undifferentiated sarcomas
Undifferentiated sarcomas are primitive mesenchymal tumors that cannot be classified among standardized histopathologic entities. Whether they represent a homogeneous group with common histogenesis and clinical behavior or comprise a variety of tumors able to differentiate along specific maturative lineages is still debated.
Primitive undifferentiated sarcomas occur in the trunk, behave aggressively, and express nestin. (#19647855#)
Spindle cell undifferentiated sarcomas occur in extremities, have a favorable outcome, resemble fibrosarcomas, and have similarly low survivin levels and display CD105-positive vascular spaces, which may represent an early hemangiopericytomatous pattern. (#19647855#)
Types
undifferentiated small round cell sarcomas
undifferentiated large round cell sarcomas
undifferentiated fusiform cell sarcomas
References
Undifferentiated sarcoma: does it exist? A clinicopathologic study of 7 pediatric cases and review of literature. Alaggio R, Bisogno G, Rosato A, Ninfo V, Coffin CM. Hum Pathol. 2009 Nov;40(11):1600-10. PMID: #19647855#
Pawel BR, Hamoudi AB, Asmar L, Newton WA Jr, Ruymann FB, Qualman SJ, Webber BL, Maurer HM. Undifferentiated sarcomas of children: pathology and clinical behavior—an Intergroup Rhabdomyosarcoma study. Med Pediatr Oncol. 1997 Sep;29(3):170-80. PMID: #9212841#