First consultation with the anesthetist. Then advance the 0° optic through the glottic plane into the trachea. Inconspicuous mucosal conditions in the area of the trachea up to the exit of the segmental bronchi. Now ......... Patients. Advance the flexible esophagoscope into the stomach. Inconspicuous mucosal conditions in the area of the stomach. Mirroring back. No abnormalities in the area of the esophagus. Now inspect the hypopharynx on both sides and the postcricoid region. Inconspicuous mucosal conditions on all sides. Inspection of the larynx after insertion of the small drainage tube. In the subglottis, glottis and supraglottis areas, the mucous membrane conditions are unremarkable. Inspection of the oropharynx and nasopharynx after pulling up the soft palate. All inspections with the aid of the endoscope or microscope. Now position the patient. Insert the mouth retractor and pull out the tongue. The described tongue margin carcinoma on the left with an extension of approx. 2.5 cm, thus clinically T2. Careful resection of this tumor in all planes in the healthy area. Bleeding is stopped with bipolar coagulation or by ligation. The specimen is completely removed and marked. The specimen is marked and sent for pathological frozen section examination. A resection in sano is confirmed at all levels. Finally, adequate hemostasis. Dry conditions at the end of the operation. Now reposition the patient. Local anesthesia is administered in the area of the left neck, abjodation, covering of the surgical area. Skin incision from the tip of the mastoid to the clavicle. Dissection of the subcutaneous tissue, dissection of the platysma, exposure of the external jugular vein, exposure of the auricular nerve. Both the external jugular vein and the auricular nerve are displaced cranially and re-embedded in their original bed at the end of the operation. Exposure of the sternocleidomastoid muscle, exposure of the accessorius nerve, exposure of the common carotid artery, internal and external carotid artery, internal jugular vein, hyperglossal nerve and vagus nerve. There are larger lymph nodes in the area of level II as well as in the area of level IV and V, whereby the macroscopic aspect appears rather inconspicuous. Now expose the posterior venter, the digastric mucus and clear out levels IV and V while sparing the accessorius nerve and the cervical and brachial plexus. Deposit the preparation at the level of the omohyoid muscle. Now remove the ........... connective tissue in the area of levels II and III. The capsule of the submandibular gland is exposed and also resected. This results in a modified level II-V radical neck dissection. Irrigation of the wound with water and hydrogen. Insertion of a Redon drainage, wound closure in layers. Final discussion with the anesthetist. Further procedure depending on the histology.