Bisceglia Michele, D'Angelo Vincenzo Antonio, Guglielmi Giuseppe, Dor David Ben, Pasquinelli Gianandrea
Department of Pathology, Division of Anatomic Pathology, IRCCS Casa Sollievo della Sofferenza Hospital, I-71013 San Giovanni Rotondo (FG), Italy.
Ann Diagn Pathol. 2007 Aug;11(4):262-73. doi: 10.1016/j.anndiagpath.2006.09.002.
A case of spinal thoracic chordoma involving the T9 vertebra in a 70-year-old male patient, destroying the vertebral body and invading the vertebral canal with compression of the spinal cord, is presented. The patient was referred to our neurosurgical unit with a history of an irradiated metastatic adenocarcinoma to the thoracic vertebra, a diagnosis that was rendered 3 years earlier at another hospital on presentation. This misdiagnosis was likely due to the absolute rarity of thoracic vertebral chordomas (2%-3% of all chordomas), the higher frequency of metastatic deposits to the vertebrae from visceral cancers in the elderly, the limited amount of biopsy material available for histologic examination, and the epithelial phenotype of the tumor (keratin/EMA positive). The patient underwent second palliative surgery with subtotal piecemeal removal of the tumor bringing relief of the neurologic symptoms. The bulk of the tumor was represented by a high-grade pleomorphic sarcoma with adjacent areas of atypical chordoma. Small foci of conventional chordoma were also found. The previous histologic slides were also reviewed, which were consistent with the areas of atypical chordoma. Small targeted tissue fragments from areas of (atypical) chordoma and from sarcomatous areas were recovered for electron microscopy. The fine features of chordoma and focal rhabdomyoblastic differentiation were found with the latter retrospectively supported by immunohistochemical detection of striated muscle markers. A final diagnosis of dedifferentiated chordoma with rhabdomyoblastic differentiation was finally established. Rhabdomyoblastic metaplasia is a novelty in dedifferentiated chordoma. The patient died after 5 months. Autopsy was not requested.
本文报告一例70岁男性患者的胸椎脊索瘤，累及T9椎体，破坏椎体并侵入椎管，压迫脊髓。该患者因胸椎曾接受过放射治疗的转移性腺癌病史转诊至我们的神经外科，此诊断是3年前在另一家医院初诊时做出的。这种误诊可能是由于胸椎脊索瘤极为罕见（占所有脊索瘤的2%-3%）、老年人内脏癌转移至椎体的频率较高、可用于组织学检查的活检材料有限以及肿瘤的上皮表型（角蛋白/上皮膜抗原阳性）。患者接受了二次姑息性手术，分块次全切除肿瘤，神经症状得到缓解。肿瘤大部分为高级别多形性肉瘤，伴有相邻的非典型脊索瘤区域。还发现了小灶性的经典脊索瘤。对之前的组织学切片进行复查，结果与非典型脊索瘤区域相符。从（非典型）脊索瘤区域和肉瘤区域获取小的靶向组织碎片用于电子显微镜检查。发现了脊索瘤的精细特征以及局灶性横纹肌母细胞分化，后者经免疫组化检测横纹肌标记物得到回顾性支持。最终确诊为伴有横纹肌母细胞分化的去分化脊索瘤。横纹肌母细胞化生在去分化脊索瘤中是一种新现象。患者在5个月后死亡。未要求进行尸检。
