title: Dedifferentiated liposarcomas with divergent myosarcomatous differentiation developed in the internal trunk: a study of 27 cases and comparison to conventional dedifferentiated liposarcomas and leiomyosarcomas.
abstract: Dedifferentiated liposarcoma (DLPS) is one of the most frequent sarcomas of the retroperitoneum and represents most undifferentiated sarcomas of the internal trunk. In about 5% cases, the dedifferentiated component is an heterologous sarcoma such as leiomyosarcoma or rhabdomyosarcoma. We reviewed a series of 65 sarcomas with a myogenic differentiation developed in the internal trunk for which initial diagnoses were leiomyosarcoma (37), rhabdomyosarcoma (6), malignant mesenchymoma (6), and DLPS (16). Immunostainings for MDM2, CDK4, alpha smooth actin, desmin, caldesmon, myogenin, c-kit, and progesterone receptor were performed. In 48 cases, the amplification status of MDM2 and CDK4 could be evaluated with quantitative polymerase chain reaction on paraffin-embedded tissues extracted DNAs. After review of the cases, final diagnoses were leiomyosarcoma (35), rhabdomyosarcomatous (20) or leiomyosarcomatous (7) DLPS, probable DLPS (2), and malignant mesenchymoma (1). DLPS were bigger tumors (median: 18.2 cm) than leiomyosarcomas (median: 12 cm). They had a lower 5-year recurrence-free survival than leiomyosarcomas (45% vs. 71%) but a higher 5-year metastasis-free survival (73% vs. 39%). There was no significant difference in overall survival (57% vs. 34%). Outcome of patients with a DLPS with a myosarcomatous component did not differ from conventional DLPS. In conclusion, most sarcomas with a rhabdomyosarcomatous differentiation occurring in the internal trunk of adults are DLPS. Moreover, DLPS with a myogenic component have a low metastatic potential, similar to conventional DLPS and significantly lower to the metastatic potential of leiomyosarcomas.
authors: Department of Pathology, Institut Bergonié and Université Victor Segalen, Bordeaux, France.
authors: Matthieu Bui Nguyen
authors: MB
authors: Binh
authors: Louis
authors: L
authors: Guillou
authors: Isabelle
authors: I
authors: Hostein
authors: Marie Christine
authors: MC
authors: Château
authors: Francoise
authors: F
authors: Collin
authors: Alain
authors: A
authors: Aurias
authors: Bui Nguyen
authors: BN
authors: Binh
authors: Eberhard
authors: E
authors: Stoeckle
authors: Jean-Michel
authors: JM
authors: Coindre
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000032:analysis; D051358:Cyclin-Dependent Kinase 4 / Q000235:genetics / Q000378:metabolism; D004273:DNA, Neoplasm / Q000032:analysis; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D007890:Leiomyosarcoma / Q000737:chemistry / Q000235:genetics / Q000401:mortality / Q000473:pathology*; D008080:Liposarcoma / Q000737:chemistry / Q000235:genetics / Q000401:mortality / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D021141:Nucleic Acid Amplification Techniques; D051736:Proto-Oncogene Proteins c-mdm2 / Q000235:genetics / Q000378:metabolism; D012186:Retroperitoneal Neoplasms / Q000737:chemistry / Q000235:genetics / Q000401:mortality / Q000473:pathology*; D012208:Rhabdomyosarcoma / Q000737:chemistry / Q000235:genetics / Q000401:mortality / Q000473:pathology*; D012983:Soft Tissue Neoplasms / Q000737:chemistry / Q000235:genetics / Q000401:mortality / Q000473:pathology*
chemical_list: D014408:Biomarkers, Tumor; D004273:DNA, Neoplasm; C497206:MDM2 protein, human; D051736:Proto-Oncogene Proteins c-mdm2; C495900:CDK4 protein, human; D051358:Cyclin-Dependent Kinase 4