemotherapy. The inverse probability of treatment weighting (IPTW) approach was applied to reduce selection bias and adjust for competing risks. Subgroup analyses and interaction effects were explored.

RESULTS

Factors including age, sex, insured status, tumor grade, and N category were associated with chemotherapy use. Chemotherapy was associated with decreased 5-year ACM (31.4% vs. 48.4%, p < 0.001) and CSM (25.5% vs. 35.8%; p = 0.017) in stage III NPC patients. The IPTW-adjusted hazard ratio for 5-year ACM was 0.57 (95% CI: 0.38-0.86, p = 0.008), whereas IPTW-adjusted sub-hazard ratio for 5-year CSM was 0.62 (95% CI: 0.42-0.93, p = 0.003). A significant interaction effect existed between lymph node status and treatment modality. Chemotherapy offered a significant survival benefit in node-positive stage III NPC. However, no chemotherapy benefit for the node-negative disease was observed.

CONCLUSION

Chemotherapy adds survival benefit in stage III NPC, especially in patients with node-positive disease. The magnitude of chemotherapy benefit in node-negative stage III NPC warrants further investigation.

Staging of T2 and T3 nasopharyngeal carcinoma: Proposed modifications for improving the current AJCC staging system

Objectives

We aimed to reconstitute T2 and T3 stage classification in nasopharyngeal carcinoma (NPC) cases and verify its utility in clinical settings.

Materials and Methods

We enrolled 792 NPC patients. Cox proportional hazards model was used to compare the effect sizes (hazard ratio [HR]) of the cranial structure invasion on survival and select the structures for up‐staging or downstaging T2 and T3 NPC. The samples were reclassified and the survival curves for T2 and T3 stages were analyzed. The proposed new staging system was validated on an external sample (n = 433).

Results

Thirteen cranial structures were examined. American Joint Committee on Cancer (AJCC) T3 stage patients with the invasion of the base of the sphenoid (HR = 2.58, 95% CI = 1.16‐5.77) or base of the pterygoid (HR = 2.00, 95% CI = 0.84‐4.77) had significantly lower hazard ratios than T2 stage patients with the invasion of soft tissues in the bilateral parapharyngeal space (HR = 5.26, 95% CI = 2.02‐13.68) and single/bilateral carotid sheath (HR = 7.78, 95% CI = 3.06‐19.76). T3 stage with the invasion of the above‐mentioned bones was reclassified as T2, and T2 stage with the invasion of the above‐mentioned soft‐tissue structures was reclassified as T3. Survival analysis showed a significant difference between the reclassified T2 and T3 stages (P < 0.001). The results were replicated in the validation samples.

Conclusion

The proposed staging system for defining T2 and T3 stage NPC appears to be superior to the AJCC 8th edition. It could improve prognosis and optimize the treatment selection.

Relationship between pretreatment concentration of plasma Epstein-Barr virus DNA and tumor burden in nasopharyngeal carcinoma: An updated interpretation

Background

Pretreatment plasma Epstein‐Barr virus (EBV) DNA is an important tumor marker and prognostic factor in nasopharyngeal carcinoma (NPC). This study aimed to clarify the relationship between plasma EBV DNA level and tumor burden.

Materials and Methods

Pretreatment tumor burden was measured by radiologically delineated volumes, including nasopharynx tumor volume (GTVnx) and malignant nodes volume (GTVnd); pretreatment level of plasma EBV DNA was quantified by quantitative polymerase chain reaction. The relationship between natural logarithm of EBV DNA (ln‐DNA) and square root of tumor volume (sq‐GTV) was analyzed by Pearson correlation coefficient and partial correlation coefficient. Correlations in subgroups of tumor and nodal stages were also analyzed. A linear regression model was constructed to evaluate the contribution of tumor volumes to plasma EBV DNA. The prognostic effects of EBV DNA independent of tumor burden were evaluated.

Results

Two thousand two hundred and forty nine nonmetastatic NPC patients with detectable plasma EBV DNA were included in correlation analyses. Ln‐DNA showed significant correlation with sq‐GTVnx (r = 0.171) and sq‐GTVnd (r = 0.339) separately. Together, sq‐GTVnx and sq‐GTVnd could only explain 12.9% of the ln‐DNA. Tumor and nodal stages of disease could clearly influence the strength of relationship in subgroup analysis. After excluding confounding volume information, EBV DNA still can predict death and distant metastasis, but not locoregional relapse.

Conclusion

This study suggests that plasma EBV DNA is not only an index of tumor burden, but may also reflect other tumor features, such as accessibility to circulation, angiogenesis, tumor cell kinetics, metabolic activity, and metastatic potential, among others.

A novel scoring model to predict benefit of additional induction chemotherapy to concurrent chemoradiotherapy in stage II-IVa nasopharyngeal carcinoma

OBJECTIVES

Induction chemotherapy (IC) is gaining recognition for the treatment of nasopharyngeal carcinoma (NPC). We aimed to develop a model to predict benefit from additional IC to concurrent chemoradiotherapy (CCRT).

MATERIALS AND METHODS

From an NPC-specific database, 7413 patients with stage II-IVa disease who received CCRT with or without IC were included. Distant metastasis-free survival (DMFS) was the primary outcome and benefit from IC was evaluated by adjusted hazard ratio. Interaction terms between IC and other prognostic factors were identified in multivariate Cox model, and IC benefit score (ICBS) was calculated based on β coefficients from the Cox model.

RESULTS

Nodal category, overall stage, and pre-treatment plasma Epstein-Barr virus DNA (log transformed as continuous variable) interacted with IC and determined ICBS. ICBS could discriminate patients who benefited differently from IC in terms of DMFS well, especially for patients with high and low ICBS. As for patients with medium ICBS, predictive performance of ICBS seemed reduced.

CONCLUSIONS

Based on the ICBS model, we proposed a decision-making process to help in clinical practice. Multi-institutional and prospective studies are warranted to further validate our findings.

