Rare Aggressive Behavior of MDM2-Amplified Retroperitoneal Dedifferentiated Liposarcoma, with Brain, Lung and Subcutaneous Metastases

Abstract

Dedifferentiated liposarcoma (DDL) is a histologically pleomorphic sarcoma, traditionally defined as well-differentiated liposarcoma with abrupt transition to high grade, non-lipogenic sarcoma. It can occur as part of recurrent well-differentiated liposarcoma, or may arise de novo. DDL most frequently occurs within the retroperitoneum, and while it is prone to local recurrence, it usually has a lower rate of metastasis than other pleomorphic sarcomas. We describe a case of retroperitoneal dedifferentiated liposarcoma in a 63-year-old male, who showed MDM2 amplification with fluorescence in situ hybridization, which displayed unusually aggressive behavior, with brain, lung and subcutaneous soft tissue metastases. As previous reports of metastatic liposarcoma have largely grouped DDL in with other (genetically and clinically distinct) liposarcoma subtypes, we highlight and discuss the rare occurrence of brain metastasis in MDM2-amplified retroperitoneal liposarcoma.

Deceptive Giant Dedifferentiated Liposarcoma of the Esophagus: An Extremely Rare Surgical Case

“…MDM2 is the most common amplified gene of differentiated liposarcoma, which is expressed at almost 100%. 9 Here, the presence of MDM2 amplification confirmed the diagnosis of dedifferentiated liposarcoma. 6 High amplification levels of MDM2 correlate with poor outcome in patients with dedifferentiated liposarcoma.…”

Obvious Reduction of the Tumor Size in Dedifferentiated Liposarcoma in a Lung Metastasis Patient Receiving Individualized Treatment

“…DDLPS accounts for about 18% of liposarcomas and was described by Evans in 1979. Most DDLPS are primary tumors (80–90%), and secondary dedifferentiation can occur in 10% of cases, mostly related to multiple recurrences of WDLPS [ 3 ]. DDLPS mostly affects middle-aged and elderly patients, and there is no significant gender difference.…”

Expanding the differential of cutaneous epithelioid tumors: A case of dedifferentiated liposarcoma with epithelioid features involving the skin, with review of the literature

“…Superficial liposarcomas are uncommon. A comprehensive review of the literature revealed 159 cases in the dermis and/or subcutis, with only 44 cases mentioning dermal involvement . Superficial liposarcomas have been reported in all four liposarcoma subtypes with PLPS being the most common (n = 95) .…”

“…DDL and myxoid are relatively uncommon (19 and 17 cases respectively) (Table shows the DDL cases). Only four of the 159 cases were metastases, including one case of DDL (Table ). All four metastatic cases originated from retroperitoneal primaries, consistent with the view that retroperitoneal tumors present additional surgical difficulties and may be delayed in their diagnosis due to their deep location, which can contribute to more aggressive behavior.…”

“…Liposarcoma represents roughly 15%‐25% of all reported sarcomas and is the most prevalent form of sarcoma in adults . It is categorized into four distinct subtypes: atypical lipomatous tumor/well‐differentiated liposarcoma (WDL), dedifferentiated (DDL), myxoid, and pleomorphic (PLPS) .…”