Personalized cancer avatars for patients with thymic malignancies: A pilot study with circulating tumor cell‐derived organoids

BACKGROUND: Systemic therapy is the primary treatment for advanced thymic malignancies. However, there is an urgent need to improve clinical outcome. Personalized treatment based on predictive biomarkers is a potential approach to address this requirement. In this study, we aimed to show the correlation between drug sensitivity tests on CTCs‐derived organoids and clinical response in patients with thymic malignancies. This approach carries the potential to create personalized cancer avatars and improve treatment outcome for patients. METHODS: We previously reported potential treatment outcome prediction with patient‐derived organoids (cancer avatars) in patients with pancreatic ductal adenocarcinoma. To further investigate the feasibility of this approach in advanced thymic malignancies, we conducted a study in which 12 patients were enrolled and 21 liquid biopsies were performed. RESULTS: Cancer avatars were successfully derived in 16 out of 21 samples (success rate 76.2%). We found a sensitivity of 1.0 and specificity of 0.6 for drug sensitivity tests on the cancer avatars, and a two‐tailed Fisher's exact test revealed a significant correlation between drug sensitivity tests and clinical responses (p = 0.0275). CONCLUSION: This study supports the potential of circulating tumor cell‐derived organoids to inform personalized treatment for advanced thymic malignancies. Further validation of this proof of concept finding is ongoing.