Clinical Study Evaluating the Proper Surgical Safety Margin for Early Stage Oral Tongue Cancers

Randomization * The randomized allocation table was made by stratified block randomization methods with 1:1 ratio according to each participating surgeon and tumor stage. * Baseline number (BN) should be provided to the subjects in the order of the date of surgery. Surgical Procedure * The study includes T1-2N0 oral tongue cancer patients. For the management of the primary lesion, wide resection with 1.0- or 1.5-cm surgical safety margin should be performed according to the results of study allocation. * Neck management can be resection of primary tumor without neck dissection, with ipsilateral or bilateral neck dissection (guided by tumor location) or with sentinel lymph node biopsy, according to the NCCN guideline (version 1.2021). Evaluation of the surgical safety margin * The surgical safety margin should be meticulously evaluated in the pathology specimens in all directions. * The surgical margins less than 0.3 or 0.5 cm in final pathology results are considered as the close surgical margin. Adjuvant Treatment * The adjuvant treatments either radiotherapy or chemoradiotherapy are conducted if indicated following the NCCN guideline. * The follow-up after completion of the definitive treatment are made following the NCCN guideline. Efficacy evaluation * The primary outcomes are determined with 2-year local control rates after the completion of the curative treatments. * The secondary outcomes are determined with the 5-year disease-free survival rates and speech/articulation functional analysis.