Survival and mutational differences based on ESR1 and ESR2 expression in non-small cell lung cancer (NSCLC). (ASCO 2024)
In EGFR-Mt, a significant difference in survival since treatment (SST) with osimertinib was seen for ESR1-L/ESR2-H (40 m, N = 13), ESR1-H/ESR2-L (36 m, N = 62), ESR1-H/ESR2-H (34 m, N = 161) and ESR1-L/ESR2-L (30 m, N = 138, p = .03). In KRAS G12C-Mt, a significant difference in SST was seen with sotorasib; ESR1-H/ESR2-H had the longest SST (median not reached, N = 17), followed by ESR1-H/ESR2-L (17 m, N = 17), ESR1-L/ESR2-L (13 m, N = 34) and ESR1-L/ESR2-H (1 m, N = 1, p = .002)...ESR1-H had a higher percentage of females, AD, and EGFR/KRAS-mt v ESR1-L while ESR2-H had no sex difference, more SCC, and fewer EGFR/KRAS-mt v ESR2-L. ESR1-H/ESR2-H tumors had the highest MPAS and longest OS and there were SST differences with EGFR and KRAS G12C inhibition. ESR1&2 may play key roles in activating the MAPK pathway and future trials could consider targeted therapy combined with ER inhibition based on ESR1&2 expression.