Guardant Health reported strong Q1 2026 revenue growth and raised full-year guidance after oncology testing volumes and minimal residual disease (MRD) demand accelerated. The company posted Q1 revenue of $301.7 million, up 48% year over year, and increased its full-year outlook to $1.30 billion–$1.32 billion. Guardant attributed growth to higher volumes across its Guardant360 liquid and tissue franchises, including a 36% year-over-year increase in oncology testing revenue and more than doubling MRD Reveal volumes. The company is also upgrading Reveal to include whole-transcriptome RNA testing, which management said could expand adoption among non-users. Separately, Guardant said it has submitted data packages to CMS MolDx in multiple breast cancer surveillance and monitoring contexts, aiming for reimbursement-related catalysts.