title: Correlation of histological grade of dedifferentiation with clinical outcome in 55 patients with dedifferentiated liposarcomas.
abstract: In this study the histologic grade of dedifferentiated liposarcomas was correlated with outcome in surgically resected specimens in 55 patients over a 19-year period at the University of Pittsburgh Medical Center. The tumors were located in the retroperitoneum (N=35); the extremities and thigh (N=16), and the remainder involved the spermatic cord and head and neck. Most tumors were large (mean=21 cm.) Follow-up was available in all 55 patients (median=36 months). Forty-one tumors classified as high-grade dedifferentiated liposarcoma (HG-DDLPS) had mitotically active pleomorphic and spindle cells and foci of necrosis. They included tumors with foci of smooth muscle differentiation (N=12), osteosarcoma (N=4), and myxoid areas (N=9). Fourteen tumors classified as low-grade dedifferentiated liposarcoma (LG-DDLPS) displayed a predominantly bland, monomorphic, spindle cell population with few mitoses and scant necrosis. The Kaplan-Meier method and log-rank test were used for statistical analysis. All tumors had unequivocal foci of well-differentiated liposarcoma (WDLPS). Fluorescence in situ hybridization (FISH) detected amplification of MDM2 in 29 cases. Twenty of 41 patients (49%) with HG-DDLPS died of tumor, and two patients died with LG-DDLPS (14%). The overall survival of patients with LG-DDLPS was significantly longer (P=.02). The median survival was 113 months for the LG-DDLPS and 48 months for the HG-DDLPS. Metastases (N=4) occurred only in the high-grade tumors and were independent of the type of heterologous differentiation. Patients with HG-DDLPS were at a greater risk of earlier death. Distinction between the two groups is important for patient selection for possible adjuvant therapy.
authors.affiliation: Department of Pathology, Presbyterian Shadyside Hospitals, University of Pittsburgh Medical Center, Pittsburgh, PA 15232.
authors.forename: Kossivi
authors.initials: K
authors.lastname: Dantey
authors.affiliation: Department of Pathology, Presbyterian Shadyside Hospitals, University of Pittsburgh Medical Center, Pittsburgh, PA 15232.
authors.forename: Karen
authors.initials: K
authors.lastname: Schoedel
authors.affiliation: Department of Pathology, Presbyterian Shadyside Hospitals, University of Pittsburgh Medical Center, Pittsburgh, PA 15232.
authors.forename: Oleksandr
authors.initials: O
authors.lastname: Yergiyev
authors.affiliation: Division of Surgical Oncology, Presbyterian Shadyside Hospitals, University of Pittsburgh Medical Center, Pittsburgh, PA 15232.
authors.forename: David
authors.initials: D
authors.lastname: Bartlett
authors.affiliation: Department of Pathology, Presbyterian Shadyside Hospitals, University of Pittsburgh Medical Center, Pittsburgh, PA 15232. Electronic address: raounm@upmc.edu.
authors.forename: Uma N M
authors.initials: UNM
authors.lastname: Rao
mesh_terms: D000046:Academic Medical Centers; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000235:genetics; D001706:Biopsy; D054337:Cell Dedifferentiation; D005260:Female; D005784:Gene Amplification; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D053208:Kaplan-Meier Estimate; D008080:Liposarcoma / Q000235:genetics / Q000401:mortality / Q000473:pathology* / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D008938:Mitosis; D009336:Necrosis; D060787:Neoplasm Grading; D009362:Neoplasm Metastasis; D010414:Pennsylvania; D011237:Predictive Value of Tests; D051736:Proto-Oncogene Proteins c-mdm2 / Q000235:genetics; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome; D047368:Tumor Burden
chemical_list: D014408:Biomarkers, Tumor; C497206:MDM2 protein, human; D051736:Proto-Oncogene Proteins c-mdm2
keywords: High-grade dedifferentiated liposarcoma; Histological grade; Low-grade dedifferentiated liposarcoma; MDM2; Myxoid liposarcoma; Survival