Skull base chordomas account for less than 0.2% and chondrosarcomas for less than 0.15% of all intracranial tumors. Although their clinical and imaging presentation is similar, they derive from different origins. Chordomas arise from embryonic remnants of the primitive notochord and chondrosarcomas from primitive mesenchymal cells or from the embryonic rest of the cranial cartilaginous matrix. Both entities are characterized by infiltration and destruction of surrounding bone and soft tissue and a high locoregional recurrence rate. Chondrosarcomas, when treated with similar complex strategies, display a much better prognosis then chordomas. The overall survival is approximately 65% for chordomas and 80% for chondrosarcomas at 5 years and 30% and 50% respectively at 10 years. Chordomas are divided into three histological types: classical (conventional), chondroid, and dedifferentiated. Chondrosarcomas have conventional, mesenchymal, clear cell, and dedifferentiated subgroups. Both tumor entities often present with nonspecific symptoms and headaches are the most reported initial symptom. Computed tomography and magnetic resonance imaging are required for defining localization and extent of tumor growth. The treatment philosophy is to maximize tumor resection, minimize morbidity and preserve function. Neurosurgical approaches commonly used for the resection of intracranial chordomas and chondrosarcomas are transsphenoidal, transbasal, cranio-orbitozygomatic, transzygomatic extended middle fossa, transcondylar and transmaxillary approaches. Chordomas and chondrosarcomas are not sensitive to chemotherapy and there are no approved drugs for their treatment. The present treatment concept is a combination of surgical resection with a maximal excision and preserving patients’ quality of life by adjuvant radiotherapy for both, chordomas and chondrosarcomas.


中文翻译：

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颅底脊索瘤和软骨肉瘤。

在所有颅内肿瘤中，颅底脊索瘤占不到0.2％，软骨肉瘤占不到0.15％。尽管它们的临床表现和影像学表现相似，但它们起源不同。脊索瘤起源于原始脊索的残余残余物和原始间充质细胞或颅软骨基质的胚胎其余部分的软骨肉瘤。这两个实体的特征都是周围骨和软组织的浸润和破坏，局部复发率高。如果采用相似的复杂策略治疗软骨肉瘤，则其预后要比脊索瘤好得多。5年时脊索瘤的总生存率约为65％，软骨肉瘤的总生存率约为80％，而10年时的总生存率分别约为30％和50％。脊索瘤分为三种组织学类型：经典（传统），软骨样和去分化的。软骨肉瘤具有常规，间质，透明细胞和去分化亚组。两种肿瘤实体通常都表现出非特异性症状，头痛是最常报告的初始症状。需要计算机断层扫描和磁共振成像来确定肿瘤生长的位置和程度。治疗理念是最大程度地切除肿瘤，降低发病率并保持功能。通常用于颅内脊索瘤和软骨肉瘤切除术的神经外科方法有经蝶窦，经基底，颅眶oz，经zy，扩展中窝，经con和经上颌。脊索瘤和软骨肉瘤对化疗不敏感，也没有批准用于治疗的药物。