title: Cyclooxygenase-2 expression is positively associated with lymph node metastasis in nasopharyngeal carcinoma.
abstract: BACKGROUND
  Accumulating evidence has demonstrated that cyclooxygenase-2 (COX-2) is involved in head and neck cancers, especially in nasopharyngeal carcinoma (NPC). However, the association between COX-2 expression and lymph node metastasis in NPC remains uncertain. This systematic review and meta-analysis meta-analysis investigated the relationship between COX-2 expression and lymph node metastasis and other signs of disease progression in NPC.
  
  
  METHODS
  Previously published studies assessing COX-2 expression and lymph node metastasis in NPC were identified in four English databases and three Chinese ones (Pubmed, Embase, Cochrane Database of Systematic Reviews, Web of Science, China National Knowledge Infrastructure, Wanfang, Vip Journal Integration Platform) up to November 2016. Quality of all eligible studies was assessed using the Newcastle-Ottawa Quality Assessment Scale (NOS). Pooled odds ratios (OR) and their 95% confidence intervals (95%CI) were calculated with fixed-effects or random-effects model to evaluate the effects of COX-2 expression on lymph node metastasis.
  
  
  RESULTS
  A total of 27 studies with 1797 NPC patients met the inclusion criteria. The expression of COX-2 was significantly higher in patients with nasopharyngeal carcinoma than those without the carcinoma, with a combined OR of 21.17 (95%CI = 15.02-29.85, I2 = 35.1%, Pheterogeneity = 0.070). A statistically significant association between COX-2 expression and lymph node metastasis in NPC patients, with an OR of 4.44 (95%CI = 3.46-5.70, I2 = 38.3%, Pheterogeneity = 0.024), and with other indicators of disease progression. Subgroup analyses based on COX-2 assay and staging criteria of TNM showed no significant heterogeneity.
  
  
  CONCLUSIONS
  The results suggest that expression of COX-2 is associated with lymph node metastasis and disease progression in NPC, indicating a potential role in evaluation of prognosis and in treatment decisions. COX-2 inhibitors have potential in the treatment of NPC that should be further investigated.
authors.affiliation: Department of Clinical Laboratory, Zhongnan Hospital of Wuhan University, Wuhan, Hubei, China.
authors.forename: Gui
authors.initials: G
authors.lastname: Yang
authors.affiliation: Department of Clinical Laboratory & Center for gene diagnosis, Zhongnan Hospital of Wuhan University, Wuhan, Hubei1, China.
authors.forename: Qiaoling
authors.initials: Q
authors.lastname: Deng
authors.affiliation: Department of Clinical Laboratory & Center for gene diagnosis, Zhongnan Hospital of Wuhan University, Wuhan, Hubei1, China.|Department of Pathology, Zhongnan Hospital of Wuhan University, Wuhan, Hubei, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Fan
authors.affiliation: Department of Clinical Laboratory & Center for gene diagnosis, Zhongnan Hospital of Wuhan University, Wuhan, Hubei1, China.
authors.forename: Zheng
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: Department of Clinical Laboratory & Center for gene diagnosis, Zhongnan Hospital of Wuhan University, Wuhan, Hubei1, China.
authors.forename: Peipei
authors.initials: P
authors.lastname: Xu
authors.affiliation: Department of Clinical Laboratory & Center for gene diagnosis, Zhongnan Hospital of Wuhan University, Wuhan, Hubei1, China.
authors.forename: Shihui
authors.initials: S
authors.lastname: Tang
authors.affiliation: Department of Clinical Laboratory & Center for gene diagnosis, Zhongnan Hospital of Wuhan University, Wuhan, Hubei1, China.
authors.forename: Ping
authors.initials: P
authors.lastname: Wang
authors.affiliation: Department of Clinical Laboratory & Center for gene diagnosis, Zhongnan Hospital of Wuhan University, Wuhan, Hubei1, China.
authors.forename: Jun'e
authors.initials: J
authors.lastname: Wang
authors.affiliation: Department of Clinical Laboratory, Zhongnan Hospital of Wuhan University, Wuhan, Hubei, China.|Department of Clinical Laboratory & Center for gene diagnosis, Zhongnan Hospital of Wuhan University, Wuhan, Hubei1, China.
authors.forename: Mingxia
authors.identifier: http://orcid.org/0000-0002-0529-0030
authors.initials: M
authors.lastname: Yu
mesh_terms: D002277:Carcinoma / Q000473:pathology*; D051546:Cyclooxygenase 2 / Q000378:metabolism*; D006801:Humans; D008207:Lymphatic Metastasis / Q000473:pathology*; D000077274:Nasopharyngeal Carcinoma; D009303:Nasopharyngeal Neoplasms / Q000473:pathology*
chemical_list: D051546:Cyclooxygenase 2