Tumor thickness is an important prognostic factor in tumors outside of the upper aerodigestive tract, such as cutaneous melanoma, colorectal carcinoma, and cervical carcinoma. Some studies have also suggested that tumor thickness may have similar prognostic value in the upper aerodigestive tract. This study examined the relationship between tumor thickness (measured with an ocular micrometer) and nodal disease and that between tumor thickness and survival in 44 patients with soft palate epidermoid carcinoma. There was a significant correlation between tumor thickness and nodal disease. None of the 24 lesions less than or equal to 2.86 mm had cervical adenopathy. All of the 15 lesions greater than or equal to 3.12 mm had palpable adenopathy. Tumor thickness correlated more directly with nodal disease than did T stage. Thicker lesions were associated with poorer survival. Tumor thickness is an important parameter in the head and neck and deserves further study.