Development of a nonsurgical diagnostic tool for endometriosis based on the detection of endometrial leukocyte subsets and serum CA-125 levels

OBJECTIVE: To determine whether the proportion of several leukocyte subsets is modulated in the endometrium of patients with endometriosis and, if yes, whether it can be used for diagnostic purposes. DESIGN: Case-control study. SETTING: Eight clinical institutions of the Montreal area. PATIENT(S): Women who underwent laparoscopy or laparotomy between 1997 and 2001, who had regular menstrual cycles and were not under hormone treatment for the previous 3 months were selected. This study included 368 women, 173 with surgically confirmed endometriosis and 195 controls with no surgical evidence of endometriosis. MAIN OUTCOME MEASURE(S): Cytometry analysis was used to measure the proportion of several leukocyte subsets among CD45(+) endometrial cells. RESULT(S): The proportion of CD3(+), CD16(+), CD3(-)HLADR(-), CD3(-)CD45RA(-), CD3(+)CD16(-), CD3(+)CD56(-), CD56(-)CD16(+), and CD16b(+) leukocytes was significantly altered in the endometrium of cases compared with controls. A multiple logistic regression model was adjusted with these endometrial leukocytes, serum CA-125 levels, risk factors, and confounders. The diagnostic performance of this predictive model was defined by a specificity of 95% and a sensitivity of 61%. Furthermore, the positive and negative predictive values were 91% and 75%, respectively. CONCLUSION(S): This predictive model represents a novel diagnostic tool to identify women with a high likelihood of suffering from endometriosis.