Meeting the Needs of Dermatologic Cancer Patients
Dermatologic cancers are the most commonly diagnosed cancer in the U.S. There are 5.5 million new skin cancers diagnosed annually, compared to 1.6 million diagnoses for all other cancers combined. Our focus on skin cancer is based on unmet clinical needs that can be addressed by understanding the biology of individual tumors. Since skin cancer is the most common type of cancer in the United States, we believe there are opportunities to use our experience in developing first-in-class molecular diagnostics to improve decision-making in several underserved skin cancers. Building on our success in melanoma, we have an active research and development program that is focused on addressing the need for more reliable, consistent information to optimize individual patient management and improve care.
Cutaneous Squamous Cell Carcinoma
Cutaneous squamous cell carcinoma (SCC), a non-melanoma skin cancer, is one of the most common cancers with an estimated incidence of more than 1,000,000 cases in the U.S. each year. Approximately 20% of patients have high-risk features based on tumor depth, histology, anatomic location and/or immunosuppression. Most patients have a favorable prognosis, but a subset of patients will develop metastasis and up to 15,000 patients each year die from their disease – more than are estimated to die from cutaneous melanoma.
|Estimated 1 million cases of SCC in the US each year|
|Approximately 20% of patients have high-risk features based on tumor depth, histology, anatomic location and/or immunosuppression|
|Existing staging is poorly predictive, leading to over and under-treatment|
To address this clinical need, Castle Biosciences is developing a gene expression profile test to improve upon current staging systems and identify patients with SCC at high risk for metastasis and death. This would enable more informed clinical decisions regarding adjuvant therapy and other management options.
Significant development progress has been made to date including:
- Promising results from an ongoing multi-center development study of more than 700 SCC specimens accrued from over 40 centers.
- Identification of genes that exhibit significant differential expression between non-recurrent and recurrent cases leading to preliminary gene set and predictive algorithm.
- Preliminary prediction models showing higher sensitivity and positive predictive value that compares favorably to current staging methods.
Based on preliminary validation results, an expanded validation program is now underway.
Suspicious Pigmented Lesions
In the U.S. approximately 2 million biopsies are performed annually to rule out melanoma. These are typically pigmented lesions for which the healthcare provider suspects melanoma. Thankfully, approximately 85% of these biopsies receive a definitive diagnosis by the dermatopathologist using traditional microscopic analyses. However, around 300,000 of the biopsies are difficult to diagnose using traditional histopathology and generally require molecular testing to assist in clarifying the likelihood that this lesion is benign or melanoma.
|Estimated 2 million biopsies per year of pigmented lesions.|
|Approximately 15% (300,000 biopsies) cannot be confidentially confirmed as melanoma or benign lesion through histopathology alone.|
|Under-calling as well as over-calling a melanoma diagnosis has direct implications on treatment plan decisions, unnecessary complications and healthcare costs.|
To address this clinical need, Castle Biosciences is developing a proprietary gene expression profile test designed to be used as an adjunct to histopathology when the distinction between a benign lesion and melanoma is uncertain. Our analysis has identified several gene expression profile algorithms that we believe may be used to confirm whether a specimen is melanoma or a benign lesion.