Risk of second primary malignancies after nasopharyngeal carcinoma: A population-based cohort study in Taiwan

Background The purpose of this study was to examine the risk of second primary malignancy (SPM) after nasopharyngeal carcinoma (NPC). Methods We compared the incidence of SPM in patients diagnosed with NPC at the end of 2009 using the data extracted from the Taiwan Longitudinal Health Insurance Database between 2001 and 2008 (n = 10,299), with age-matched controls (1:10; n = 102,990). Results We found a 55% increased risk of SPM in patients diagnosed with NPC, compared to the risk of first malignancy in the age-matched controls (incidence rate ratio [IRR] = 1.55; p < .0001). Although the diagnosis of SPM was negatively correlated with the survival of patients with NPC (p = .0011), primary NPC did not display any synergic effect on the survival of patients with SPM, compared to age-matched controls with a newly diagnosed malignancy (p = .8986). Conclusion NPC is associated with an increased risk of developing an SPM. © 2013 Wiley Periodicals, Inc. Head Neck 36: 209–214, 2014