Liposarcoma dedifferentiated

Soft tissue sarcomas with a potentially pleomorphic histologic appearance (Fig. 4.28 see Table 4.7) include so-called MFH (undifferentiated pleomorphic sarcoma), pleomorphic rhabdomyosarcoma, pleomorphic or dedifferentiated liposarcoma, dedifferentiated LMS, and pleomorphic MPNST. 

KER, keratin, detected by a mixture of CAMS.2, MAK-6, and AEl /AE3 EMA, epithelial membrane antigen VIM, vimentin DES, desmin MSA, muscle-specific actin SMA, smooth muscle (alpha isoform) actin CALD, h-caldesmon S-1 OOP, S-100 protein LM, laminin UL, Ulex europaeus I lectin binding OCN, osteocalcin PRMS, pleomorphic rhabdomyosarcoma PLPS/DLPS, pleomorphic and dedifferentiated liposarcoma PLMS/DLMS, pleomorphic and dedifferentiated leiomyosarcoma MPNST, pleomorphic malignant peripheral nerve sheath tumor MFH, malignant fibrous histiocytoma DCHOR, dedifferentiated chordoma DCHS, dedifferentiated chondrosarcoma POCS, pleomorphic osteosarcoma. 

S-100 protein in their lipoblastic elements. As mentioned earlier in this discussion, dedifferentiated liposarcomas often show strong nuclear expression of MDM2, usually with CDK4. The high mobility group A2... 

HMGA2) protein is another intranuclear architectural transcription factor that is also overexpressed in dedifferentiated liposarcoma, more often than CDK4. Such tumors are typically nonreactive for epithelial, Schwann-cell related, and myogenic markers. 

As mentioned earlier in this discussion, CDK4 and MDM2 immunostains can be utilized to help confirm the adipocytic nature of some problematic soft tissue tumors (namely, dedifferentiated liposarcoma). However, de Vreeze and colleagues have shown that MLPS and round-cell liposarcoma of the extremities typically lack these determinants immunohistochemically. This reflects the fact that such lesions manifest karyotypic abnormalities that are different from well-differentiated and dedifferentiated liposarcomas. ... 

Coindre JM, Hostein I, Maire G, et al. Inflammatory malignant fibrous histiocytomas and dedifferentiated liposarcomas Histological review, genomic profile, and MDM2 and CDK4 status favor a single entity. J Pathol. 2004 203 822-830. 

Italiano A, Bianchini L, Keslair F, et al. HMGA2 is the partner of MDM2 in well-differentiated and dedifferentiated liposarcomas, whereas CDK4 belongs to a distinct inconsistent amplicon. Int J Cancer. 2008 122 2233-2241. 

Ray-Coquard IL, Blay J, Italiano A et al (2011) Neoadjuvant MDM2 antagonist RG7112 for well-differentiated and dedifferentiated liposarcomas (WD/DD LPS) a pharmacodynamic (PD) biomarker study. Abstract 10007b. 2011 ASCO annual meeting, Chicago, IL... 

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