Track

Clinical Studies

Abstract

Cutaneous squamous cell carcinoma (cSCC) is the second most common type of skin cancer, with perineural invasion (PNI) found in 2.5 – 5.0% of cSCC. PNI is a sign of metastasis and invasion, and portends a poor prognosis. Although previous genetic studies have explored the relationship between the NOTCH-1 pathway and cSCC with PNI, results have been inconclusive. Here, we investigate if there is a difference in immunohistochemical staining patterns of NOTCH-1 in cSCC with versus without PNI. We conducted a retrospective study, examining 22 cases of cSCC with PNI. Slides were reviewed and stained for NOTCH-1. We found that 86% (19/22) of cSCC with PNI were associated with the loss of NOTCH-1 staining within the tumor. The three tumors with perineural invasion that retained NOTCH-1 staining all showed an infiltrative histologic pattern of growth/invasion. Our findings suggest that the loss of NOTCH-1 staining in a lesion could serve as a valuable marker for PNI in cSCC, aiding clinical teams in identifying cases warranting further investigation. Although NOTCH-1 immunohistochemical staining is not a definitive diagnostic method, its use can alert teams to the possibility of PNI. Given the advancements in modern medicine and the development of molecular therapies targeting these genes, early identification of PNI through immunohistochemical staining could facilitate more targeted treatments with potentially reduced side effects, thereby impacting patient outcomes.