(O13) 3D Organoid-Based Drug Sensitivity Analysis for Personalized Chemotherapy in Canine Sarcoma

Abstract: Background – In advanced, high-grade, recurrent, or metastatic sarcomas, chemotherapy is used; however, its effectiveness remains limited. Recently, in human medicine, patient-derived organoids have gained attention as a promising tool for predicting anticancer drug susceptibility, highlighting the potential of organoid-based platforms in personalized cancer treatment. Hypothesis/Objectives – This study aims to develop an organoid-based platform to visually quantify patient-derived organoid responses to chemotherapy, enabling personalized treatment strategies for canine sarcoma. Animals - 10 dogs diagnosed with sarcoma at Korea Animal Medical Center between June 2024 and January 2025 Methods – Canine organoids were generated from tumor tissues through surgical excision confirmed as sarcoma by histopathology. Organoids were treated with chemotherapeutic and targeted drugs for 5 days, and cell viability was assessed using microscopy and a luminol-based assay for comparing drug sensitivities including doxorubicin, toceranib, cyclophosphamide, vincristine, epirubicin, and sorafenib. Results – A total of ten cases were identified, including soft tissue sarcoma (n=5), hemangiosarcoma (n=3), osteosarcoma (n=1), and stromal sarcoma (n=1). Among the tested chemotherapeutic agents, doxorubicin (n=6) exhibited the highest response rate, followed by toceranib (n=3) and mitoxantrone (n=1). The most effective drug varied among individual patients, regardless of tumor type, suggesting that treatment response may be highly patient-specific. Conclusions and Clinical Importance – The evaluation was conducted using a 3D organoid model in canine sarcoma patients. Based on the observed ex vivo responses, this approach could be considered as a tool for applying personalized chemotherapy in vivo. However, further research is needed to validate its clinical utility.