Castle Biosciences, Inc. (CSTL) is a Healthcare stock trading at $21.12 (as of 2026-06-18), with a market capitalization of $639.36M and a trailing P/E of -49.3. Figures are sourced from first-party U.S. SEC EDGAR filings and market data.
Castle Biosciences, Inc. is a diagnostics company offering prognostic and diagnostic testing services using gene expression profile assays for cancers including invasive cutaneous melanoma, uveal melanoma, and squamous cell carcinoma. Its tests are provided through physicians for use with their patients.