BACKGROUND: For papillary thyroid cancer, lymph node excision may be less important for smaller tumors and rather limited node excision might be sufficient to prevent recurrence. METHODS: We compared patients who had undergone modified radical neck dissection with patients who had undergone limited node basin excision. Between 1967 and 1996, 4966 patients at our institution had resection of pure papillary carcinoma tumors larger than 11 mm. RESULTS: In patients whose tumors were larger than 25 mm without local adhesion, modified radical neck dissection had a significantly better prognosis compared to that of more limited node excision. For patients with a primary tumor larger than 11 mm, modified radical had a better prognosis than partial node excision only if there was adhesion or invasion to the recurrent nerve, jugular vein, common carotid artery, vagus nerve, or trachea. CONCLUSION: The size of papillary cancer of the thyroid directly affects prognosis and the role of nodal dissection.