Purpose:The cutaneous squamous cell carcinoma is the second most common skin malignancy. It is noted that keratoacanthoma is difficult to differentiate from squamous cell carcinoma, clinically or historically. It is still a hypothetical question whether keratoacanthoma is a pseudomalignancy or a form of squamous cell carcinoma.
Methods:We report the case of squamous cell carcinoma around left ala of nose in a 64-year-old female patient. Through an incisional biopsy, the mass was found to be keratoacanthoma in the pathologic report. An excisional biopsy was performed.
Results:Pathologic report notified that it was found well-differentiated squamous cell carcinoma arising in keratoacanthoma with focal involvement of deep resection margin. Wide excision was made with 0.5-1.5cm margin and immediate reconstruction was performed.
Conclusions:The relationship between keratoacanthoma and squamous cell carcinoma has been debated in the treatment. It is still controversial whether to excise it or not. We concluded that kerathoacanthoma must be removed completely.