Peritoneal cytokines and adhesion formation in endometriosis: an inverse association with vascular endothelial growth factor concentration

Objective: To evaluate inflammatory/angiogenic cytokines-interleukin-1 beta (IL-1 beta), IL-6, IL-8, IL-12, interferon-gamma (IFN-gamma), tumor necrosis factor (TNF), and vascular endothelial growth factor A (VEGF-A)-in the peritoneal fluid of patients with endometriosis in relation to the occurrence and severity of pelvic adhesions and in control women without pelvic pathology. Design: Case-control study. Setting: University research institution and hospital. Patient(s): Sixty-five women with laparoscopically and histopathologically confirmed endometriosis, including 40 women with pelvic adhesions, and 37 control women without pelvic pathology. Intervention(s): Peritoneal fluid aspirated during routine diagnostic laparoscopic examination. Main Outcome Measure(s): Cytokines evaluated in the peritoneal fluid via specific enzyme-linked immunosorbent assays. Result(s): Endometriosis and the revised American Fertility Society score of this disease were associated with statistically significantly increased levels of peritoneal IL-6 and IL-8 whereas the incidence and score of endometriosis-related pelvic adhesions were negatively associated with increased levels of VEGF-A. Notably, the concentration of VEGF-A predicted adhesion development and severity after adjustment for endometriosis severity. The adhesion score also correlated with increased levels of IL-6; however, after adjustment for endometriosis severity, the effect of this cytokine was no longer statistically significant. Conclusion(s): Increased levels of VEGF-A may be associated with a decreased rate of pelvic adhesion formation in the course of endometriosis. (Fertil Steril (R) 2012;97:1380-6. (C) 2012 by American Society for Reproductive Medicine.)