Squamous cell carcinoma arising in the background of an epidermoid cyst: A case report from Syria

Introduction: Malignant transformation of epidermoid cysts is rare, it accounts for 1% of all diagnosed cysts. Transformation into squamous cell carcinoma and basal cell carcinoma can occur. Clinical examination, radiological examination, and pathological confirmation are necessary for diagnosis and the treatment of choice is usually surgical excision. Case Report: A 57-year-old Syrian female patient presented to our hospital with a huge mass on the back. Computed tomography revealed a subcutaneous huge mass 25.0 × 20.0 × 9.0 cm extended from cervical vertebrae level into upper lumbar vertebrae. Surgery with the intent of wide and complete excision was performed but it was difficult to obtain complete excision of tumor because of extension into the deep muscles. The diagnosis was made by histopathologic examination. It was a malignant transformation into squamous cell carcinoma arising from the epidermoid cyst. The patient received radiotherapy after surgery because of incomplete excision of tumor. Conclusion: This case shows an unusual presentation of a huge epidermoid cyst on the back with transformation into malignancy. We aimed to highlight the importance of early diagnosis and treatment of these cysts.