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Background and Objective: The Chinese 2008 staging system for nasopharyngeal carcinoma (NPC) was a common set of recommendations by initial revision of the previous'92 staging system. This study was to verify the Chinese 2008 staging system and to provide evidence for its further revision., Methods: Between January 2003 and December 2004, 924 consecutive patients with newly diagnosed, nondisseminated biopsy-proven NPC, presented at the Department of Radiation Oncology, Cancer Center, Sun Yat-sen University, were entered into our study. All patients received magnetic resonance imaging examination of the neck and nasopharynx before treatment. According to the principle of the staging system, the indices of hazard consistency, hazard discrimination, prognostic value, and distribution were used to evaluate the Chinese 2008 staging system., Results: According to the Chinese 2008 staging system, the distribution of stage group for the whole series was 4.9% for the stage I, 22.6% stage II, 38.0% stage III, and 34.5% stage IVA. As for hazard discrimination, the 4-year local relapse-free survival (LRFS) rates for T1-T4 patients were 95.4%, 93.7%, 90.5% and 79.1%, respectively. Although the separation of LRFS for all subclassifications of T-stage showed reasonable, the differences among the subgroups T1, T2, and T3 were still lack of significant statistically. The 4-year distant metastasis failure-free survival (DMFS) rates for N0-N3 patients were 89.4%, 84.3%, 73.6, and 59.2%, respectively. The 4-year overall survival (OS) rates for stage I-IV patients were 96.7%, 94.1%, 82.6% and 67.1%, respectively. As for hazard consistency, the distinctions between T3 with skull base involvement and T3 with medial pterygoid muscle in the hazard ratios of local failure (1.628 vs. 3.905) and disease failure (1.630 vs. 3.288) were large. Multivariate analyses showed that cervical nodal level, extranodal neoplastic spread, and laterality were independent prognostic factors for OS and DMFS, but maximal axial diameter was not., Conclusion: Using the Chinese 2008 staging system for NPC produces an acceptable distribution of patient numbers. Stage group, T classification, and N classification represent independent prognosis factors for major endpoints. However, our study reveals several deficiencies in the current system yet.

Background & Objective: Since the introduction of the Chinese '92 staging system of nasopharyngeal carcinoma (NPC), the diagnostic technology and therapeutic modality for NPC have been advanced obviously over the past 15 years. This study was to evaluate the staging parameters for NPC in a large cohort based on modern diagnostic and therapeutic modality to provide suggestions for improving the Chinese '92 staging system., Methods: Between Jan. 2003 and Dec. 2004, 924 consecutive patients with newly diagnosed, nondisseminated biopsy-proven NPC, treated at Cancer Center of Sun Yat-sen University, were enrolled. All patients received magnetic resonance imaging (MRI) scan of the neck and nasopharynx before treatment. Induction was applied to evaluate the correlations among different T parameters. Cox regression model was used to investigate the prognostic values of different N parameters. According to the principle of the staging system, the indices of hazard consistency, hazard discrimination, prognostic value, and distribution were used to evaluate the proposed staging system., Results: According to the Chinese '92 T classification, all cases of involvement of the prevertebra muscle, soft palate, pterygopalatine fossa, and orbit were incorporated with erosion of other parameters that belonged to the same or more advanced subgroup; 282 (91.3%) of the 309 cases of carotid sheath involvement were incorporated with erosion of other T3 parameters; 64 (85.3%) of the 75 cases of single anterior or posterior group of cranial nerve involvement were incorporated with erosion of other T4 parameters. The hazard ratios (HR) of local relapse for T3 stage with carotid sheath involvement [HR=1.635, 95% confidence interval (CI): 0.987-2.764] and T2 stage (HR=1.524, 95% CI: 0.910-2.368) were similar. The hazard ratios of local relapse for T3 stage with single site of skull base erosion (HR=3.567, 95% CI: 1.398-11.278), T3 stage excluding single site of skull base erosion (HR=3.891, 95% CI: 1.449-10.449), and T4 stage with involvement of the sphenoid sinus solely (HR=3.613, 95% CI: 1.437-11.854) were similar. The hazard ratios of local relapse for T3 stage with involvement of either anterior or posterior cranial nerves solely (HR=5.849, 95% CI: 2.069-14.500) and T4 stage excluding involvement of the sphenoid sinus (HR=6.618, 95% CI: 2.499-17.525) were similar. Multivariate analysis showed that lymph node metastasis level and laterality were independent predictors for distant metastasis. Therefore, according to the principle of concise, the parameters, including involvement of the prevertebra muslce, soft palate, pterygopalatine fossa and orbit, were deleted. According to the principle of hazard consistency, the involvement of the parapharyngeal spaces, including prestyloid space and poststyloid space, were defined as T2 stage, the involvement of the skull base, including pterygoid process, were defined as T3 stage, the involvement of the sphenoid sinus were defined as T3 stage, and the involvement of the cranial nerves were defined as T4 stage. N staging was optimized by incorporating level and laterality as staging criteria., Conclusion: Based on MRI, the proposed T classification, N classification and clinical staging of NPC are reasonable according to the principle of hazard consistency, hazard discrimination, prognostic value and distribution, and should be recommended for clinical use.

