Stage IV is divided into stages IVA, IVB, and IVC. In stage IVB, one of the following is found: (1) cancer has spread to the space in front of the spinal column and surrounds the carotid artery, or has spread to parts of the chest and may have spread to one or more lymph nodes anywhere in the neck (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. Vocal cords may not move normally.