Laryngeal cancer that crosses the ventricle and anterior commissure in a vertical direction invades laryngeal framework in a high percentage of cases (76%, 32 of 42 cases reported here). If the tumor merely crosses the level of the ventricle behind its posterior end, laryngeal framework is not invaded. Invasion of laryngeal framework is related to size of primary lesion. Invasion rarely occurs in lesions below 2 cm in greatest diameter, but occurs in about three fourths of those cases larger than 3 cm.
Degree of differentiation of primary lesion showed no relationship to invasion of laryngeal framework. By contrast, cervical lymph node involvement occurred with 63% (5 of 8) of poorly differentiated lesions, as compared with 23% (10 of 42) of well or moderately well differentiated. Metastasis occurred more than twice as often if the primary lesion was over 4 cm in any dimension.