Exhibit 99.1 Castle Biosciences Reports First Quarter 2024 Results Q1 2024 revenue increased 74% over Q1 2023 to $73 million Q1 2024 total test reports increased 40% over Q1 2023 Raising full-year 2024 revenue guidance to $255-265 million from $235-240 million Conference call and webcast today at 4:30 p.m. ET FRIENDSWOOD, Texas - May 2, 2024--Castle Biosciences, Inc. (Nasdaq: CSTL), a company improving health through innovative tests that guide patient care, today announced its financial results for the fir ...