Nasopharyngeal carcinoma: Experience and treatment outcome with radical conformal radiotherapy from a tertiary care center in India

BACKGROUND AND AIM

The majority of nasopharyngeal carcinoma (NPC) reports on the outcome and prognostic factors are from endemic high-risk regions. Data on the outcome of Indian patients are sparse. In this study, we retrospectively analyzed the outcome of NPC patients treated radically with conformal radiotherapy (RT). The primary objective was to assess the outcome, and the secondary objectives were to assess treatment-related morbidities and the impact of various prognostic factors on the outcome.

MATERIALS AND METHODS

Sixty-eight patients with biopsy-proven NPC who received radical conformal RT, i.e., three-dimensional conformal RT or intensity-modulated RT (IMRT) during 2004-2013 were analyzed. All patients received conformal RT with or without chemotherapy. Statistical analysis was performed using Statistical Package for the Social Sciences (SPSS, version 20.0) software, IBM, USA. Survival analysis was performed using Kaplan-Meier method. For calculating the hazard ratio of the prognostic factors, univariate and multivariate Cox regression analyses were done. Chi-square test was used to determine the association.

RESULTS

In this study, with a median follow-up of 43 months, the overall survival (OS), disease-free survival, and cause-specific survival were 91, 85.2, and 98.4% at 2 years and 78.3, 72.8, and 88.2% at 3 years, respectively. The locoregional failure was low (3%), and the 5-year cause-specific survival with chemoradiation was excellent (79%), even with 50% of the patients being nonmetastatic Stage IV. Eleven out of 12 failures were distant metastases. The treatment-related late morbidities were acceptable and better with IMRT. Significant prognostic factors affecting the outcome were composite stage of the disease and the interval between diagnosis and treatment initiation.

CONCLUSION

In locally-advanced NPC, excellent local control is possible with modern conformal RT with concurrent chemotherapy. Distant metastases remain a therapeutic challenge despite systemic chemotherapy. Novel systemic therapies are needed in the future for improving the OS of these patients.

Concurrent chemoradiotherapy degrades the quality of life of patients with stage II nasopharyngeal carcinoma as compared to radiotherapy

The purpose of this study was to compare the quality of life (QoL) of stage II nasopharyngeal carcinoma (NPC) patients treated with radiotherapy (RT) versus concurrent chemoradiotherapy (CCRT). In a cross-sectional study, these patients were treated with RT (n = 55) or CCRT (n = 51) between June 2008 and June 2013. For all subjects, disease-free survival was more than 3 years. QoL was assessed using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30 (EORTC QLQ-C30) questions and the Head and Neck 35 (EORTC QLQ-H&N35) questions. RT had better outcomes than CCRT for global QoL, functional scales, symptom scales of fatigue and insomnia, financial problems, and weight gain. Survivors receiving 1 cycle of concurrent chemotherapy had worse QoL outcomes than survivors receiving 2 cycles of concurrent chemotherapy. Patients receiving 3 cycles of concurrent chemotherapy had the best QoL outcomes. Thus, CCRT adversely affects the QoL of patients with stage II NPC as compared to radiotherapy.

Intensity-modulated radiotherapy controls nasopharyngeal carcinoma distant metastasis and improves survival of patients

BACKGROUND

This study evaluated the distant metastatic outcomes in nasopharyngeal carcinoma (NPC) patients treated with intensity-modulated radiotherapy (IMRT) plus chemotherapy.

METHODS

530 Non-metastatic NPC patients were retrospectively collected and reviewed after receiving IMRT with or without chemotherapy between June 2006 and December 2011. Patients were treated with one fraction of IMRT daily for 5 days a week for 69.96-74.09 Gy, while 473 (89.2 %) of patients also received chemotherapy.

RESULTS

Patients were followed up for a median follow-up duration of 49 months (range from 5 to 98 months). After treatment, 91 (17.3 %) patients developed distant metastasis. Distant metastasis after treatment was significantly associated with advanced 2010 Union for International Cancer Control (UICC)/American Joint Committee on Cancer (AJCC) T staging (p = 0.034), N stage (p < 0.001), 2010 UICC/AJCC stage (p < 0.001), and tumor recurrence (p = 0.029). However, chemotherapy failed to reduce cancer distant metastasis in early stage patients, the distant metastasis rate was 17.5 % in stage III and 24.2 % in stage IVA-B diseases, after IMRT and chemotherapy. The multivariate analysis showed that cancer remission duration, treatment modality, and metastatic site (p < 0.001, p = 0.027 and p = 0.022, respectively) were all independent predictors for overall survival of NPC patients after IMRT and chemotherapy.

CONCLUSIONS

This study provided insight into the effects of IMRT plus chemotherapy in the treatment of NPC. Future studies will explore the efficacy of more aggressive systemic therapies for high-risk patients with distant metastasis.

Magnetic Resonance Imaging-Detected Intracranial Extension in the T4 Classification Nasopharyngeal Carcinoma with Intensity-Modulated Radiotherapy

PURPOSE

This study was conducted is to identify the prognostic value and staging categories of magnetic resonance imaging (MRI)-detected intracranial extension in nasopharyngeal carcinoma (NPC) with intensity-modulated radiotherapy (IMRT) to determine whether it is necessary to subclassify the T4 classification NPC.

MATERIALS AND METHODS

A total of 335 nonmetastatic T4 classification NPC patients with MRI treated between March 2004 and June 2011 by radical IMRT were included. The T4 classification patients were subclassified into two grades (T4a, without intracranial extension vs. T4b, with intracranial extension) according to the site of invasion.

RESULTS

The frequency of intracranial extension was 40.9% (137 of 335 patients). Multivariate analysis identified subclassification (T4a vs. T4b) as an independent prognostic factor for local failure-free survival (p=0.049; hazard ratio [HR], 0.498) and overall survival (p=0.004; HR, 0.572); however, it had no effect on regional failure-free survival or distant failure-free survival (p > 0.050).

CONCLUSION

For patients with T4 classification NPC, those with MRI-detected intracranial extension are more likely to experience local failure and death after IMRT than patients without intracranial extension. According to the site of invasion, subclassification of T4 patients as T4a or T4b has prognostic value in NPC.

