Abstract
INTRODUCTION: Dedifferentiated liposarcoma is rare and tends to present with discrete tumors in the retroperitoneum, limbs and trunk. Majority of cases arise de-novo as primary tumors, while a minority occur as recurrences of well-differentiated liposarcomas. There has been no previous report of dedifferentiated liposarcoma presenting as disseminated intraperitoneal sarcomatosis. PRESENTATION OF CASE: This report describes a young Asian female with disseminated intraperitoneal sarcomatosis arising from de-novo dedifferentiated liposarcoma, and discusses the diagnostic challenges faced in this highly unusual disease presentation. Initial biopsy was unconclusive, and considerations included sclerosing mesenteritis or an inflammatory myofibroblastic tumor. Fluorescence in situ hybridization was subsequently performed and showed amplification of the MDM2 gene. A diagnosis of dedifferentiated liposarcoma was then made. DISCUSSION: This was an extremely unusual presentation of advanced dedifferentiated liposarcoma that was eventually diagnosed using fluorescence in situ hybridization. Prognosis is poor and the only viable treatment options was palliative chemotherapy. CONCLUSION: The diagnosis of dedifferentiated liposarcoma should be considered early and surgery carried out when still feasible.