Radiation Therapy for Chondrosarcoma

Abstract

Although surgical resection is the mainstay of treatment for primary chondrosarcoma, complete resection with negative margins is often difficult to achieve, especially in the skull base and in the spine. Radiation therapy is an essential component of the local disease control armamentarium. Radiation has a role in the adjuvant setting after incomplete resection, as a definitive modality when resection is not feasible, as a tool for salvage after recurrence, and in the setting of metastatic disease. However, radiation therapy delivery in these locations is also challenging because effective treatment requires high cumulative doses (~70 Gy or higher), and the treatment target is often adjacent to critical structures (e.g., brainstem, spinal cord, cranial nerves). Advanced radiation treatment modalities are critical to achieve the appropriate dose and to spare critical structures. Patients should be considered for particle-based therapies (proton or carbon ion) when possible. Photon-based therapies should be delivered using advanced image guidance and intensity-modulated radiotherapy. For smaller tumors in the skull base, stereotactic radiosurgery should be considered. Radiation therapy is often administered postoperatively, though combined preoperative and postoperative strategies have been effective in the spine and the pelvis. A multidisciplinary approach in an experienced center is recommended for optimal treatment of this rare malignancy.