‘Now you see it⃛now you don‘t.’ Carmoisine vital dye facilitates complete removal of cutaneous neoplasia by intraoperative visual enhancement

Patients presenting for excision of squamous cell carcinomata, including Bowen's disease, in sun-damaged skin often present with poorly defined, morphoeic or multifocal neoplasms, the extent of which can be difficult to identify intraoperatively. Use of vital staining has been commonly used to aid identification and appropriate excision of squamous lesions of the oral cavity and upper aerodigestive tract but has not been readily adopted for cutaneous lesions. We report a case of a morphoeic squamous cell neoplasm of the web space and fingers to illustrate the merits of vital staining cutaneous squamous neoplasms with the simple dye Carmoisine E122. This assists with intraoperative tumour identification and facilitates adequate oncological resection and appropriately planned reconstruction. By comparison with other methods such as Mohs, it is a simple, cheap, and rapid aid that may be used by surgeons of all grades to improve identification of the extent of the neoplasm, without special equipment.