Introduction Recently, an inflammatory programmed cell death characterized by gasdermin-mediated inflammatory cell death, pyroptosis, was described. Accumulating evidences indicate that pyroptosis can affect the development of tumors, and especially inflammasomes may serve as positive or negative regulators of tumorigenesis. In this study, based on our previous observation of omental CLS formation in advanced OC, we aimed to investigate the role of pyroptosis in inflammatory adipocytes in the OC tumor microenvironment and explore the possible relationship with patient’s prognosis.

Methods Immunohistochemistry: Omental tissue blocks from National Cheng Kung University Hospital were obtained. Informed consents were from each subject before surgery. Statistical analysis: cox proportional hazards model and survival difference were calculated by SPSS as well as GraphPad Prism 8 software to identify significant differences.

Results From 2002 to 2018 , there are 137 serous ovarian cancer patients collected in Cheng Kung University Hospital. The mean age is 56.6 y/o. There are 120 cases in stage III, 17 cases in stage IV. Eighty-six patient (63%) had optimal surgery, while 82 cases (60%) were chemosensitive. For progression free survival analysis through cox proportional hazards model, omental GSDMD (High vs. Low), omental CD68+ CLS (absent vs. present) and omental CD163+ CLS (absent vs. present) showed independent prognostic factors. Patients with high GSDMD expression in omentum tissue carried a poor 5-year survival than those with low GSDMD expression (Hazard ratio 0.56, 95% CI: 0.38–0.82, p=0.003)

Conclusion/Implications High gasdermin D expression in omental adipocytes predicts poor prognosis in advanced stage serous ovarian cancer patients.