Chapter 49 - Chordomas and Other Skull Base Tumors

Abstract

The list of differential considerations of lesions of the central skull base is long and includes many common tumors such as meningiomas and metastatic disease, which are discussed elsewhere in this book. In this chapter, we review the differential list of skull base tumors and discuss in more detail chordomas and to a lesser degree chondrosarcomas, two rare malignant lesions that classically involve the skull base. Although magnetic resonance imaging (MRI) has become the examination of choice in evaluation of intracranial tumors, in the skull base, computed tomography (CT) and MRI have complementary roles. CT is better at defining the complex bony anatomy and extent of bony involvement and MRI, because of its superior soft tissue contrast and multiplanar capability, is better at delineating the location, anatomic extension, and defining involvement of adjacent, critical neural, and vascular structures such as the cavernous sinus, optic chiasm, basilar artery and brain stem, for example. Although imaging studies cannot reliably distinguish chordoma from chondrosarcoma or other skull base lesions, defining the location and extent of the lesion are important factors in determining the optimal the surgical approach and in effective treatment planning. This is critical given that radical resection is the key factor in longer survival and improved quality of life.