Paraneoplastic Syndrome Associated with the Retroperitoneal Dedifferentiated Liposarcoma: an Atypical Presentation and Review of the Literature.

Retroperitoneal liposarcoma is usually asymptomatic until it is large enough to compress the surrounding organs. Here, we report a rare atypical case of primary retroperitoneal dedifferentiated liposarcoma who presented primarily with the misguiding and challenging paraneoplastic symptoms of high-grade fever and thrombocytosis instead of demonstrating the usual compressive symptoms. Such an extremely rare clinical presentation may mislead the diagnostic and treatment approach towards the search for medical causes, without a hint, that the tumor itself is causing these symptoms. Complete tumor excision usually leads to resolution of these paraneoplastic symptoms.