Guardant Health reported Q1 2026 revenue growth of 48% year over year, lifting its full-year guidance after strong performance in oncology and screening. The company posted $301.7 million in Q1 revenue, beating analysts, and raised 2026 revenue guidance to $1.30 billion–$1.32 billion at the midpoint. Management attributed the results to growth in minimal residual disease (MRD) testing and increased volume across its Guardant360 offerings. Guardant also noted a whole-transcriptome RNA upgrade for Guardant360 Tissue, with executives calling it a volume catalyst for converting non-users. For reimbursement-focused readers, Guardant said it has submitted data packages to CMS’s MolDx program across breast cancer surveillance, immunotherapy monitoring, and chemotherapy monitoring, framing each submission as a potential reimbursement catalyst.