Skin malignancy initially misdiagnosed as a benignepidermal cyst

ABSTRACT

Skin cancer, which often occurs as a result of skin exposure to ultraviolet light radiation, usuallypresents with characteristic abnormal features, such as ulcerative lesions, irregular morphology,bleeding, and excessive growth. Therefore, skin cancer rarely resembles a benign tumor on visualinspection. Nonetheless, squamous cell carcinoma and basal cell carcinoma with nodular or polypoidfeatures can have a similar appearance to that of benign tumors, meaning that they aresometimes misdiagnosed as benign. As benign and malignant tumors have some overlappingfeatures, clinicians sometimes use additional imaging techniques such as ultrasonography to improvethe accuracy of the diagnosis because even a malignant tumor that externally resembles abenign tumor generally has internal morphological features characteristic of malignancy, such asinvasion and irregular borders. However, these imaging tools also have limitations, and punch orexcisional biopsy can be needed if malignancy cannot be completely ruled out. Herein, we reporta case of skin malignancy initially misdiagnosed as a benign epidermal cyst based on external visualinspection and ultrasonography.