Neck Observation or Elective Neck Dissection in CT1N0M0 OSCC

"In the experimental arm: the neck management is neck observation, simultaneous elective neck dissection is not performed during the surgical resection of primary lesion. The patients will be followed up every two months for at least two years, focusing on the lymph node metastasis and local recurrence. Ultrasonography, CT scan, and/or MRI will be used to detect lesions.~In the control arm: the neck management is elective neck dissection. Simultaneous elective neck dissection is performed during the surgical resection of primary lesion. The patients will be followed up every two months for at least two years, focusing on the lymph node metastasis and local recurrence. Ultrasonography, CT scan, and/or MRI will be used to detect lesions."