Table 3. McCaffrey system (2).

Stage	Characteristics
1	Lesion confined to the subglottis or trachea that are less than 1 cm long
2	Subglottic lesion longer than 1 cm, within the cricoid ring, not extending to the glottis or trachea
3	Subglottic lesion that extends into the upper trachea but does not involve the glottis
4	Lesion involving the glottis with fixations or paralysis of one or both vocal cords