IL18 and ovarian cancer: In contrast, statistically significant differences in the concentration of pro-inflammatory interleukins (IL-1α, IL-1β, IL-18, IL-36α, IL-36β, IL-36γ) and an interleukin with antagonistic properties (IL-1Ra) were observed in the peritoneal fluid between G1, G2 and G3 stages of histological differentiation, with the concentration of these interleukins being highest in G3 stage, which may suggest the local involvement of these interleukins in the process of ovarian cancer carcinogenesis.