Muti instuitutional clinical study of transoral robotic surgery for laryngopharyngeal cancer

INTERVENTION: Transoral robotic surgery CONDITION: Laryngopharyngeal cancer PRIMARY OUTCOME: Positive surgical margin rate; NG tube or PEG dependency rate SECONDARY OUTCOME: Completion rate of surgery, hospitalzation; period, INCLUSION CRITERIA: 1) Single cancer lesion in mesopharynx, hypopharynx, or larynx 2) Diagnosed as squamous cell carcinoma 3) Fultill the following conditions regarding TNM a)Tis, T1, or T2 cancer b)N0 or non extracapsule invation N(+) after neck dissection more than 10 days prior to registration c)M0 4) Primary lesion has no adhesion with neiboring tissue and is movable 5) ECOG PS is 0, 1, or 2 6) Fulfill the following condition within 4 weeks prior to registration date Hb more than 8 g/dL Plt more than 50000/uL AST less than 120 IU/L ALT less than 120 IU/L Cre less than 1.5mg/dL 7) Obtained consent form from the candidate