Correlations Between Serum IL-6 Levels and Radiation Pneumonitis in Lung Cancer Patients: A Meta-Analysis

• Published in: Journal of clinical laboratory analysis 2016-03, Vol.30 (2), p.145-154
• Main Authors: Fu, Zhan-Zhao, Peng, Yong, Cao, Li-Yan, Chen, Yan-Sheng, Li, Kun, Fu, Bao-Hong
• Format: Article
• Language: English
• Subjects: Adult; Aged; Aged, 80 and over; Computer programs; Confidence intervals; Female; Genetic Heterogeneity; Humans; Interleukin 6; Interleukin-6 - blood; Lung cancer; Lung Neoplasms - blood; Lung Neoplasms - complications; Lung Neoplasms - radiotherapy; Male; Meta-analysis; Middle Aged; Minority & ethnic groups; Odds Ratio; Original; Pneumonitis; Publication Bias; radiation pneumonitis; Radiation Pneumonitis - blood; Radiation Pneumonitis - complications; Radiation therapy; radiotherapy; Reviews; Software; Statistics
• ISSN: 0887-8013; 1098-2825
• DOI: 10.1002/jcla.21828

Objective Diagnostic significance of interleukin 6 (IL‐6) for lung cancer patients with radiation pneumonitis (RP) was examined within various studies, but yielded conflicting results. Thus, this meta‐analysis was performed to demonstrate correlations between serum IL‐6 levels and RP in lung cancer patients. Method Electronic databases updated to March 2014 were searched to find relevant studies. Relevant literatures were searched under the PubMed, Embase, Web of Science, Cochrane Library, CISCOM, CINAHL, Google Scholar, CBM and CNKI databases. STATA statistical software (Version 12.0, Stata Corporation, and College Station, TX) Standardized mean difference (SMD), and its corresponding 95% confidence intervals (CIs) were used for this meta‐analysis. In addition, nine cohort studies met the inclusion criteria and involved a total of 137 RP patients and 295 non‐RP patients. Results The results of combined SMD suggested that serum IL‐6 levels in RP patients was significantly higher than in non‐RP patients before radiotherapy. While, there was a significant difference in serum IL‐6 levels of RP patients between before and after radiotherapy, we observed no difference in serum IL‐6 levels between RP patients and non‐RP patients after radiotherapy. Ethnicity‐stratified analyses indicated that increased serum IL‐6 levels were related to the risk of RP in lung cancer patients among Caucasians, but not detected among Asians (all P > 0.05). Conclusion The main finding of our meta‐analysis reveals that increased serum IL‐6 levels may contribute to the incidence of RP in lung cancer patients, especially among Caucasians.