Prognostic Value of Cavernous Sinus Invasion in Patients with Nasopharyngeal Carcinoma Treated with Intensity-Modulated Radiotherapy

Purpose

To investigate the prognostic value of cavernoussinus invasion (CSI) in patients with nasopharyngeal carcinoma (NPC) treated with intensity-modulated radiotherapy (IMRT).

Patients and Methods

Retrospective review of data from 1,087 patients with biopsy-proven, non-metastatic NPC. All patients were diagnosed using magnetic resonance imaging (MRI) scans and received IMRT as the primary treatment.

Results

The incidence of cavernoussinus invasion in this cohort was 12.1%. In univariate analysis, 5-year overall survival (OS) (70.6% vs. 88.5%, P < 0.001) and distant metastasis-free survival (DMFS) (71.4% vs. 87.7%, P < 0.001), but not locoregional relapse-free survival (LRFS) (93.9% vs. 93.7%, P = 0.341), were significantly different between patients with and without cavernoussinus invasion. In the T4 subgroup, the 5-year OS, DMFS, and LRFS of patients with and without cavernoussinus extension were 70.6% vs. 81.9% (P = 0.011), 71.4% vs. 84.1% (P = 0.011), and 91.2% vs. 89.7% (P = 0.501), respectively. In multivariate analysis, cavernoussinus invasion was an independent prognostic factor for poorer OS (HR = 1.782; P = 0.013) and DMFS (HR = 1.771; P = 0.016), but not LRFS (HR = 0.632; P = 0.294). In patients with lymph node metastasis, the DMFS rates of patients with and without cavernoussinus invasion were significantly different (P < 0.001). Preliminaryanalysis indicated that neoadjuvant chemotherapy led to better DMFS and OS in patients with cavernoussinus invasion than concurrent chemotherapy or radiotherapy alone; however, the differences were not significant.

Conclusions

In the IMRT era, cavernoussinus invasion remains a prognostic factor for poor DMFS and OS in NPC, even in patients with T4 disease.

Concurrent chemoradiotherapy for T3-4 and N0-1 nasopharyngeal cancer: Asian multicenter trial of the Forum for Nuclear Cooperation in Asia

The aim of this study was to evaluate the toxicity and efficacy of radiotherapy concurrent with weekly cisplatin for T3-4 and N0-1 nasopharyngeal cancer. Between 2005 and 2010, 70 patients with nasopharyngeal cancer (T3-4 N0-1 M0, World Health Organization Type 2-3) from Vietnam, Indonesia, Malaysia and Thailand were registered. Patients were treated with 2D radiotherapy concurrent with weekly cisplatin (30 mg/m(2)). Neither adjuvant nor induction chemotherapy was given. Ninety-three percent of the patients completed at least four cycles of weekly cisplatin during radiotherapy. The median total doses for the primary tumor and positive lymph nodes were 70 and 66 Gy, respectively. The median overall treatment time of concurrent chemoradiotherapy was 52 days. No treatment-related deaths occurred. Grade 3-4 acute toxicities of mucositis, nausea/vomiting and leukopenia were observed in 34%, 4% and 4% of patients, respectively. With a median follow-up time of 52 months for the 40 surviving patients, the 3-year local control, locoregional tumor control, distant metastasis-free survival and overall survival rates were 80%, 75%, 74% and 80%, respectively. In conclusion, the current results illustrate that our concurrent chemoradiotherapy regimen was feasible, but disease control remained insufficient. Further research is encouraged in order to improve clinical outcomes.

Omission of Chemotherapy in Early Stage Nasopharyngeal Carcinoma Treated with IMRT: A Paired Cohort Study

The objective of this study was to evaluate the necessity of concurrent chemotherapy in T1-2N1 nasopharyngeal carcinoma (NPC) patients treated with intensity-modulated radiation therapy (IMRT). The retrospective analysis was conducted using the paired comparison method. We matched cases to controls using the greedy matching algorithm with 1:1 control to case ratio. Controls were matched to cases by factors including age, gender, T stage, and duration of RT. The control group included patients received IMRT alone. In another group, concurrent chemotherapy (DDP 40 mg2/m/w) was administrated to each paired patient. From Jan 2009 to Dec 2011, a total of 86 well-balanced T1-2N1 (2002 UICC staging system) NPC patients were retrospectively analyzed. Half of them (43 patients) received radical IMRT alone and another 43 received concurrent chemotherapy with IMRT (CCRT). Median follow-up is 37.4 months (4.8-66.2 months). All patients received a radiation dose of 66 Gy/30Fx. In the CCRT group, all patients received a cumulative dose of ≥ 200 mg/m2. The differences of 3-year overall survival (OS), 3-year progression-free survival (PFS), 3-year relapse-free survival (RFS), and 3-year metastasis-free survival (MFS) between 2 groups were not significant (P > 0.05). The most frequently increased toxicities related to chemotherapy were mild to moderate leukopenia (P = 0.003) and mild anemia (P = 0.008).Omission of weekly cisplatin chemotherapy resulted in comparable survival outcomes to CCRT in IMRT populations. More data from future randomized trials are warranted to further confirm it.

Chemoradiotherapy regimens for locoregionally advanced nasopharyngeal carcinoma: A Bayesian network meta-analysis

BACKGROUND

Concurrent chemoradiotherapy followed by adjuvant chemotherapy (CRT-A) is often the regimen of choice in locoregionally advanced nasopharyngeal carcinoma (NPC). Many alternative regimens have been reported in the literature, however, it is unknown how effective these regimens are compared to each other due to the lack of direct comparisons. Our objective was to perform a network meta-analysis (NMA) to determine the relative survival benefits of these treatments for locoregionally advanced NPC.

METHODS

We performed a systematic review following the Cochrane methodology, using MEDLINE, EMBASE and CENTRAL to identify all randomised controlled trials (RCTs) that compared different chemoradiotherapy regimens for locoregionally advanced NPC. Overall survival (OS) was the primary outcome of interest, and hazard ratios (HRs) were extracted using the Parmar method. Bayesian NMAs with random effects were conducted using WinBUGS.

