OK, so now you are a T2N1M0. An ENT is a surgically oriented doctor and his preference is based on his education and personal experience. You need a consultation with a radiation doctor to give you a balanced perspective. You have no doubt read my many posts here regarding recurrences and how I feel that that is a misnomer for what is actually an occult metastasis that rears its ugly head later. Combined therapies have better long-term outcomes. I offer you this quote from the Journal of the National Cancer Institute just a couple of months ago.
"Treatment of the neck is a highly controversial point, but many authors feel that elective treatment of the neck is indicated even for T1 neoplasms based on the incidence of occult metastases, 20-33% in most series, as well as the poor results with a later salvage procedure. ***Most authors advocate elective treatment of the neck for stage II disease (T2N0) for the same reasons, and the incidence of occult metastases in this group is even higher. Supraomohyoid neck dissection is often the procedure of choice for management of the clinically negative neck, with radiation being reserved for those patients with lymphatic involvement, especially if there is evidence of capsular invasion.*** The problem of understaging has been frequently cited in reference to carcinomas of the oral tongue, and reports may be found addressing specific factors which may indicate those patients with early lesions most likely to harbor occult metastases, and thus be the most likely to benefit from prophylactic treatment of the neck. Such factors as depth of penetration, histologic grade, perineural or perivascular invasion have all been investigated but none are widely accepted to have reliable prognostic value."
(The marked emphasis is mine so you don't get lost in everything else.) The point is, up to 33% of those with no visible cervical involvement harbor a metastasis in that area. You have one for sure, though caught early. Just because current scanning technology, MRI and CT, do not see it now, does not mean that it isn