Castle Biosciences, Inc. functions as a commercial-stage diagnostics firm, with its primary objective being the provision of both diagnostic and prognostic testing services, specifically targeting various dermatological cancers. Their flagship product, DecisionDx-Melanoma, represents an advanced multi-gene expression profile (GEP) assay engineered to assess the probability of metastasis in patients afflicted with invasive cutaneous melanoma. In addition to their leading solution, the company has created several other specialized, proprietary tests. Among these is DecisionDx-UM, a GEP test tailored to forecast the risk of metastasis for individuals with uveal melanoma, a less common malignancy of the eye. Another key offering is DecisionDx-SCC, a distinctive 40-gene expression profile test that utilizes a patient's unique tumor biology to predict their specific risk of squamous cell carcinoma metastasis, particularly for those presenting with recognized risk factors. Moreover, they offer DecisionDx DiffDx-Melanoma and myPath Melanoma, both proprietary GEP tests employed to assist in the accurate diagnosis of ambiguous pigmented lesions. These specialized testing services are provided by Castle Biosciences to patients predominantly through their healthcare providers. The organization commenced operations in 2007 and maintains its corporate headquarters in Friendswood, Texas.