Dedifferentiated Extraskeletal Myxoid Chondrosarcoma of the Masticator Space: A Case Report.
10.4132/KoreanJPathol.2011.45.S1.S101
- Author:
Geunyoung JUNG
;
Kyung Ja CHO
;
Seung Ho CHOI
;
Mi Jung KIM
- Publication Type:Case Report
- Keywords:
Extraskeletal myxoid chondrosarcoma;
Cell dedifferentiation;
Masticator space
- MeSH:
Actins;
Aged;
Cell Dedifferentiation;
Chondrosarcoma;
Desmin;
Female;
Humans;
Keratins;
Magnetic Resonance Imaging;
Muscle, Smooth;
Necrosis;
S100 Proteins;
Tubulin
- From:Korean Journal of Pathology
2011;45(Suppl 1):S101-S105
- CountryRepublic of Korea
- Language:English
-
Abstract:
We describe a 69-year-old woman who presented with a dedifferentiated extraskeletal myxoid chondrosarcoma arising in the left masticator space. Computed tomography and magnetic resonance imaging revealed a 5 cm sized mass in the left masticator space. Histologically, the tumor consisted of two distinct areas. The less cellular area was a low-grade extraskeletal myxoid chondrosarcoma, composed of strands or cords of uniform spindle cells and abundant myxoid stroma. The more cellular, dedifferentiated area corresponded to a high grade myxofibrosarcoma, consisting of anaplastic tumor cells in myxoid stroma and geographic necrosis. The tumor cells of the former area were positive for S-100 protein, microtubule-associated protein-2 (MAP-2) and class III beta-tubulin, but negative for cytokeratin, smooth muscle actin, and desmin. The tumor cells in the latter, pleomorphic area showed MAP-2 and beta-tubulin immunoreactivity with a high Ki-67 labeling index. Based on its histologic and immunohistochemical features, the tumor was considered a dedifferentiated extraskeletal myxoid chondrosarcoma.
