Perineural invasion in squamous cell carcinomas. Results of a prospective study of 1399 tumors
Between 2005 and 2015, 1399 unselected primary SCCs of 1434 patients were diagnosed. If a patient had multiple tumors, the tumor with the highest risk profile was selected. Histological sections of all tumors with a tumor thickness of ≥6mm and desmoplastic SCC (dSCC) with a tumor thickness of 2.1-5.9 mm were re-examined for PNI. Median follow-up was 36.5 months.