Squamous-cell carcinoma arising in a lateral periodontal cyst

A rare case of well-differentiated squamous-cell carcinoma arising in the epithelial lining of a lateral periodontal cyst is reported. Submission of surgically removed tissues for histopathologic evaluation is emphasized. The surgical site has been reconstructed and functions well. Because of early diagnosis and treatment, the patient has no evidence of clinical disease 2 1/2 years postoperatively.