Background & Objective: Three-dimensional conformal and intensity-modulated radiotherapy is the direction of developing radiotherapy for nasopharyngeal carcinoma (NPC). The accuracy of target area outlines is especially important. This study was to explore the clinical diagnostic values of magnetic resonance imaging (MRI), computed tomography (CT), and 18-F-fluorodeoxyglucose (FDG)-positron emission tomography (PET)-CT in detecting retropharyngeal lymph node metastasis of NPC, and to provide references to the plan of radiotherapy., Methods: MRI, enhanced spiral CT, and PET-CT reports of the nasopharynx and whole neck of 87 naive NPC patients, histologically diagnosed and treated in Cancer Center of Sun Yat-sen University between Jan. 2003 and Apr. 2005, were analyzed. The detection rates of retropharyngeal lymph node metastasis were compared among MRI, CT and PET-CT using Chi-square test., Results: Among the 174 parapharyngeal spaces of the 87 patients, the detection rates of retropharyngeal lymph node metastasis by MRI and CT were significantly higher than that by PET-CT (44.8% and 33.9% vs. 24.1%, P < 0.001 and P = 0.002). As compared with CT, MRI played an advantage in detecting retropharyngeal lymph node metastasis of NPC (P = 0.037). The minimal axial diameter of retropharyngeal lymph node was positively correlated to the standard uptake value (SUV) of PET-CT (r = 0.832, P <0.001)., Conclusions: MRI are better than CT and PET-CT in detecting retropharyngeal lymph node metastasis of NPC. The combination of MRI, CT, and PET-CT is useful for delineating targets accurately in 3-dimensional conformal intensity-modulated radiotherapy for NPC.

Background & Objective: The value of magnetic resonance imaging (MRI) in assessing the extension of nasopharyngeal carcinoma (NPC) is better than that of computed tomography (CT). This study was to analyze the influences of MRI on the Chinese '92 staging system and the 6(th) edition International Union Against Cancer/American Joint Committee on Cancer (UICC/AJCC) staging system of NPC., Methods: From Jan. 2003 to Jun. 2004, 250 naive patients with histologically diagnosed NPC, with no metastasis, received both enhanced spiral CT and MRI scans of the nasopharynx and cervix. Clinical stage was classified according to the Chinese '92 staging system and the 6(th) edition UICC/AJCC staging system, respectively, based on both CT/MRI imaging data and clinical information., Results: MRI was better than CT in detecting the invasion of NPC in the extra-nasopharyngeal cavity (the oropharyrnx, nasal cavity, and parapharyngeal spatium), retropharyngeal lymph node, base of skull, paranasal sinuses, intracranial cavernous sinus, infratemporal fossa, and cervical vertebra. There was no statistical difference between CT and MRI in detecting cervical lymph node metastasis. Compared with CT, MRI made changes in 32.0% of T stage (including 26.0% up-staging and 6.0% down-staging), 11.6% of N stage (6.4% up-staging and 5.2% down-staging), and 30.4% of clinical stage (24.0% up-staging and 6.4% down-staging) for the Chinese '92 staging system, while made changes in 39.6% of T stage (36.0% up-staging and 3.6% down-staging), 9.2% of N stage (5.6% up-staging and 3.6% down-staging), and 37.6% of clinical stage (33.6% up-staging and 4.0% down-staging) for the 6(th) edition UICC/AJCC staging system., Conclusions: Compared with CT, MRI has a remarkable advantage in detecting the primary tumor extension of NPC, but has no advantage in detecting cervical lymph node metastasis. It is necessary and feasible to establish a new clinical staging system of NPC based on MRI.

