Epithelial ovarian cancer (EOC) is a deadly gynecologic malignancy, owing to its propensity for intraperitoneal (IP) metastasis. Indeed, almost 75% of women with EOC are diagnosed during the later stages of the disease in which metastasis is already underway. Pathogenesis of EOC is marked by diffuse and widely disseminated metastatic sites within the IP compartment, often with peritoneal ascites. Mouse models of EOC have been developed to facilitate the pre-clinical research of this deadly disease, however the quantification of metastatic tumor burden in these animals has remained challenging due to the broad distribution of lesions in the IP space. Here we describe a combined In Vivo/Post-Mortem method to monitor and measure EOC metastasis in mouse models of obesity. RFP-labeled ovarian cancer cells were injected IP in obese and control cohorts of mice, followed by weekly in vivo imaging until time of sacrifice. Subsequent post-mortem imaging was conducted after surgical exposure of the peritoneal cavity to reveal organs that were then imaged in situ. Ex vivo imaging was performed last on dissected organs from each animal. Imaging signal was enhanced via multispectral imaging methods to remove tissue auto-fluorescence. Semi-quantitative methods to measure tumor burden are demonstrated in their application to the study of metastasis in both obese and control animals. Ultimately these results demonstrated that obesity dramatically increased ovarian cancer metastatic success, and likely contributes to the reduced EOC survival rates noted in clinical reports of obese patients.

Citation Format: W. Matthew Leevy, Yueying Liu, Matthew Metzinger, Kyle Lewellen, M. Sharon Stack. Optical imaging of ovarian cancer metastasis in mouse models of obesity. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 4244.