Proposal of a clinical typing system and generation of a prognostic model in patients with nasopharyngeal carcinoma from Southern China.

PURPOSE: To propose a novel clinical typing classification focusing on the distinct progression patterns of nasopharyngeal carcinoma (NPC), to supplement our knowledge of the clinical-biological behavior, to provide useful knowledge for treatment planning, and to contribute to basic research in NPC. METHODS: 632 consecutive patients were retrospectively reviewed and analyzed according to the novel typing system. We considered that NPC can be divided into 5 types as follows: limited (L), ascending (A), descending (D) ascending- descending (mixed) (AD), and distant metastasis types (M). The distribution of these clinical types, their association with Epstein-Barr virus (EBV) serology and prognostic value were explored. RESULTS: 55 (8.70%), 59 (9.34%), 177 (28.01%), 321 (50.79%) and 20 (3.16%) patients were classified as Type L, A, D, AD and M, respectively. EBV (VCA)-IgA titers, EBV early antigen (EA)-IgA serum titers, and capsid antigen lg(EBV DNA) were positively associated with the clinical typing (p<0.05). The 3-year overall survival (OS) rates for Types L, A, D, AD and M were 100, 100, 95.10, 88.20 and 59.30%, respectively (p<0.001). A prognostic model was constructed based on pretreatment lg (EBV DNA) and clinical type, which were independent predictors of OS (multivariate Cox proportional model). The prognostic model stratified patients into 4 risk subgroups. The 3-year OS rates of the low, intermediate, high and extremely high risk groups were 99.5, 90.0, 85.5 and 53.2%, respectively (p<0.001). Compared with the low-risk group, the risk of death was 4.96, 8.75 and 35.9 in the intermediate, high and extremely high risk groups, respectively (p<0.001). The model also predicted OS independently of TNM classification. CONCLUSION: This novel clinical typing system and prognostic model can supplement TNM classification, and may help design novel treatment strategies, evaluate risk stratification and investigate the varied biological characteristics of NPC.

Serologic biomarkers of Epstein-Barr virus correlate with TNM classification according to the seventh edition of the UICC/AJCC staging system for nasopharyngeal carcinoma.

This study aimed to investigate the association between Epstein-Barr virus (EBV)-related biomarkers and TNM classification according to the seventh edition of AJCC/UICC staging system for nasopharyngeal carcinoma. Serum VCA-IgA and EA-IgA titers and plasma EBV-DNA load were quantified at baseline in 779 patients; the rates of positivity and titers/load were compared by TNM classification. The VCA-IgA-positive rate was significantly associated with advanced N classification and stage; the EA-IgA-positive rate with advanced T and N classifications and stage; the EBV-DNA-positive rate with advanced T, N and M classifications and stage. The percentage of triple-positive patients was higher in patients with advanced TNM classification. The VCA-IgA titer and EA-IgA titer correlated positively with T classification, N classification and disease stage (1:117 in Stage I, 1:188.4 in Stage II, 1:231.12 in Stage III, 1:265.91 in Stage IV, and 1:18.34 in Stage I, 1:32.11 in Stage II, 1:34.77 in Stage III, 1:37.65 in Stage IV, respectively). EBV DNA load correlated positively with T, N and M classification and stage [median lg (EBV DNA): 0 (IQ range 0-1.85) in Stage I, 1.32 (0-3.51) in Stage II, 3.33 (0-4.30) in Stage III, 3.83 (2.85-4.71) in Stage IV]. Serum VCA-IgA/EA-IgA titers and plasma EBV DNA correlated strongly with TNM classification according to the seventh edition of the AJCC/UICC; however, plasma EBV DNA load could accurately predict metastatic disease. EBV serological biomarkers may enhance the accuracy of TNM staging and help to avoid excessive imaging examinations in routine evaluation.