An expandable vertebral body device, system, instrument, and methods of assembly and using the device, system, and instrument are disclosed. The vertebral body device includes a body with a first end and a second end, a first rotating member rotatably coupled to the first end, a second rotating member rotatably coupled to the second end, a first extension member moveably coupled to the first end, and a second extension member moveably coupled to the second end. The expandable cage system comprises a vertebral body device and an insertion instrument. Methods for assembling and using the vertebral body device and instrument are also disclosed.