Use of double-bladed biopsy in distinguishing keratoacanthoma from squamous cell carcinoma—a case report

“The SCC Biopsy Tool” (name provided by current authors) is a double-bladed scalpel handle (manufactured and distributed by Surgidental Instruments, Deer Park, NY, USA) with two No. 11 scalpel blades (Swann-Morton, Sheffield, England) set in parallel, 1.5 mm apart (Figure 1). It provides an alternative to other partial biopsy methods and provides advantages over established techniques of shave and punch biopsy, particularly in differentiating squamous cell carcinoma (SCC) from keratoacanthoma (KA) on the leg and foot. The method of obtaining a full-thickness sample across the total width of a lesion with histologic sectioning in a longitudinal plane enables both architecture and cytology to be assessed accurately; precisely the requirement for distinguishing SCC from KA. The advantage over traditional incisional biopsy with a single blade is precision of parallel edges in a situation where central keratin provides an obstacle to such precision.