Trop2-expression in primary vulvar squamous cell carcinoma

Vulvar squamous cell carcinoma (VSCC) is a rare malignant disease but with increasing incidence. Therapeutic options are generally limited to surgery and radio-(chemo)therapy. New strategies for therapy are lacking. Trophoblast cell surface antigen 2 (Trop2) is a new target being used in different tumor entities. The purpose of the current research is to assess the expression of Trop2 in VSCC. We constructed a next generation tissue micro array (ngTMA) including women with primary VSCC treated between 2000 and 2021 at the Department of Gynecology and Obstetrics, Erlangen University Hospital analyzing the expression of Trop2. Further clinicopathologic characteristics were analyzed: tumor stage, regional lymph node-status, venous-, lymphatic- and perineural sheath invasion, depth of invasion, grading, p16/p53 subtype and tumor infiltration lymphocytes. A total of 217 women were included. Trop2 was expressed in 100 % of VSCC. Women were split in two groups, the "low expression" and the "high expression" groups, according to the median of Trop2 (H-score: 279). p16+/p53- is the most common p16/p53 subtype in patients with high Trop2 expression. Trop2 favored a better prognosis in women with VSCC, hence not clinically impactful for the most common p16-/p53+ subtype. The ubiquitous expression of Trop2 makes it an interesting potential target for the Trop2 directed antibody drug conjugate (ADC) sacituzumab govitecan (SG). Clinical trials evaluating the safety and effectiveness of SG in VSCC are needed.