TY - JOUR T1 - RAS Mutational Status in Advanced Colorectal Adenocarcinoma Treated With Anti-angiogenics: Preliminary Experience With Liquid Biopsy JF - In Vivo JO - In Vivo SP - 2841 LP - 2844 DO - 10.21873/invivo.12571 VL - 35 IS - 5 AU - BELÉN GARCÍA DE SANTIAGO AU - MIRIAM LÓPEZ-GÓMEZ AU - PEDRO DAVID DELGADO-LÓPEZ AU - ANA JIMÉNEZ GORDO AU - FERNANDO NERIA AU - ISRAEL JOHN THUISSARD-VASALLO AU - CÉSAR GÓMEZ-RAPOSO AU - FRANCISCO ZAMBRANA TEVAR AU - JUAN MORENO-RUBIO AU - ALICIA MARTÍNEZ HERNÁNDEZ AU - IRENE IGLESIAS AU - ENRIQUE CASADO Y1 - 2021/09/01 UR - http://iv.iiarjournals.org/content/35/5/2841.abstract N2 - Aim: To determinate molecular changes in the downstream epidermal growth factor receptor signaling pathway using serial liquid biopsies in patients with metastatic colorectal tumors (mCRC) under anti-angiogenic treatment. Patients and Methods: Determination of RAS mutation in primary tissue samples from colorectal tumors was performed in the 23 patients included in the study at diagnosis using quantitative-polymerase chain reaction. Sequential mutations were studied in circulating tumor (ct) DNA obtained from plasma samples. Results: Twenty-three patients with RAS-mutated primary tumors were included. In the first ctDNA determination, 17 of these patients were found to have wild-type RAS status. Remarkably, three out of these 17 wild-type cases changed to RAS-mutated in subsequent ctDNA assays. Conclusion: Serial liquid biopsies in patients with mCRC might be a useful tool for identifying changes in the RAS mutation status in patients who had undergone previous anti-angiogenic therapy. The understanding of these changes might help to better define the landscape of mCRC and be the path to future randomized studies. ER -