An autopsy case of metastasizing protuberant dermatofibrosarcoma

An autopsy case of metastatic dermatofibrosarcoma protuberans (DP) together with the results of four sequential biopsies performed during his illness was reported. In this case, the tumor recurred repeatedly for 38 years in spite of intensive treatments. Finally, the tumor metastasized to the bilateral lungs, retroperitoneum and lumbar vertebrae. The direct cause of death was renal stones which may have been related to paraplegia of the lower limbs due to the vertebral metastasis. The metastasis appeared to have started at the time when the tumor showed marked atypism histologically. It was also recognized that there was an obvious difference in atypism between recurrent and metastatic tumors.