Stages of throat cancer
The stages of throat cancer depend on the location where the tumor has started.
The staging system most often used for throat cancer is the TNM system of the American Joint Committee on Cancer (AJCC). In these staging systems, three key pieces of information are used
- T (tumor): It refers to the size of the original tumor.
- N (node): It describes whether cancer has spread to the lymph nodes.
- M (metastasis): It refers to the spreading of cancer to other parts of the body.
A number (0-4) or the letter X is allocated to each factor. A higher number means the cancer is more advanced. For instance, a T1 score refers to a smaller tumor than a T2 score. The letter X indicates that the information could not be assessed.
The stages of throat cancer depend on the location where the tumor has started. It could be
- Supraglottis (the area above the vocal cords)
- Glottis (the area that includes the vocal cords)
- Subglottis (the area below the vocal cords)
Table. Stages of throat cancer depending on its location
Stages
Stages Grouping
Supraglottis
Glottis
Subglottis
0
Tis
N0
M0
The tumor is only in the top layer of cells lining the inside of the larynx or voice-box (Tis). Cancer has not spread to nearby lymph nodes (N0) or distant parts of the body (M0).
Same
Same
I
T1
N0
M0
The tumor has grown deeper into one part of the supraglottis (T1). Cancer has not spread to the nearby lymph nodes (N0) or distant parts of the body (M0).
The tumor is limited to the vocal cords, but it does not affect the movement of the cords (T1). Cancer has not spread to the nearby lymph nodes (N0) or distant parts of the body (M0)
The tumor is only in the subglottis (T1). Cancer has not spread to the nearby lymph nodes (N0) or distant parts of the body (M0).
II
T2
N0
M0
The tumor has grown deeper into more than one part of the supraglottis (or glottis). The vocal cord isn’t affected (T2).
Cancer has not spread to nearby lymph nodes (N0) or distant parts of the body (M0).
The tumor has spread to the supraglottis and/or the subglottis. The tumor may also affect the movement of the vocal cord (T2). Cancer has not spread to nearby lymph nodes (N0) or distant parts of the body (M0).
The tumor has grown into the vocal cord that may or may not move normally (T2). Cancer has not spread to nearby lymph nodes (N0) or distant parts of the body (M0).
III
T3
N0
M0
The tumor is still only in the larynx, but it has caused the vocal cord to stop moving (T3). Cancer has not spread to the nearby lymph nodes (N0) or to distant parts of the body (M0)
Same
Same
IVA
T4a
N0 or N1
M0
The tumor has grown through the thyroid cartilage and/or is growing into tissues beyond the throat (T4a). Cancer has not spread to the nearby lymph nodes (N0), or it has spread to a single lymph node that is no larger than 3 centimeters across (N1). Cancer has not spread to distant parts of the body (M0).
The tumor has spread to the thyroid cartilage and/or the tissue beyond the larynx (T4a). Cancer has not spread to nearby lymph nodes (N0), or it has spread to a single lymph node on the same side of the neck as the tumor, which is no larger than 3 centimeters across (N1). Cancer has not spread to distant parts of the body (M0).
The tumor is growing through the cricoid or thyroid cartilage and/or into structures beyond the throat.
IVB
T4b
Any N
M0
The tumor has spread to the area in front of the spine (prevertebral space), chest area or it encases the arteries (T4b). Cancer might or might not have spread to nearby lymph nodes (any N). It has not spread to distant parts of the body (M0).
Same
Same
IVC
Any T
Any N
M1
The tumor might or might not have grown into structures outside the larynx, and it might or might not have affected a vocal cord (any T). Cancer might or might not have spread to nearby lymph nodes (any N). Cancer has spread to distant parts of the body (M1).
Same
Same