Transfer of the patient to the operating theater. Active patient identification. Team time-out and initial consultation with anesthesia colleagues. Induction of anesthesia by the colleagues. 0° tracheoscopy by the surgeon: the trachea is free of irritation and inconspicuous on all sides, the trachea is visible up to the carina. Intubation of the patient by the anesthesia colleagues. Positioning of the patient in the head reclination position and insertion of the small bore tube size C. Inspection of the hypopharynx, first on the left, then on the right side. The piriform sinus must be freely unfolded on both sides and free of masses. Now adjust the endolarynx. Here also inconspicuous conditions. Withdrawal of the small aqueous humor tube and inspection of the epiglottis and vallecula. Here also inconspicuous conditions. Insertion of the mouth retractor and inspection of the oropharynx. In the area of the right base of the tongue, a cherry stone-sized mass measuring approx. 1 cm was found, which was palpable. The other regions of the oropharynx were unremarkable. Demonstration of the findings to <CLINICIAN_NAME> and decision to perform an excisional biopsy or tumor resection. Incision of the mucosa with an electric needle. Dissection with scissors through the tongue muscles under constant palpatory control. Bipolar coagulation of individual vessels. It becomes apparent that the tumor extends to the glossotonsillar groove on the right side. Therefore, generous tumor resection also in the area of the glossotonsillar groove so that the parapharyngeal fatty tissue is exposed. Removal of the tumor with healthy marginal tissue without complications. In addition, a resection is made in the area of the glossotonsillar groove, as the resection was only just made here macroscopically. The specimen is sent for histological frozen section examination. Feedback from the pathologist at 12:30: Main tumor specimen with a squamous cell carcinoma (forming a margin to the glossotonsillar groove). In the resection in the area of the glossotonsillar groove, however, resected R0. Due to the deep resection down to the parapharyngeal fat on the right side, the planned neck dissection on the right was not performed. This should be performed twice in 3 weeks in order to avoid an extensive defect. The patient is now repositioned and the decision is made to perform the neck dissection on the left side. To do this, make a skin incision in the area of a skin fold along the sternocleidomastoid muscle. Cut through the cutaneous and subcutaneous tissue. Dissection of the platysma. Subplatysmal dissection cranially until the submandibular gland is exposed. Subplatysmal dissection caudally to expose the omohyoid muscle. Free preparation of the anterior border of the sternocleidomastoid muscle down to the depth. Identification of the accessor nerve and exposure of the nerve. This can be safely spared. Identification of the posterior venter of the digastric muscle. Division of the neck preparation in the medial and lateral part on the internal jugular vein. Reliable identification of the vagus nerve and the common carotid artery. Identification of the hypoglossal nerve. Now detach the neck preparation from cranial to caudal and pull through under the accessorius nerve. The neck preparation is carefully dissected from the deep cervical fascia. The branches of the cervical plexus can be safely spared. Check the wound again: dry wound conditions prevail everywhere. Irrigation with Ringer. Application of a Redon drainage and two-layer wound closure. Recheck of the enoral findings. There is no further bleeding enorally. The operation is completed without complications.