The significant survival advantage of female sex in nasopharyngeal carcinoma: a propensity-matched analysis.

BACKGROUND: Whether females have better survival than males in nasopharyngeal carcinoma is barely acknowledged and the exact explanations remain unknown. METHODS: Overall, 5929 patients receiving treatment between January 2005 and December 2010 were separately stratified by stage into early and advanced stage groups, and by age into premenopausal (⩽45 years), menopausal (46-54 years) and postmenopausal (⩾55 years) groups. Matched males and females in each group were identified using the propensity score matching method. Differences in disease-free survival (DSS), overall survival (OS), distant metastasis-free survival (DMFS) and locoregional relapse-free survival (LRFS) were estimated by the Kaplan-Meier method and Cox regression model. RESULTS: Overall, 398, 923, 744, 319 and 313 pairs of males and females were matched in early stage, advanced stage, premenopausal, menopausal and postmenopausal group, respectively. Females showed significant advantage over males across all end points in both early and advanced stage groups (P⩽0.042). However, this advantage persisted at premenopausal age (P⩽0.042), declined during menopause (DMFS, P=0.021; DSS, P=0.100; OS, P=0.693; LRFS, P=0.330) and totally disappeared at postmenopausal age (P⩾0.344). CONCLUSIONS: Sex significantly affects NPC survival, with a definite female advantage regardless of tumour stage. Intrinsic biologic traits appear to be the exact explanation according to the declining magnitude of sex effect with age.

Comparison of TNM staging systems for nasopharyngeal carcinoma, and proposal of a new staging system.

BACKGROUND: There are few systematic evaluations regarding the sixth and seventh editions of the UICC/AJCC TNM Staging System (TNM6th, TNM7th) and Chinese 2008 Staging System (TNMc2008) for nasopharyngeal carcinoma (NPC). METHODS: We classified 2333 patients into intensity-modulated radiotherapy (IMRT) cohort (n=941) and conventional radiotherapy (CRT) cohort (n=1392). Tumour staging defined by TNM6th, TNM7th and TNMc2008 was compared based on Akaike information criterion (AIC) and Harrell's concordance index (c-index). RESULTS: For T-classification, TNM6th (AIC=2585.367; c-index=0.6390385) had superior prognostic value to TNM7th (AIC=2593.242; c-index=0.6226889) and TNMc2008 (AIC=2593.998; c-index=0.6237146) in the IMRT cohort, whereas TNMc2008 was superior (AIC=5999.054; c-index=0.623547) in the CRT cohort. For N-classification, TNMc2008 had the highest prognostic value in both cohorts (AIC=2577.726, c-index=0.6297874; AIC=5956.339, c-index=0.6533576). Similar results were obtained when patients were stratified by chemotherapy types, age and gender. Using staging models in the IMRT cohort, we failed to identify better stage migrations than TNM6th T-classification and TNMc2008 N-classification. We therefore proposed to combine these categories; resultantly, stage groups of the proposed staging system showed superior prognostic value over TNM6th, TNM7th and TNMc2008. CONCLUSION: TNM6th T-classification and TNMc2008 N-classification have superior prognostic value in the IMRT era. By combining them with slight modifications, TNM criteria can be unified and its prognostic value be improved.

Prognostic value of ABO blood group in southern Chinese patients with established nasopharyngeal carcinoma.

BACKGROUND: ABO blood group is associated with aetiology of nasopharyngeal carcinoma (NPC); however, the effect of it on survival of patients diagnosed with NPC has not been explored. METHODS: We retrospectively analysed two cohorts of southern Chinese patients with WHO histological type III: intensity-modulated radiotherapy (IMRT) cohort, 924 patients; and conventional radiotherapy (CRT) cohort, 1193 patients. Associations of ABO blood group with survival were estimated using Cox regression. RESULTS: In IMRT cohort, we observed significant associations of blood type A with overall survival (OS) and distant metastasis-free survival (DMFS), compared with type O, after adjusting for prognostic factors. Compared with non-A blood types (B, AB, and O), type A patients had significantly lower OS and DMFS (adjusted hazard ratio (HR)=1.49, 95% CI 1.03-2.17, P=0.036; HR=1.68, 95% CI 1.13-2.51, P=0.011, respectively); similar results were obtained in CRT cohort. Subgroup analyses of the entire population showed that lower OS conferred by blood type A was not significantly modified by age, smoking status, drinking status, immunoglobulin A against Epstein-Barr virus viral capsid antigen (VCA-IgA) titre, or chemotherapy; however, lower OS was not observed in female patients or patients with early clinical stage disease. CONCLUSION: ABO blood group is associated with survival in NPC; patients with blood type A had significantly lower OS and DMFS than patients with non-A blood types.

Prognostic impact of family history in southern Chinese patients with undifferentiated nasopharyngeal carcinoma.

BACKGROUND: Family history of cancer is associated with developing nasopharyngeal carcinoma (NPC); however, the impact of it on survival among established NPC patients remains unknown. METHODS: We retrospectively analysed 1773 southern Chinese patients. Associations between a first-degree family history of NPC and overall survival (OS), locoregional relapse-free survival (LRFS) and distant metastasis-free survival (DMFS) were estimated by Cox regression. RESULTS: Among 1773 patients, 207 (11.7%) reported a first-degree family history of NPC. Compared with patients without a family history, the adjusted hazard ratios among those with it were 0.60 (95% confidence interval (CI), 0.37-0.98; P=0.040) for OS, 0.52 (95% CI, 0.24-1.12; P=0.096) for LRFS and 0.51 (95% CI, 0.27-0.97; P=0.040) for DMFS. There were trends for improving OS, LRFS and DMFS with increasing number of affected relatives (Ptrend: 0.050, 0.114 and 0.044, respectively). But no significant benefits of family history in second- or third-degree relatives were observed. In subgroup analysis, we observed the effects of family history with restriction to male patients and those of advanced stage and treated with conventional radiotherapy and addition of chemotherapy. CONCLUSION: A first-degree family history of NPC is associated with improved survival of patients.

Significant efficacies of neoadjuvant and adjuvant chemotherapy for nasopharyngeal carcinoma by meta-analysis of published literature-based randomized, controlled trials.

BACKGROUND: We carried out this meta-analysis to demonstrate efficacies of neoadjuvant chemotherapy (NACT) and adjuvant chemotherapy (AC) for nasopharyngeal carcinoma (NPC) patients based on randomized, controlled trials (RCTs). PATIENTS AND METHODS: We comprehensively searched electronic databases and manuscripts for RCTs and extracted data from eligible studies for meta-analysis. Overall survival (OS) with hazard ratios (HRs), locoregional recurrence rate (LRR) and distant metastasis rate (DMR) with relative risks (RRs) were concerned using random and/or fixed-effects models. Subgroup and sensitivity analyses were also carried out. RESULTS: Six trials in NACT group (n = 1418) and five in AC group (n = 1187) were eligible. HR of death for NACT was 0.82 [95% confidence interval (CI) 0.69-0.98, P = 0.03], corresponding to an absolute survival gain of 5.13% after 3 years. Significant reduction of DMR (P = 0.0002; RR 0.69, 95% CI 0.56-0.84) was also found from NACT. But no decrease in LRR (P = 0.49; RR 0.90, 95% CI 0.66-1.22) was observed. Patients receiving additional AC had lower LRR (P = 0.03; RR 0.71, 95% CI 0.53-0.96). But no benefit of OS and DMR were seen in AC. CONCLUSIONS: NACT can effectively enhance OS and reduce DMR, not LRR in NPC. And AC only helps to better control locoregional recurrence of NPC.