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 (P-trend: 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.