RESULTS

Twenty-five RCTs (5576 patients) were included in this review. All together, these trials compared seven different regimens: radiotherapy (RT), concurrent chemoradiotherapy (CRT), neoadjuvant followed by CRT (N-CRT), CRT-A, RT-A, N-RT and N-RT-A. All regimens that contained CRT performed significantly better than RT. CRT-A did not improve survival compared to CRT alone (0.98; 95% credible regions: 0.71-1.34). For N-CRT versus CRT, the HR was 1.03 (0.69-1.47). When CRT-A was compared against N-CRT, the resulting HR was 0.96 (0.64-1.48).

CONCLUSIONS

Adjuvant chemotherapy does not appear to improve survival following CRT. The efficacies of CRT, CRT-A and N-CRT all appeared to be similar. Further studies are warranted to determine the value of additional chemotherapy phases in specific patient subgroups.

A Bayesian network meta-analysis comparing concurrent chemoradiotherapy followed by adjuvant chemotherapy, concurrent chemoradiotherapy alone and radiotherapy alone in patients with locoregionally advanced nasopharyngeal carcinoma

BACKGROUND

Given the lack of studies, whether the addition of adjuvant chemotherapy (AC) to concurrent chemoradiotherapy (CCRT) is superior to CCRT alone for locoregionally advanced nasopharyngeal carcinoma (NPC) remains unclear. The main objective of this Bayesian network meta-analysis was to determine the efficacy of CCRT + AC when compared with CCRT alone.

PATIENTS AND METHODS

We systematically searched databases and extracted data from randomized, controlled trials involving NPC patients randomly assigned to receive CCRT + AC, CCRT, or radiotherapy (RT). Overall survival (OS), locoregional recurrence-free survival (LRFS), and distant metastasis-free survival (DMFS) with hazard ratios (HRs) were investigated. A Bayesian network for different outcomes was established to incorporate all evidence. Multiple treatment comparisons based on the network integrated the efficacy of CCRT + AC, CCRT, and RT.

RESULTS

Eight studies involving 2144 patients were analyzed. In the network meta-analysis, CCRT + AC and CCRT were both significantly better than RT alone for all outcomes, except that no significant difference was found between CCRT and RT for LRFS. Though ranking probabilities showed that CCRT + AC was ranked superior to CCRT for OS, LRFS, and DMFS, no significant differences were found between CCRT+AC and CCRT for all outcomes [OS: HR = 0.86, 95% credible interval (CrI) 0.60-1.16; LRFS: HR = 0.72, 95% CrI 0.43-1.15; DMFS: HR = 0.86, 95% CrI 0.62-1.16].

CONCLUSIONS

No significant improvement was found following CCRT + AC compared with CCRT alone. Whether the omission of additional AC can reduce toxic effects without adversely affecting survival in patients with locoregionally advanced NPC should be further explored, in addition to the precise patient status that would benefit from AC following CCRT.

Prognostic significance of the various classifications for parapharyngeal space involvement in nasopharyngeal carcinoma

CONCLUSION

Advanced parapharyngeal space (PPS) involvement showed stronger prognostic value than PPS involvement. The classification of PPS involvement proposed by Min or Sham was the most appropriate classification for parapharyngeal extension in nasopharyngeal carcinoma (NPC). The degree of tumor extension into the PPS should be considered in future TNM staging revisions.

OBJECTIVES

This study was conducted to evaluate the prognostic significance of the various classifications for PPS involvement in patients with NPC.

METHODS

From January to July 2000, a total of 176 patients with pathologically diagnosed NPC were prospectively enrolled in this study. The extent of PPS involvement was examined by contrast-enhanced computed tomography (CT) scan and graded according to the four previously reported classifications (Min, Sham, Xiao, and Heng).

RESULTS

The incidence of PPS involvement was 81.8%. The 5-year overall survival (OS), progression-free survival (PFS), distant metastasis-free survival (DMFS), and local relapse-free survival rates (LRFS) of the patients with and without PPS involvement were 68.1% and 90.2% (p = 0.010), 66.1% and 87.2% (p = 0.013), 76.7% and 93.6% (p = 0.032), and 84.9% and 93.1% (p = 0.220), respectively. Multivariate analysis showed that PPS involvement (yes vs no) was not an independent prognostic factor. However, graded PPS involvement was an independent factor affecting the prognosis of NPC. When the four classifications were included in a Cox model, it was shown that PPS involvement based on Min's classification was an independent factor for OS (p = 0.001). PPS involvement based on Sham's classification was an independent factor for PFS (p = 0.010) and DMFS (p = 0.009).

Treatment outcomes for different subgroups of nasopharyngeal carcinoma patients treated with intensity-modulated radiation therapy

Although many studies have investigated intensity-modulated radiation therapy (IMRT) for nasopharyngeal carcinoma (NPC), sample sizes in the reported studies are usually small and different in outcomes in different T and N subgroups are seldom analyzed. Herein, we evaluated the outcomes of NPC patients treated with IMRT and further explored treatment strategy to improve such outcome. We collected clinical data of 865 NPC patients treated with IMRT alone or in combination with chemotherapy, and classified all cases into the following prognostic categories according to different TNM stages: early stage group (T1–2N0–1M0), advanced local disease group (T3–4N0–1M0), advanced nodal disease group (T1–2N2–3M0), and advanced locoregional disease group (T3–4N2–3M0). The 5-year overall survival (OS), local relapse-free survival (LRFS), and distant metastases-free survival (DMFS) were 83.0%, 90.4%, and 84.0% respectively. The early disease group had the lowest treatment failure rate, with a 5-year OS of 95.6%. The advanced local disease group and advanced nodal disease group had similar failure pattern and treatment outcomes as well as similar hazard ratios for death (4.230 and 4.625, respectively). The advanced locoregional disease group had the highest incidence of relapse and death, with a 5-year DMFS and OS of 62.3% and 62.2%, respectively, and a hazard ratio for death of 10.402. Comparing with IMRT alone, IMRT in combination with chemotherapy provided no significant benefit to locoregionally advanced NPC. Our results suggest that the decision of treatment strategy for NPC patients should consider combinations of T and N stages, and that IMRT alone for early stage NPC patients can produce satisfactory results. However, for advanced local, nodal, and locoregional disease groups, a combination of chemotherapy and radiotherapy is recommended.

