RT Conference Proceedings T1 Concordance of baseline RAS mutational status (ms) between tissue and cell-free DNA (cfDNA) and association with overall response rate (ORR) in first-line (1L) metastatic colorectal cancer (mCRC) patients (pts): PERSEIDA study (cohort 2) (NCT02792478) A1 Valladares-Ayerbes, M. A1 Safont, M. J. A1 Gonzalez-Flores, E. A1 Garcia-Alfonso, P. A1 Aranda Aguilar, E. A1 Lopez-Munoz, A. M. A1 Cirera-Nogueras, L. A1 Falco-Ferrer, E. A1 Rodriguez-Salas, N A1 Aparicio, J. A1 Llanos, M. A1 Castillo-Trujillo, O.A. A1 Pimentel-Caceres, P. A1 Cruz-Hernandez, J. J. A1 Salgado-Fernandez. M., A1 Salud-Salvia, A. A1 Garcia-Carbonero, R. A1 Massuti-Sureda, B. A1 Vicente-Conesa, M. A. A1 Lloansi-Vila, A. K1 Humans K1 Cell-Free Nucleic Acids K1 Standard of Care AB Tumor - tissue biopsy is the standard of care (SOC) to assess RAS & BRAF ms in mCRC pts. However, the analysis of circulating cfDNA has the advantage of evidencing genetic tumor heterogeneity. We explored the occurrence of KRAS, NRAS and BRAF sequence variants (sv) using cfDNA in 1L SOC RAS wt mCRC pts. The concordance of RAS ms between tissue and cfDNA , and the association of cfDNA RAS ms and ORR were also explored. PB Elsevier SN 0923-7534 YR 2021 FD 2021-09-21 LK https://hdl.handle.net/10668/25694 UL https://hdl.handle.net/10668/25694 LA en NO Valladares-Ayerbes, M., Safont, M. J., Gonzalez-Flores, E., Garcia-Alfonso, P., Aranda Aguilar, E., Lopez-Munoz, A. M., et al. Concordance of baseline RAS mutational status (ms) between tissue and cell-free DNA (cfDNA) and association with overall response rate (ORR) in first-line (1L) metastatic colorectal cancer (mCRC) patients (pts): PERSEIDA study (cohort 2) (NCT02792478). Ann. oncol. 2021-09-21; (32); S560 DS RISalud RD Apr 17, 2025