Abstract
Purpose: Dermatofibroma is a lesion several millimeters to several centimeters in size, arising from dermis or subcutaneous tissue, mostly at extremities of a middle aged female. It is a benign fibrous tumor that to our knowledge metastasis have not been reported and may recur only locally. Here we report a rare case of 36-year-old female with dermatofibroma arising from back and metastasized to both lungs. Methods: We performed an en-block elliptical mass excision for skin lesion and metastatectomy for multiple nodules of both lungs. Results: Histologically, the tumors of both lungs and skin lesion showed dilated cystic airspaces which were lined by respiratory epithelium with underlying layers of tumor cells. The tumor cells were composed of plump to spindled fibrohistiocytic cells arranged in storiform growth pattern. There were no cellular pleomorphism, atypical mitosis, and necrosis. These are the specific features of a dermatofibroma and we could examined the histologic findings of skin and lungs identical. Thus, this indicates that dermatofibroma of back was metastasized to both lungs. Conclusion: We report this case to notice that dermatofibroma is a benign tumor but it rarely metastasizes.