Transvaginal ultrasonography combined with CA-125 plasma levels in the diagnosis of endometrioma

OBJECTIVE: To assess the role of transvaginal ultrasonography combined with CA-125 plasma levels in the diagnosis of endometrioma. DESIGN: Prospective study with pathological confirmation of the diagnosis. SETTING: Department of Obstetrics and Gynecology of the University of Cagliari, Italy. PATIENTS: One hundred one consecutive premenopausal nonpregnant women submitted to laparoscopy or laparotomy, from November 1993 to October 1994, because of the presence of an adnexal mass. INTERVENTIONS: Within 2 days before surgery all patients underwent transvaginal ultrasonography and evaluation of CA-125 plasma levels. The ultrasonographic impression and the CA-125 value were then compared with the histopathological diagnosis. MAIN OUTCOME MEASURE: The overall agreement between the test result and the actual outcome was calculated using the kappa index for the transvaginal ultrasonography used alone and for the combination of transvaginal ultrasonography and CA-125 values, for each chosen cutoff and range. RESULTS: Transvaginal ultrasonography has a strong agreement between test and surgery (kappa value 0.76) whereas the combined use of the two methods is associated with a lower kappa index, ranging from 0.40 to 0.69. CONCLUSION: Transvaginal ultrasonography used alone has a better predictive capacity in differentiating endometrioma from other adnexal masses than combined methods.