Objective: The prevalence of retropharyngeal lymph node (RLN) metastasis in nasopharyngeal carcinoma (NPC) is high, but its role in '92 Fuzhou staging system for NPC is uncertain. This study was to identify the prognostic value of RLN metastasis in NPC, and to evaluate its role in the staging system., Methods: Clinical data of 749 untreated patients with histologically diagnosed NPC, without metastasis, presented between Jan. 1999 and Dec. 1999 at the Department of Radiation Oncology of Cancer Center of Sun Yat-sen University, were reviewed. All patients received enhanced spiral CT scan on the nasopharynx and whole neck before treatment. Cox regression model was used to investigate the prognostic value of RLN metastasis. According to the principle of the staging system, the indices of hazard consistency, hazard discrimination, and distribution were evaluated to identify the role of RLN metastasis in the staging system for NPC., Results: The occurrence rate of RLN metastasis was 51.5%; the occurrence rates were significantly higher in the patients in advanced T stage, N stage, and clinical stage than in the patients in early stages (57.8% vs. 45.2%, P=0.001; 60.3% vs. 47.6%, P=0.001; 57.9% vs. 38.9%, P<0.001). The 5-year overall survival rate and 5-year distant metastasis-freely survival rate were significantly lower in the patients with RLN metastasis than in the patients without RLN metastasis (58.7% vs. 72.2%, P<0.001; 74.5% vs. 84.9%, P<0.001). In multivariate analysis, RLN metastasis was not a prognostic factor for overall survival, but borderline significant difference was observed for distant metastasis-freely survival (P=0.053). The hazard ratios of death and distant metastasis for N0 stage with RLN metastasis were 0.540 and 0.411, respectively, which was similar to those for N1 stage (0.601 and 0.555, respectively). Classifying RLN metastasis to N1 stage improved the hazard consistency in the N classification, but the distribution was unsatisfactory, and the proportion of N1 stage patients was 50.2%. Classifying RLN metastasis to T2 stage improved the hazard discrimination, with good balances of distribution found in T classification, N classification, and clinical staging., Conclusions: Based on the enhanced CT image, RLN metastasis tends to affect distant metastasis-freely survival of NPC patients. According to the principle of '92 Fuzhou staging system and present patterns of radiotherapy for the primary tumor, classifying RLN metastasis to T2 stage is more reasonable.

Background & Objective: To identify the target volume of radiotherapy is more and more important. This study was designed to explore the regulation for the distribution of metastatic cervical lymph nodes of nasopharyngeal carcinoma (NPC) and to recommend the delineation of clinical target volume of the neck for three-dimensional conformal radiotherapy in NPC., Methods: From Jan. 2003 to Jun. 2004, 512 of cases of NPC, histologically diagnosed, received enhanced transversal CT scan. The cervical node was divided into six levels (I-VI) plus retropharyngeal nodes according to RTOG guidelines proposed in 2003., Results: Of 512 patients, 328 (64.1%) had cervical lymphadenopathy at presentation. Of the 328 neck positive cases, the node involvement was unilateral in 61.3% patient and bilateral in 38.7%. 328 (64.1%) cases showed enlargement of retropharyngeal node, and unilateral 50.9%, bilateral 49.1%. The involvement for levelIto level VI and retropharyngeal area in node-positive cases was 3.0%, 97.9%, 46.0%, 9.5%, 13.7%, 0% and 74.4%. Of the node-positive patient, the incidence of skip metastasis was from 4.6% to 6.5%. 25.3% of the node-positive cases showed involvement, which is beyond CTV for the neck of stage N0 recommended by RTOG., Conclusions: The cervical node involvement of NPC is spread orderly down the neck, and the incidence of skip metastasis is lower. Retropharyneal node was the first echo node to metastases of NPC. The retropharyngeal node, level II, and level III were the most frequently involved area. Level Ia and level VI were never involved. There are few cases with positive nodes beyond CTV for the neck of stage N0 recommended by RTOG. Our data is helpful for the delineation cervical target in the 3-D conformal radiotherapy of NPC.