Dedifferentiated Chondrosarcoma in the Scapula

Full Article

ACW Tam, ATS Chan, JCK Lee, FMF Cheung

Hong Kong J Radiol 2011;14:229-33

Dedifferentiated chondrosarcoma is a rare but highly malignant form of chondrosarcoma with grave prognosis. Early and accurate diagnosis followed by radical surgery seems the only treatment to improve survival. We report a case of dedifferentiated chondrosarcoma in the scapula of a 55-year-old woman presenting with non-specific left shoulder pain. Radiography, computed tomography, and magnetic resonance imaging showed an expansile osteolytic lesion with cortical erosion and internal punctate calcification involving coracoid and glenoid processes. Soft tissue components of the lesion appeared to have invaded the rotator cuff muscles. Computed tomography–guided biopsy confirmed the diagnosis and the tumour was excised with the shoulder joint. Histopathology of the specimen demonstrated intramedullary tumour showing conventional chondrosarcoma admixed with a malignant fibrous histiocytoma-like spindle cell sarcoma. The features were compatible with dedifferentiated chondrosarcoma arising from a conventional chondrosarcoma. Having reviewed the clinical and radiological features of dedifferentiated chondrosarcoma, we stress the importance of radiological imaging features to identify tumour bimorphism suggestive of the diagnosis, and select the site to biopsy.





去分化型軟骨肉瘤是一種罕見的高惡性度腫瘤,預後差。盡早為病人作出準確的診斷,繼而進行根 治性手術似乎是唯一可改善存活期的方法。本文報告一名55歲肩胛骨去分化型軟骨肉瘤女性患者, 病發時有左肩胛骨疼痛。放射檢查、CT及磁共振影像均發現膨脹性溶骨灶,並有皮質中斷及牽涉鳥 口突起及關節盂的內部小點狀鈣化灶。而病灶的軟組織成分似乎經已侵佔肩袖肌。經CT引導下穿刺 確診,並把腫瘤及肩關節一併切除。病變組織學顯示髓內腫瘤切除樣本有一般軟骨肉瘤的特徵,並 呈類似惡性纖維組織細胞瘤的梭細胞癌。這些症狀都符合由傳統軟骨肉瘤演變成去分化型軟骨肉瘤 的特徵。回顧去分化型軟骨肉瘤的臨床及放射學特徵,可以知道認識雙相腫瘤的放射學徵狀有助確 診病情及選擇穿刺的位置。