Case: A 70-year-old woman underwent radiological evaluation for a longstanding, slowly enlarging mass at the back of her neck. Let us begin with the plain radiograph: Figure 1. Lateral radiograph showing the mass at the back of the neck. We see a smoothly contoured mass producing an outward bulge in the posterior neck region. Its relatively radiolucent appearance suggests fat content. However, its internal structure is not entirely homogeneous; a few millimetric radiopaque fo