DecisionDx-SCC Significantly Improves Prediction Accuracy of Metastatic Events after Mohs Surgery in New Study of Patients with High-Risk Cutaneous Squamous Cell Carcinoma Tumors of the Head and Neck

Castle Biosciences, Inc. (Nasdaq: CSTL), a company improving health through innovative tests that guide patient care, today announced that new data supporting the utility of its DecisionDx-SCC test in patients with high-risk cutaneous squamous cell carcinoma (SCC) tumors located on the head and neck (H&N) will be shared at the 56th American College of Mohs Surgery (ACMS) Annual Meeting, being held May 2-5 in Phoenix.

“Mohs surgery is commonly used to remove high-risk SCC tumors located on a patient’s head or neck and is the best method to ensure complete removal of the tumor,” said Sherrif Ibrahim, M.D., Ph.D., lead study author and board-certified Mohs micrographic surgeon and dermatologist at Rochester Dermatologic Surgery in Victor, New York. “In most cases, once a tumor is removed completely, the patient is in the clear. However, aggressive SCC tumors may still return in the same location from which they were removed or worse, spread to other parts of the body, posing a very serious health risk to patients.

“The data being presented at ACMS show the power of DecisionDx-SCC to identify these high-risk patients, enabling more risk-appropriate surveillance or adjuvant treatments to help reduce the patient’s risk of these events occurring.”

Details regarding Castle’s poster at ACMS are included below:

• Title: Addition of the 40-gene expression profile (40-GEP) test in risk assessment improves prognostic accuracy and risk stratification for high-risk cutaneous squamous cell carcinoma (HR-cSCC) of the head and neck successfully treated with Mohs micrographic surgery (MMS)
• Poster Number: Poster 21
• First and Presenting Author: Sherrif Ibrahim, M.D., Ph.D.
• Location: Valley of the Sun Ballroom foyer (2nd floor), Sheraton Phoenix Downtown
• Summary: Despite reported definitive, clear tumor margins, 5-8% of patients with high-risk SCC treated with Mohs surgery will still develop metastasis. This study included 417 patients who received definitive Mohs surgery to remove high-risk SCC tumors of the H&N with reported clear margins. DecisionDx-SCC testing of the tumor tissue before removal significantly increased the prediction accuracy of metastatic events, when used alone and when combined with National Comprehensive Cancer Network (NCCN) guidelines, Brigham and Women’s Hospital (BWH) staging or American Joint Committee on Cancer Staging Manual, 8th Edition (AJCC8) staging, to better guide risk-aligned patient care decisions regarding metastatic surveillance or the use of adjuvant treatments like radiation.

Presenting authors will be available to answer questions regarding their posters on Saturday, May 4, from 12-1 p.m. Mountain Standard Time. Abstracts will also be in ACMS' CME & Abstract Book and available for online viewing via the Planstone abstract site.