Association between processed meat and red meat consumption and risk of nasopharyngeal carcinoma: evidence from a meta-analysis

Background: Whether processed meat and red meat consumption could increase the nasopharyngeal carcinoma (NPC) risk have produced inconsistent results. Thus, we conducted a meta-analysis from epidemiological studies to assess the associations between them. Methods: We searched the databases of PubMed and Web of Knowledge up to July 2015. A random-effects model was used to combine study-specific relative risks (RR) and 95% confidence interval (CI). Publication bias was assessed by Egger regression asymmetry test. Results: In total, 11 studies involving 4468 NPC cases were included in this meta-analysis. Ten studies reported processed meat consumption and NPC risk, and the RR of NPC risk was 2.11 (95% CI = 1.21-3.70) (P < 0.001). The association was significant in Asia [summary RR = 2.64, 95% CI = 1.12-6.19], but not in the other populations. Pooled results suggested that red meat consumption had an increased but not significant association for NPC risk. No publication biases were found. Conclusions: Our analysis indicated that higher category of processed meat consumption could increase the risk NPC, especially among Asia population. No association was found between red meat consumption and NPC risk, and the results need to be confirmed.