Abstract
Subungual tumors are rare in general. Of all tumors, subungual squamous cell carcinoma (SSCC) is the most frequent one. Protean clinical presentations and the lack of awareness of the disease are responsible for an incorrect or delayed diagnosis and subsequent delayed treatment. We have reported here four patients with SSCC who were previously wrongly diagnosed with a benign process and treated unsuccessfully for years. We would like to highlight the need of a biopsy in chronic or recurrent nail lesions that fail to respond to a previous conservative treatment in order to rule out SSCC.