Evaluation of an IDH1/2 Mutation FastTrack Assay for Patients with Cholangiocarcinoma

Background: Cholangiocarcinoma, a malignancy originating from the bile ducts, poses significant treatment challenges due to its typically late diagnosis and limited therapeutic options. However, recent advances in molecular genetics enable more personalized treatment approaches. A notable breakthrough in this context is the identification of isocitrate dehydrogenase (IDH) mutations, particularly IDH1 and IDH2, which occur in a subset of cholangiocarcinoma patients. Those with IDH1/2 mutations may benefit from targeted therapies. For instance, Ivosidenib, an IDH1 inhibitor, has shown efficacy in clinical trials, offering a new therapeutic option for patients with IDH1-mutant cholangiocarcinoma. Developing and implementing standardized protocols for testing and reporting mutation status are crucial for consistency and accuracy in clinical practice. Both the Idylla (TM) IDH1-2 Mutation Assay Kit as a FastTrack method and Next-Generation Sequencing (NGS) panels play critical roles in molecular characterization of cholangiocarcinoma. Methods: Under this aspect, a set of cholangiocarcinomas was tested using the Idylla (TM) platform regarding the respective recommended guidelines and standards of DIN EN ISO:17020 and DIN EN ISO:15198. Results: Overall, 25 clinically diagnosed intrahepatic cholangiocarcinomas or Adeno-CUPs were analyzed. IDH1/2 mutations were identified in 68% (17/25) of cases using both methods, with high concordance between NGS and Idylla (TM) results. Discrepancies were observed in two samples, where Idylla (TM) detected no mutations, but NGS reported IDH1 and IDH2 mutations, respectively. Conclusions: IdyllaTM offers a rapid, user-friendly, and specific method for detecting IDH1/2 mutations, ideal for immediate clinical needs. NGS, while more time-consuming and costly, provides comprehensive genetic profiles valuable for personalized medicine and research. The choice between these methods should be guided by the clinical context, resource availability, and individual patient needs. For routine diagnostics, we recommend an algorithmic approach starting with the FastTrack method followed by NGS for wildtype cases.