Late – Stage Laryngeal Carcinoma (T3-T4 ) Has A High Incidence Of Cervical Metastasis . The Incidence Of Subclinical Metastasis Is Not Well Described In None Irradiation And Irradiation Patients Initially Clinically T3,T4) With Negative Nodes Of The Neck ,And The Treatment Of These Patients Is Contraversal. Identify The Incidence Of Subclinical Metastatic Disease In (T3,T4) ) With Negative Nodes Of The Neck Undergoing Functional Neck Dissections With Laryngectomy. And Identify The Incidence Of Subclinical Metastatic Disease In Those Patients Who Faild Radiotherapy. Are There Any Benefits Of Cts In Those Patients? .And What Is The Most Aproprait Therapy?.