Dedifferentiated liposarcomas with divergent myosarcomatous differentiation developed in the internal trunk: a study of 27 cases and comparison to conventional dedifferentiated liposarcomas and leiomyosarcomas.
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.
Binh
Matthieu Bui Nguyen
MB
Department of Pathology, Institut Bergonié and Université Victor Segalen, Bordeaux, France.
Guillou
Louis
L
Hostein
Isabelle
I
Château
Marie Christine
MC
Collin
Francoise
F
Aurias
Alain
A
Binh
Bui Nguyen
BN
Stoeckle
Eberhard
E
Coindre
Jean-Michel
JM
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*
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