Stage IV is divided into stage IVA, stage IVB, and stage IVC. In stage IVA, (1) cancer has spread through the thyroid cartilage and/or has spread to tissues beyond the larynx, such as the neck, trachea, thyroid, or esophagus; cancer may have spread to one lymph node on the same side of the neck as the original tumor and the lymph node is 3 centimeters or smaller; or (2) cancer has spread to one lymph node on the same side of the neck as the original tumor and the lymph node is larger than 3 centimeters but not larger than 6 centimeters, or has spread to more than one lymph node anywhere in the neck with none larger than 6 centimeters; cancer may have spread to tissues beyond the larynx, such as the neck, trachea, thyroid, or esophagus. The vocal cords may not move normally.