Table 2.

T staging of supraglottic carcinoma

T1	Tumour limited to one subsite with normal vocal cord mobility
T2	Tumour involves mucosa of more than one supraglottic subsite or glottis or extralaryngeal mucosa (e.g. piriform sinus) with normal cord mobility
T3	Tumour limited to larynx with vocal cord fixation and/or invasion of postcricoid, pre-epiglottic region, paraglottic space and/or minor thyroid cartilage erosion (e.g. inner cortex)
T4a	Tumour involves tissues beyond the larynx and/or laryngeal cartilage (e.g. trachea, deep extrinsic tongue muscles, strap muscles, thyroid or oesophagus)
T4b	Tumour invades prevertebral space, encases carotid artery or invades mediastinal structures