Evaluation of serum CCL18 as a potential biomarker for ovarian cancer

BACKGROUND: Early detection and differentiation diagnosis of a pelvic mass (PM) is crucial in improving the prognosis of patients with epithelial ovarian cancer (EOC). C-C motif chemokine ligand 18 (CCL18) was reported as a chemokine-mediated tumor-related inflammation that can be detected in serum and may correlate with cancer patients' prognosis. OBJECTIVE: We performed this study to investigate the relationship between CCL18 levels and clinical characteristics of EOC patients, and to explore their diagnostic and prognostic values. METHODS: CCL18 serum concentrations were detected by ELISA in 187 patients with EOC, 126 patients with benign PMs, and 118 healthy controls. CCL18 serum levels were analyzed in the context of patients' clinicopathological information, and ROC analyses were performed to determine the effect of CCL18 on distinguishing benign and malignant PMs. The ability of CCL18 to serve as an EOC biomarker was compared with CA125. Further survival analyses were carried out to assess the prognostic value of CCL18 in EOC patients. RESULTS: Mean serum CCL18 levels were elevated in benign PM patients and were even higher in EOC patients than in healthy controls; furthermore, high CCL18 expression was associated with worse International Federation of Gynecology and Obstetrics (FIGO) staging and predicted a poorer survival of the patient. When compared with CA125, although the sensitivity and negative predictive values (NPV) of serum CCL18 were lower, its specificity and positive predictive values (PPV) were higher. CONCLUSIONS: Serum CCL18 was elevated in patients with EOC and could serve as a new tumor biomarker, which also predicted a poor survival of the patient.