Due to a lack of large clinical series in the literature of chondrosarcomas and hydatid disease presenting as mediastinal dumbbell tumours, clinicians have limited experience on this topic. We present three unusual cases of dumbbell tumour involving the spinal canal; two patients had chondrosarcoma originating from Th8-Th9 and Th10-Th12; one patient had a hydatid cyst at Th5-Th6. We performed a single-stage combined thoracic-neurosurgical approach in two patients, and a double-staged approach in one patient. During the intraspinal dissection, an operating microscope was used under electrophysiological monitoring. Spinal canal reconstruction was not required for any of the cases. Preoperative knowledge of neuroforaminal extension and the relations between the tumour and adjacent neural-vascular structures is essential to prevent spinal cord damage and plan the surgical approach. In chondrosarcomas, prognosis depends on patient age, histological grade, extent of surgery and response to radiotherapy and/or chemotherapy. In this article, the diagnostic and surgical difficulties of these unusual tumours and current treatment modalities are discussed with a review of the relevant literature.