Retroperitoneal dedifferentiated liposarcoma with rhabdomyoblastic differentiation: a clinicopathological analysis
10.3760/cma.j.issn.0529-5807.2018.02.003
- VernacularTitle: 腹膜后伴横纹肌分化的去分化脂肪肉瘤临床病理分析
- Author:
Lei LIU
1
;
Lihua WANG
;
Yubo REN
;
Xiaosong RAO
;
Shaomin YANG
Author Information
1. Department of Pathology, Peking University International Hospital, Beijing 102206, China
- Publication Type:Journal Article
- Keywords:
Retroperitoneal neoplasms;
Liposarcoma;
Muscle, striated;
Immunohistochemistry
- From:
Chinese Journal of Pathology
2018;47(2):94-98
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To investigate the clinicopathological features, differential diagnosis, treatment and prognosis of dedifferentiated liposarcoma with rhabdomyoblastic differentiation.
Methods:Six cases of retroperitoneal dedifferentiated liposarcoma with rhabdomyoblastic features were collected from December 2014 to August 2017 at Peking University International Hospital. The clinical manifestations, histomorphology, immunophenotype, treatment and follow-up data were analyzed, and relevant literature reviewed.
Results:The six patients included two males and four females, with age range of 47 to 66 years (mean 56 years). One case was primary and the five cases were recurred; four cases received radiotherapy and/or chemotherapy. The tumor diameters were 10 to 30 cm. Microscopically, the dedifferentiated areas were well demarcated from the well-differentiated areas, and resembled malignant fibrous histiocytoma, fibrosarcoma or solitary fibrous tumor with obvious mitotic figures or necrosis. Rhabdomyoblastic cells made up 10% to 30% of dedifferentiated area, and were scattered or focally distributed, being rounded, band-like or spindled, mostly with abundant eosinophilic cytoplasm. No striated structure was found, and the nucleis were rounded, oval or irregular shape with central or eccentric prominent nucleoli. Rare rhabdomyoblastic cells were lymphocytoid. The tumors encroached the muscular layer of intestinal wall in two cases and perirenal adipose tissue in one case. By immunohistochemical staining, the rhabdomyoblastic cells of all cases were all positive for desmin, myogenin, myoD1 and SMA; S-100 protein was expressed in one case (1/6). Well-differentiated area in two cases and dedifferentiated areas in all six cases were positive for MDM2, CDK4 and p16. After resection of the tumor and adjacent organs, one case recurred three months later, but there was no distant metastasis.
Conclusions:Dedifferentiated liposarcoma with rhabdomyoblastic differentiation is a rare dedifferentiated liposarcoma. Pathological diagnosis is based on morphology, with supplementary immunohistochemical or molecular evaluation for further differential diagnosis. Multiple relapses may occur after surgical ablation plus adjuvant therapy.
