Lipofibromatosis : Differential Diagnosis
Differential Diagnosis of Lipofibromatosis (continued from the previous image): Lipofibromatosis vs Fibrosarcoma: Cellular variants of lipofibromatosis may be mistaken for congenital/infantile fibrosarcoma. Features favoring fibrosarcoma include: high cellularity, herringbone pattern, increased mitotic activity, necrosis, hemorrhage, cytogenetic changes (gains of chromosomes 8, 11, 17, & 20), and t(12;15)(p13;q25) resulting in ETV6-NTRK3 fusion. Lipofibromatosis vs Dermatofibrosarcoma protuberans (DFSP): Storiform arrangement is more pronounced in DFSP. CD34 expression may be present focally at the periphery in LF but is diffusely positive in DFSP. SMA is variably positive in the spindle cells of LF, whereas DFSP is SMA negative. The image shows S100 positivity in a lipofibromatosis-like neural tumor. Image courtesy of: Scott Kilpatrick, MD; used with permission.