Characterizing the endometrial fluid cytokine profile in women with endometriosis

Purpose To compare growth factor and cytokine profiles in the endometrial secretions of patients with and without endometriosis to determine whether a particular protein profile is predictive of the disease. Methods Patients undergoing laparoscopic gynecologic surgery for benign indications were recruited for this prospective cohort study. Prior to surgery, endometrial fluid was aspirated and multiplex immunoassay was used to quantify 7 cytokines and growth factors. During surgery, each patient was staged according to the ASRM staging system for endometriosis. Cytokines and growth factors were evaluated using the Mann-Whitney and Kruskal-Wallis tests. Combinations of cytokines were evaluated using logistic regression analysis, and ROC curves were generated to evaluate the predictive capacity of the assay. Results Endometrial secretions were analyzed from 60 patients. Nineteen had stage 3-4 endometriosis, 19 had stage 1-2 disease, and 22 had no endometriosis. There were no significant differences between controls and stage 1-2 endometriosis; however, levels of IL-1 alpha and IL-6 were significantly increased in women with moderate-to-severe disease. A combination of IL-1 alpha, IL-1 beta, and IL-6 in endometrial secretions predicts stage 3-4 endometriosis with an AUC of 0.78. A threshold value of 118 pg/mL yields a sensitivity of 75% and specificity of 70%. Conclusion Aspiration of endometrial fluid is a safe and effective approach for evaluating the endometrial profile of women with endometriosis. Women with moderate-to-severe endometriosis demonstrate a distinct cytokine profile compared to controls. A combination of IL-1 alpha, IL-1 beta, and IL-6 in the endometrial secretions is predictive of stage 3-4 endometriosis, but is not predictive of minimal-to-mild disease.