Glottis:

• T1-tumor limited to the vocal cords
  • T1a-tumor limited to one vocal cord
  • T1b-tumor involves both vocal cords
• T2-tumor extends to the supraglottis and/or subglottis and/or impaired vocal cord mobility
• T3-tumor with vocal cord fixation (a cord cannot move at all)
• T4-tumor invades outside of the larynx (trachea, soft tissues of the neck, etc.)

Supraglottis:

• T1-tumor limited to one subsite of the supraglottis with normal vocal cord mobility
• T2-tumor invades one adjacent site of the supraglottis or glottis or one region outside of the supraglottis without fixation of the vocal cords
• T3-tumor limited to the larynx with vocal cord fixation or invasion into the area behind the larynx or in front of the larynx
• T4- tumor invades outside of the larynx (trachea, soft tissues of the neck, etc.)

The "N" stage is as follows for any subsite:

• N0-no spread to lymph nodes
• N1-tumor spread to one lymph node on the same side as the tumor in the throat. Lymph node must be < 3 cm
• N2a-tumor spread to one lymph node on the same side as the tumor in the throat. Lymph node is between 3 and 6 cm
• N2b-tumor spread to more than one lymph nodes on the same side as the tumor in the throat, with none being >6 cm

• N2c-tumor spread to lymph nodes on both sides of the neck, with none being >6 cm
• N3-tumor spread to a lymph node when the lymph node is > 6 cm

• M0-no tumor spread to other organs
• M1-tumor spread to other organs

The overall stage is based on a combination of these T, N, and M parameters:

• Stage I-T1N0M0
• Stage II-T2N0M0
• Stage III-T1-3N1M0 or T3N0M0
• Stage IVA-T4N0-1M0 or Any T, N2M0
• Stage IVB-Any T, N3M0
• Stage IV-any M1