Role of chemotherapy in stage IIb nasopharyngeal carcinoma

The efficacy of neoadjuvant chemotherapy and adjuvant chemotherapy on stage IIb nasopharyngeal carcinoma (NPC) remains unclear. Conventional two-dimensional radiotherapy combined with concurrent chemotherapy can improve the overall survival, progression-free survival, recurrence-free survival, and distant metastasis-free survival of patients with stage IIb NPC. Intensity-modulated radiotherapy without concurrent chemotherapy also provides good outcomes for patients with stage IIb NPC. This article summarizes the features of stage IIb NPC and reviews the role of chemotherapy in this subgroup of NPC.

Role of chemotherapy in nasopharyngeal carcinoma

Nasopharyngeal carcinoma (NPC) is a unique malignant head and neck cancer with clinical, demographic, and geographic features distinct from other head and neck epithelial malignancies. Non-keratinizing, poorly differentiated, and undifferentiated WHO types 2 and 3 is the most common subtypes of NPC. NPC is also characterized by its relatively high sensitivity to radiation, so that in the last decades radiotherapy (RT) has been the cornerstone of treatment. However, in the majority of cases NPC is discovered at locally advanced stage. The results are disappointing when RT alone is offered. The 5-year survival rates have been reported to be about 34-52%. The poor prognosis for advanced NPC led to increasing interests in exploring the use of chemotherapy (CT). NPC has been considered to be not only radiosensitive but also chemo-sensitive and has shown high response rate to various chemotherapeutic agents. Certainly, the treatment strategies for NPC will continue to change and evolve as a better understanding is gained of the molecular and immune mechanisms that drive this disease. We reviewed the current literature focusing on the role of CT and new-targeted agents.

Prognostic value of subclassification using MRI in the t4 classification nasopharyngeal carcinoma intensity-modulated radiotherapy treatment

PURPOSE

To subclassify patients with the T4 classification nasopharyngeal carcinoma (NPC), according to the seventh edition of the American Joint Committee on Cancer staging system, using magnetic resonance imaging (MRI), and to evaluate the prognostic value of subclassification after intensity-modulated radiotherapy (IMRT).

METHODS AND MATERIALS

A total of 140 patients who underwent MRI and were subsequently histologically diagnosed with nondisseminated classification T4 NPC received IMRT as their primary treatment and were included in this retrospective study. T4 patients were subclassified into two grades: T4a was defined as a primary nasopharyngeal tumor with involvement of the masticator space only; and T4b was defined as involvement of the intracranial region, cranial nerves, and/or orbit.

RESULTS

The 5-year overall survival (OS) rate and distant metastasis-free survival (DMFS) rate for T4a patients (82.5% and 87.0%, respectively), were significantly higher than for T4b patients (62.6% and 66.8%; p = 0.033 and p = 0.036, respectively). The T4a/b subclassification was an independent prognostic factor for OS (hazard ratio = 2.331, p = 0.032) and DMFS (hazard ratio = 2.602, p = 0.034), and had no significant effect on local relapse-free survival.

CONCLUSIONS

Subclassification of T4 patients, as T4a or T4b, using MRI according to the site of invasion, has prognostic value for the outcomes of IMRT treatment in NPC.

Concurrent chemoradiotherapy vs radiotherapy alone in stage II nasopharyngeal carcinoma: phase III randomized trial

BACKGROUND

Concurrent chemoradiotherapy (CCRT) has been shown to improve outcomes for stage III-IV nasopharyngeal carcinoma (NPC) patients compared with radiotherapy (RT) alone, but the effectiveness of the combined therapy for stage II NPC patients is unknown.

METHODS

Patients with Chinese 1992 stage II NPC were randomly assigned to receive either RT alone (n = 114) or CCRT (n = 116). The CCRT patients were given concurrent cisplatin (30 mg/m(2) on day 1) weekly during RT. The primary endpoint was overall survival (OS). Secondary endpoints were progression-free survival (PFS), distant metastasis-free survival, and locoregional relapse-free survival. All patients were analyzed by the intent-to-treat principle. The Cox proportional hazards model was used to calculate hazard ratios (HRs) with 95% confidence intervals (CIs) and in multivariable analyses to test the independent statistical significance of treatment intervention. Toxic effects and the response to treatment were analyzed using the χ(2) test. All statistical tests were two-sided.

RESULTS

With a median follow-up of 60 months, adding chemotherapy statistically significantly improved the 5-year OS rate (94.5% vs 85.8%; HR of death = 0.30, 95% CI = 0.12 to 0.76; P = .007), PFS (87.9% vs 77.8%; HR of progression = 0.45, 95% CI = 0.23 to 0.88; P = .017), and distant metastasis-free survival (94.8% vs 83.9%; HR of distant relapse = 0.27, 95% CI = 0.10 to 0.74; P = .007); however, there was no statistically significant difference in the 5-year locoregional relapse-free survival rate (93.0% vs 91.1%; HR of locoregional relapse = 0.61, 95% CI = 0.25 to 1.51; P = .29). Multivariable analysis showed that the number of chemotherapy cycles was the only independent factor that was associated with OS, PFS, and distant control in stage II NPC. The CCRT arm experienced statistically significantly more acute toxic effects (P = .001), although the rate of late toxic effects did not increase statistically significantly.

CONCLUSION

Concurrent chemotherapy and radiotherapy is associated with a considerable survival benefit for patients with stage II NPC.

Increased risk of ischemic stroke in young nasopharyngeal carcinoma patients

PURPOSE

Radiation/chemoradiotherapy-induced carotid stenosis and cerebrovascular events in patients with nasopharyngeal carcinoma (NPC) can cause severe disability and even death. This study aimed to estimate the risk of ischemic stroke in this patient population over more than 10 years of follow-up.

