Are selected cell adhesion molecules useful as urinary biomarkers for diagnosing endometriosis?
Prospective, longitudinal study (the Endometriosis Marker Austria) in patients who underwent laparoscopic surgery for benign gynaecological pathologies. A total of 149 patients not receiving hormonal treatment for at least 3 months prior to recruitment were included and preoperative urine protein levels of soluble vascular adhesion molecule-1 (sVCAM-1), soluble intracellular adhesion molecule-1 (sICAM-1), E-selectin and P-selectin were measured using a magnetic bead-based multiplex assay, normalized to creatinine levels of each sample. Levels were correlated with endometriosis status, menstrual cycle phase, body mass index, cigarette smoking and severity and entity of the lesions.
Urine levels of sVCAM-1, sICAM-1, E-selectin and P-selectin did not differ between women with (n = 84) and without (n = 65) endometriosis and among subgroups. Accordingly, receiver operating characteristic analysis to examine the value of using sVCAM-1, sICAM-1, E-selectin and P-selectin levels and sVCAM/sICAM ratio to diagnose endometriosis were not significant. Whether the serum sVCAM-1 levels correlated with the urine levels of the protein in the same women was also investigated, which revealed no significant correlations for sVCAM or sICAM.
Although a previous study had suggested that serum sVCAM is a promising biomarker for diagnosing endometriosis, no significant differences were found in urine levels of sVCAM-1, sICAM-1, E-selectin and P-selectin between women with and without endometriosis. Other markers should be studied in an effort to establish a truly non-invasive urinary test for diagnosing endometriosis.