Zhang Ming, Zhang Wei, Li Qiang, Qu Jian-Li, Zhang Guo-Feng
Department of Pathology, Yantai Yantaishan Hospital Yantai, Shandong, China.
Department of Bone Tumor Surgery, Yantai Yantaishan Hospital Yantai, Shandong, China.
Int J Clin Exp Pathol. 2014 Jan 15;7(2):797-800. eCollection 2014.
Small-cell extraskeletal osteosarcoma is extremely rare and consists of sheets of small round cells with variable amounts of osteoid. This tumor is often difficult to diagnose when tissue samples do not include recognizable osteoid. Only four cases have been reported in English and none in Chinese. We report a typical case of small-cell extraskeletal osteosarcoma occurring in the left leg of a 40-year-old female. Laboratory results were within normal limits. Magnetic resonance imaging demonstrated a soft tissue mass measuring 36 mm × 18 mm in the medial lateral aspect of left limb. The initial histological findings led to a misdiagnosis because the first fine-needle biopsy was randomized and incomplete. However, an open surgical specimen showed recognizable osteoid, which enabled us to make a definitive diagnosis. We also present clinical, radiologic and pathologic features of this case.
小细胞骨外骨肉瘤极为罕见，由成片的小圆形细胞和数量不等的类骨质组成。当组织样本中不包含可识别的类骨质时，这种肿瘤通常难以诊断。英文报道仅有4例，中文尚无报道。我们报告1例发生于40岁女性左腿的典型小细胞骨外骨肉瘤病例。实验室检查结果均在正常范围内。磁共振成像显示左下肢中外侧有一大小为36 mm×18 mm的软组织肿块。最初的组织学检查结果导致误诊，因为首次细针穿刺活检随机且不完整。然而，手术切除标本显示有可识别的类骨质，从而得以明确诊断。我们还展示了该病例的临床、影像学和病理学特征。