METHODS AND MATERIALS

The study cohorts consisted of all patients hospitalized with a principal diagnosis of NPC (n=1094), whereas patients hospitalized for an appendectomy during 1997 and 1998 (n=4376) acted as the control group and surrogate for the general population. Cox proportional hazard model was performed as a means of comparing the stroke-free survival rate between the two cohorts after adjusting for possible confounding and risk factors.

RESULTS

Of the 292 patients with ischemic strokes, 62 (5.7%) were from the NPC cohort and 230 (5.3%) were from the control group. NPC patients ages 35-54 had a 1.66 times (95% CI, 1.16-2.86; p=0.009) higher risk of ischemic stroke after adjusting for patient characteristics, comorbidities, geographic region, urbanization level of residence, and socioeconomic status. There was no statistical difference in ischemic stroke risk between the NPC patients and appendectomy patients ages 55-64 years (hazard ratio=0.87; 95% CI, 0.56-1.33; p=0.524) after adjusting for other factors.

CONCLUSIONS

Young NPC patients carry a higher risk for ischemic stroke than the general population. Besides regular examinations of carotid duplex, different irradiation strategies or using new technique of radiotherapy, such as intensity modulated radiation therapy or volumetric modulated arc therapy, should be considered in young NPC patients.

Randomized trial of radiotherapy plus concurrent-adjuvant chemotherapy vs radiotherapy alone for regionally advanced nasopharyngeal carcinoma

BACKGROUND

Current practice of adding concurrent-adjuvant chemotherapy to radiotherapy (CRT) for treating advanced nasopharyngeal carcinoma is based on the Intergroup-0099 Study published in 1998. However, the outcome for the radiotherapy-alone (RT) group in that trial was substantially poorer than those in other trials, and there were no data on late toxicities. Verification of the long-term therapeutic index of this regimen is needed.

METHODS

Patients with nonkeratinizing nasopharyngeal carcinoma staged T1-4N2-3M0 were randomly assigned to RT (176 patients) or to CRT (172 patients) using cisplatin (100 mg/m(2)) every 3 weeks for three cycles in concurrence with radiotherapy, followed by cisplatin (80 mg/m(2)) plus fluorouracil (1000 mg per m(2) per day for 4 days) every 4 weeks for three cycles. Primary endpoints included overall failure-free rate (FFR) (the time to first failure at any site) and progression-free survival. Secondary endpoints included overall survival, locoregional FFR, distant FFR, and acute and late toxicity rates. All statistical tests were two-sided.

RESULTS

The two treatment groups were well balanced in all patient characteristics, tumor factors, and radiotherapy parameters. Adding chemotherapy statistically significantly improved the 5-year FFR (CRT vs RT: 67% vs 55%; P = .014) and 5-year progression-free survival (CRT vs RT: 62% vs 53%; P = .035). Cumulative incidence of acute toxicity increased with chemotherapy by 30% (CRT vs RT: 83% vs 53%; P < .001), but the 5-year late toxicity rate did not increase statistically significantly (CRT vs RT: 30% vs 24%; P = .30). Deaths because of disease progression were reduced statistically significantly by 14% (CRT vs RT: 38% vs 24%; P = .008), but 5-year overall survival was similar (CRT vs RT: 68% vs 64%; P = .22; hazard ratio of CRT = 0.81, 95% confidence interval = 0.58 to 1.13) because deaths due to toxicity or incidental causes increased by 7% (CRT vs RT: 1.7% vs 0, and 8.1% vs 3.4%, respectively; P = .015).

CONCLUSIONS

Adding concurrent-adjuvant chemotherapy statistically significantly reduced failure and cancer-specific deaths when compared with radiotherapy alone. Although there was no statistically significant increase in major late toxicity, increase in noncancer deaths narrowed the resultant gain in overall survival.

Magnetic resonance imaging staging of nasopharyngeal carcinoma in the head and neck

Magnetic resonance imaging (MRI) is the modality of choice for staging nasopharyngeal carcinoma in the head and neck. This article will review the patterns of primary and nodal spread on MRI with reference to the latest 7th edition of the International Union Against Cancer/American Joint Committee on Cancer staging system.

Treatment approaches to nasopharyngeal carcinoma: a review

Early-stage nasopharyngeal carcinoma (T1-2a;N0;M0) represents a small proportion of nasopharyngeal tumors. Radiotherapy alone is the current treatment approach for this tumor and the emerging role of new radiotherapy techniques will hopefully further improve the treatment outcome for these patients. The vast majority of patients with nasopharyngeal carcinoma is diagnosed with locally advanced disease. Concomitant chemoradiotherapy is now acknowledged as being a standard treatment option, even though it induces a considerable incidence of acute mucosal and hematologic toxicity. The issue of adding adjuvant chemotherapy is somewhat more controversial. Similarly, the role of neoadjuvant chemotherapy before concomitant chemoradiotherapy is a matter of interest. In patients with recurrent/metastatic nasopharyngeal carcinoma the prognosis is generally grim, as platinum-based chemotherapy results in a 50-70% response rate and in a median survival time of 11 months. Several trials have been performed on this subset of patients with both cytotoxic and biologic agents, but the results have not been particularly encouraging thus far. Epstein-Barr virus is associated with the vast majority of nasopharyngeal carcinoma. Concentrations of plasma Epstein-Barr virus DNA have been associated with treatment outcome in the clinic. Immunotherapy is generally well tolerated and can sometimes elicit significant immune response, which possibly induces clinical benefit in some patients.

Concurrent chemoradiotherapy with adjuvant chemotherapy for high-risk nasopharyngeal carcinoma

OBJECTIVES

To evaluate the impact of invasion of the prevertebral or parapharyngeal spaces and large tumor volume on treatment outcomes in patients with nasopharyngeal carcinoma (NPC).

METHODS

A total of 105 patients with newly diagnosed NPC were enrolled in this study. TNM stage and presence of invasion of the prevertebral or parapharyngeal spaces were recorded. All patients received a total dose of 70-75 Gy.

