Stage IV is divided into stage IVA, stage IVB, and stage IVC. In stage IVB, (1) cancer has spread to the space in front of the spinal column, surrounds the carotid artery, or has spread to parts of the chest; cancer may have spread to one or more lymph nodes anywhere in the neck and the lymph nodes may be any size; or (2) cancer has spread to a lymph node that is larger than 6 centimeters and may have spread as far as the space in front of the spinal column, around the carotid artery, or to parts of the chest. The vocal cords may not move normally.