Can neck irradiation be an alternative to neck dissection in early stage carcinoma oral tongue operated for primary alone? Experience from a single institute

Purpose: To study pattern of failure, locoregional control rates (LCR) and disease free survival (DFS) in post-operative patients of carcinoma oral tongue, and to study the impact of nodal dissection on DFS in stage I and II patients. Methods: 102 patients of carcinoma oral tongue treated between January 2009 and December 2013 were analyzed. All patients were operated for primary disease, but neck dissection was done in 78 (76.5%) patients only. However, radiation to primary site along with neck region was received by all patients. Pattern of failure, LCR and DFS were estimated. Results: At median follow up of 12 months, 10.8% patients failed locally, 10.8% in nodal region, 2.9% both at local and nodal site, and 5.9% patients failed distally. 2 year LCR and DFS was 71.2%, 90.9%, 79.5%, 0% and 55.2%, 64.4%, 57.8%, 0% in stage I, II, III, IV respectively. 2 year DFS in stage I patients, who underwent nodal dissection and post-operative radiation (14 patients) was 64.3% and in whom only neck irradiation was done (15 patients), it was 45.8%, however difference was not significant ( p = 0.5). But in stage II patients, 33 patients who underwent nodal dissection and post-operative radiation, 2 year DFS was 85.4% and it was 21.4% in 7 patients who underwent neck radiation only, and difference showed trend towards significance ( p = 0.05). 2 or more positive lymph nodes post dissection was the only poor prognostic factor that correlated with DFS ( p = 0.02) Conclusion: While in stage I, neck irradiation alone can be a possible alternative to neck dissection and post-operative radiation; for stage II, neck dissection is mandatory.