RESULTS

After controlling for age, sex, and chemotherapy status, invasion of the prevertebral or parapharyngeal spaces and large primary tumor volume produced a significantly increased hazard ratio for distant metastasis and recurrence. We defined patients with two or more such prognostic factors as high-risk patients, in whom the 3-year metastasis-free survival rate, with and without adjuvant chemotherapy, was 100% and 69.6%, respectively (P=0.02). Their 3-year recurrence-free survival rate, with and without adjuvant chemotherapy, was 93.3% and 70.2% (P=0.09). This benefit was not observed in low-risk NPC patients.

CONCLUSION

NPC patients with any two or more of the factors, involvement of the prevertebral space, large primary tumor volume, or advanced parapharyngeal space invasion, had more recurrence and poor survival rates and benefited from concurrent chemoradiotherapy followed by adjuvant chemotherapy.

The prognostic influence of prevertebral space involvement in nasopharyngeal carcinoma

OBJECTIVES

The purpose of this study was to evaluate the effect of prevetebral space involvement on treatment outcomes in patients with nasopharyngeal carcinoma (NPC) who were treated with radiotherapy/concurrent chemoradiotherpy or concurrent chemoradiotherpy with adjuvant chemotherapy.

DESIGN

A retrospective review of case notes from the Kaohsiung Veterans General Hospital archives was performed.

SETTING

A medical centre in Taiwan.

PARTICIPANTS

There were 145 newly diagnosed cases of NPC. Thirty-nine patients were excluded because of the presence of distant metastasis at the time of presentation, loss of follow-up and incomplete image information.

MAIN OUTCOME MEASURES

Pearson's chi-square tests were used to analyse correlation between tumour invasion and prevetebral space involvement during univariate analysis and logistic regression was applied during multivariate analysis. Kaplan-Meier survival curves were constructed. Multivariate analysis was performed to examine the impact of various prognostic factors. Pearson's chi-square and Fisher's exact test were also used to evaluate the correlation between failure patterns and treatment modality.

RESULTS

A total of 106 patients with newly diagnosed NPC were enrolled in this study. Forty-three patients (41%) in this series were found to have prevertebral space involvement. Patients with prevertebral space involvement conferred a poor overall survival rate and metastasis-free survival rate compared with those without prevertebral space invasion (P = 0.04 and 0.02 respectively). Multivariate analysis showed that prevertebral space invasion was associated with an increased risk for distant metastasis [hazard ratio (HR) 14, 95% confidence interval (CI) 1.0-17.4; P = 0.03)] and overall survival (HR 7, 95% CI 1.1-135; P = 0.04). In patients with prevertebral space involvement, their metastasis-free survival rate, with and without adjuvant chemotherapy, was 100% and 72.7% (P = 0.047). This phenomenon was not observed in NPC patients without prevertebral space invasion.

CONCLUSIONS

The present data revealed that prevertebral space involvement has a close relationship with survival rates and recurrence rates of patients with NPC. Nasopharyngeal carcinoma patients with prevertebral space involvement have more recurrence and poorer survival rates and should be the group to benefit from concurrent chemoradiotherapy followed by adjuvant chemotherapy. Inclusion of prevertebral space involvement may be needed to predict prognosis of NPC and help us to identify the high-risk group.

Treatment outcomes after radiotherapy alone for patients with early-stage nasopharyngeal carcinoma

PURPOSE

To analyze the treatment outcomes of patients with early-stage nasopharyngeal carcinoma after radiotherapy (RT) alone and discuss the effects of different T and N stages on the prognosis.

METHODS AND MATERIALS

The clinical data from 362 early-stage (T1-T2N0-N1M0, 1992 Fuzhou, China staging system) nasopharyngeal carcinoma patients who had undergone RT alone between January 1999 and December 2001 and were hospitalized in the Cancer Center of Sun Yat-Sen University were collected and reviewed.

RESULTS

The median follow-up was 70 months. The 5-year overall survival rate for the whole group was 85%. The 5-year overall survival rate of those with T1N0, T2N0, and T1N1 was 96.6%, 91.3%, and 85.8%, respectively, with no statistically significant difference detected among the three groups (p > .05). However, the 5-year overall survival rate of 73.1% for those with Stage T2N1 was significantly different from that of the former three groups. The 5-year local recurrence-free survival and 5-year regional recurrence-free survival rates among the four groups was not significantly different (p < .05). The 5-year distant metastasis-free survival rate of those with Stage T1N0, T2N0, and T1N1 was 94.9%, 97.5%, and 95.6%, respectively, without any significant differences (p > .05); however, the 81.2% rate for those with Stage T2N1 was significantly different (p < .05).

CONCLUSION

RT alone for Stage T1N0, T2N0, and T1N1 yielded satisfactory results. The outcome for those with T2N1 was obviously poorer than that for the other three groups. The main reason for treatment failure in this group was distant metastasis. Patients who have a high risk of distant metastasis in the T2N1 group may need combined treatment instead of RT alone.

Primary tumor volume of nasopharyngeal carcinoma: significance for recurrence and survival

BACKGROUND

Primary tumor volume (PTV) is known to be a significant prognostic factor in malignant tumor. There have been several studies of nasopharyngeal carcinoma (NPC) relating tumor volume to treatment outcome. Our study was designed to evaluate the effect of PTV on treatment outcomes in NPC treated with radiotherapy (RT)/concurrent chemoradiotherapy (CCRT) or CCRT with adjuvant chemotherapy.

METHODS

We retrospectively reviewed 100 cases with newly diagnosed NPC who were treated with RT/CCRT or CCRT with adjuvant chemotherapy from 2002 to 2006. Magnetic resonance imaging-derived PTV was calculated using the summation-of-area technique. Kaplan-Meier plots and the log-rank test were used to estimate tumor recurrence (locoregional, distant, or both) and overall survival. Cox proportional hazards regression analysis was used to assess the prognostic impact of PTV.

