Stage IV nasal cavity and ethmoid sinus cancer is divided into stages IVA, IVB, and IVC. In stage IVB, cancer (1) has spread to any of the following: the back of the eye, brain, middle parts of the skull, nerves in the head that go to the brain, upper part of the throat behind the nose, and/or the base of the skull, and cancer may be found in one or more lymph nodes of any size, anywhere in the neck; or (2) is found in a lymph node larger than 6 centimeters. Cancer may also be found anywhere in or near the nasal cavity and ethmoid sinus.