RESULTS

The median PTV was 12.94 mL. PTV remained an independent prognostic factor for distant metastasis (hazard ratio [HR], 1.04; p=0.03), for any relapse (HR, 1.04; p=0.02), and for overall survival (HR, 1.09; p<0.001) in multivariate analysis. In the large tumor volume group (PTV>15 mL), patients' metastasis-free survival rates, with and without adjuvant chemotherapy, were 100% and 68.3%, respectively (p=0.002). Their 3-year recurrence-free survival rates, with and without adjuvant chemotherapy, were 94.1% and 69.6%, respectively (p=0.006). In the small tumor volume group (PTV <or= 15 mL), this phenomenon was not observed.

CONCLUSION

PTV had a close relationship with survival rates and recurrence rates in patients with NPC. The large tumor volume group (PTV>15 mL) was associated with more recurrence and poor survival rate, and it was suggested that these high-risk patients should benefit from CCRT followed by adjuvant chemotherapy.

Systemic approach to improving treatment outcome in nasopharyngeal carcinoma: current and future directions

Systemic therapy is an integral part of the management of non-keratinizing nasopharyngeal carcinoma (NPC). The purposes of this review are to provide the latest results and future directions of clinical and translational research for this disease, and to illustrate how some of these new therapies have improved the treatment outcome for patients with NPC. Particular attention will be paid to the clinical application of chemotherapy in the adjunctive treatment of locoregionally advanced NPC, novel targeted drugs, Epstein-Barr virus-targeted vaccine therapies, and the use of plasma Epstein-Barr virus DNA as a biomarker for selecting patients for adjunctive therapies.

Prognostic influence of parapharyngeal extension in nasopharyngeal carcinoma

CONCLUSIONS

Advanced parapharyngeal tumor involvement in nasopharyngeal carcinoma (NPC) had significant predictive value associated with poorer treatment outcome. Further subclassification of parapharyngeal invasion may be considered in the TNM staging system.

OBJECTIVES

We conducted a retrospective study to elucidate the effect of parapharyngeal extension on treatment outcomes in patients with NPC who were treated with radiotherapy or concurrent chemoradiotherapy (CCRT).

PATIENTS AND METHODS

A total of 99 patients with newly diagnosed NPC were enrolled in this study. The parapharyngeal space invasion examined by CT scan was identified and graded according to Sham and Choy's classification. Potentially significant parameters were analyzed by both univariate and multivariate methods using SPSS software.

RESULTS

The overall survival, recurrence-free survival, locoregional control survival and distant metastasis-free survival rates were affected by the presence of parapharyngeal space involvement (p<0.0001, p<0.0001, p<0.0001, p=0.002, respectively). In multivariate analysis accounting for all previously known prognostic factors, parapharyngeal invasion was associated with increased risk for any recurrence, locoregional recurrence, distant metastasis, and overall survival. After adjusting with TNM classification, parapharyngeal invasion was still an independent prognostic factor in NPC.

Primary tumor volume of nasopharyngeal carcinoma: significance for survival

OBJECTIVES

To elucidate the effect of primary tumor volume (PTV) on treatment outcomes in patients with nasopharyngeal carcinoma (NPC) who were treated with radiotherapy or concurrent chemoradiotherapy. The TNM staging system developed by American Joint Committee of Cancer (AJCC) is universally used and accepted but its prediction of prognosis in NPC receives a lot of challenge. Primary tumor volume had been reported to have close relationship with prognosis of head and neck cancer. We may predict prognosis of NPC with PTV.

METHODS

From 1999 to 2006, 91 patients with newly diagnosed NPC who were treated with radiotherapy or CCRT were enrolled in the study. Computed tomography-derived or magnetic resonance-derived primary tumor volume was calculated. The correlation between AJCC disease stage, primary tumor volume and disease-specific survival were analyzed. Multivariate analyses using the Cox proportional hazard model was performed.

RESULTS

The median primary tumor volume for the whole series was 11.39 ml (range 1.25-166.58 ml). The median primary tumor volume was 2.69 ml in T1 disease, 10.14 ml in T2 disease, 15.41 ml in T3 disease, and 26.69 ml in T4 disease. Hazard ratio increased with tumor volume, ranging from 5.91 (95% confidence interval (95% CI) 1.13-26.43) for tumor volumes between 20 ml and 40 ml, and 15.72 (95% CI, 3.82-61.05) for tumor volumes >40 ml. With both tumor volume and T classification in the same Cox regression model, only tumor volume remained statistically significant in the prognosis of NPC.

CONCLUSION

Primary tumor volume has closer relationship with survival rates of patients with NPC. Calculation of primary tumor volume may be further considered to improve the current staging system.

A prognostic scoring system for locoregional control in nasopharyngeal carcinoma following conformal radiotherapy

PURPOSE

This study established a prognostic scoring system for nasopharyngeal carcinoma (NPC), which estimates the probability of locoregional (LR) control following definitive conformal radiotherapy.

METHODS AND MATERIALS

Patients with nondisseminated NPC at initial presentation (n = 630) were enrolled in this study. All patients had magnetic resonance imaging of the head and neck and were treated with conformal radiotherapy. Among them, 93% had concurrent chemotherapy, and 76% had postradiation chemotherapy. The extent of the primary tumor, age at diagnosis, primary tumor size, tumor and nodal classification, histology, and serum lactate dehydrogenase (LDH) level before treatment were included in the analysis for building a prognostic scoring system. The end point for this study was LR control.

RESULTS

The prognostic score was defined as the number of adverse prognostic factors present at diagnosis. Four factors had similarly independent prognostic effects (hazard ratio, 2.0-2.6): age >40 years, histologic WHO type I-II, serum LDH level > or =410 U/L, and involvement of two or more sites of the following anatomic structures, i.e., sphenoid floor, clivus marrow, clivus cortex, prevertebral muscles, and petrous bone. The score predicted the 5-year probability of LR control as follows: 0 (15% of the patients), 100%; 1 (42% of the patients), 93%; 2 (29% of the patients), 83%; 3 or higher (13% of the patients), 71%.

CONCLUSION

This scoring system is useful in the decision-making for individual patients and the design of clinical trials to improve LR control for advanced-stage NPC.