Transfer of the patient to the operating room, active patient identification, consultations with anesthesia colleagues. Therefore, carrying out the team time out. Induction of anesthesia and intubation by the anesthesia colleagues. Then insertion of the PEG gastric tube. Careful insertion of the flexible endoscope under air insufflation. Then positive diaphanoscopy loco typico. Subsequent skin disinfection of the abdomen and upper abdomen, infiltration anesthesia and placement of the PEG gastric tube using the thread pull-through technique without any problems by <CLINICIAN_NAME> and <CLINICIAN_NAME>. Preoperative administration of 3 g Unacid. The tumor is then resected by <CLINICIAN_NAME> . Adjustment of the base of the tongue by <CLINICIAN_NAME> with the spreading laryngoscope and the support. Use the microscope. The tumor of at least 1 cm in size described in the panendoscopy is seen in the cranial base of the tongue, not approaching the midline, but there is still questionable unstable mucosa at the caudal medial edge. Now set the laser to cw 8 watts. Mark the resection margins with the laser. Successive resection of the tumor using the laser with the aid of Blakesley. Attention is paid to the lateral vascular bundle. Laser resection is performed up to the borders of the oropharynx laterally and into the vallecula. The mass is then sent to the frozen section in toto with the markings cranial tongue base and lateral oropharyngeal side wall, caudal vallecula and medial. Repeated meticulous hemostasis, then dry wound conditions. The frozen section then shows a CIS forming a margin from 3 o'clock to 12 o'clock. Therefore, the resection is now performed by <CLINICIAN_NAME>. To do this, adjust the base of the tongue with the spreading laryngoscope and, with the aid of the support, adjust using a microscope and laser. The laser is set to 8 watts. Now successive resection. Final marginal samples are taken from 3 o'clock/ oropharyngeal side wall to 6 o'clock. A second margin sample from 6 o'clock to 9 o'clock, suture marking at 6 o'clock and third margin sample from 9 o'clock to 12 o'clock. The post-resection shows that the mucosa is completely normal; it is not possible to differentiate between CIS and normal mucosa. Then repeated hemostasis using monopolar coagulation, followed by re-inspection of the surgical site with the Kleinsasser tube. Occasionally targeted bipolar coagulation. There is now a large wound surface over the entire base of the tongue from the right to the opposite side and filling the entire vallecula. Here, however, the wound is dry. Subsequent transition to neck dissection on the right side. Infiltration anesthesia with a total of 20 ml Ultracaine in the area of the neck dissection incision on the right side and on the left side. Skin disinfection of the surgical area and sterile draping of the surgical area. Then mark the landmarks on both sides of the mastoid, jugulum, mandibular angle and mandibular margin and sternocleidomastoid anterior margin. Then mark the skin incisions on the right and left of the mastoid in an arched medial direction and towards the sternocleidomastoid in a caudal direction. Ensure that the incision is as symmetrical as possible on both sides. Now start on the right side. Cut through the cutaneous and subcutaneous tissue, cut through the platysma. Now develop the medial neck preparation and dissect subplatysmal using a scalpel. Expose the anterior margin of the sternocleidomastoid and dissect it caudally. Exposure of the accessorius nerve and sparing of the same. Exposure of the entire course of the jugular vein and protection of the same. This is conspicuously thin, with a jump in caliber only in the caudal part of level IV. Exposure of the cervical vein, which is also exposed and spared. Exposure of the omohyoid muscle and the digaster venter anteriorly and posteriorly and protection of the same. Exposure of the mandibular salivary gland. Exposure of the hypoglossal nerve and sparing of the same. Now resection of the medial neck preparation. Here 2 suspicious level II lymph nodes are noticed. These are resected in toto. Expose the internal and external bifurcation and the superior thyroid artery and spare them. Note: The auricularis magnus nerve was exposed and spared during the skin incision. A larger caliber branch of the external jugular vein was ligated. Now resection of the lateral triangle of the neck. Here, the vagus nerve is first exposed and spared, the accessorius triangle is resected cranial to the accessorius nerve, mobilization under the accessorius nerve. Dissection down to the plexus branches and resection of the lateral neck preparation from cranial to caudal up to level IV as well as level Va and b. The plexus branches are also spared. Removal of the lateral neck preparation. The facial vein could not be visualized. Now targeted bipolar coagulation, irrigation with H202 and Ringer. Increase in pressure to 160, targeted bipolar coagulation, otherwise very dry wound conditions. Application of a 10 redon and two-layer wound closure using subcutaneous and cutaneous sutures. Application of a pressure dressing. Turning to the opposite side. Identical procedure here. First cut through the cutaneous and subcutaneous tissue and the platysma with a scalpel. Expose the auricularis magnus nerve. Sparing of the same. Dissection of the branches of the external jugular vein and ligation of the same. The neck preparation is dissected subplatysmally. Expose the anterior sternocleidomastoid margin and dissect caudally. Exposure of the jugular vein and sparing of the same. Exposure of the accessorius nerve and sparing of the same. Exposure of the omohyoid muscle. Cranial dissection. Exposure of the digaster venter anteriorly and posteriorly as well as the mandibular salivary gland. Now resection of the medial neck preparation, exposing the cervical anus and the hypoglossal nerve, which is spared. Removal of the medial neck specimen. Resection of the lateral neck specimen. The carotid artery and the vagus are still exposed and spared. Level IIa, Va and III are also resected up to level IV. The plexus branches are exposed and spared. Then targeted bipolar coagulation, irrigation with H202 and Ringer. Increase the peep and pressure, then no further bleeding. Dry wound conditions. Insertion of a 10-gauge Redon and two-layer wound closure using subcutaneous and cutaneous sutures. Application of a pressure dressing. Now create a protective tracheostomy. To do this, mark the thyroid incisura, cricoid cartilage, jugulum and the planned skin incision 1 QF below the cricoid cartilage. Now make the skin incision of approx. 3 cm horizontally and cut through the skin and subcutaneous tissue. Expose a larger caliber vein, which is ligated. Dissection of the infrahyal musculature. Incision in the median line. Exposure of the cricoid cartilage, exposure of the isthmus, this is relatively far cranial. Undermining of the isthmus using a clamp. Overall, the isthmus is very narrow, therefore coagulation in the median line and transection of the isthmus. Exposure of the anterior surface of the trachea and the tracheal clips. The brachiocephalic trunk can be palpated in depth. Now identify the area between the 2nd and 3rd cricoid cartilage. Enter with the scissors. Suture with 2 caudal and 2 cranial sutures. Skin suture with 2 stitches on the right and left. Then problem-free reintubation to an 8-gauge cannula and completion of the procedure without complications. Preoperative administration of 3 g Unacid. The patient goes to the intensive care unit intubated and ventilated. Please note the histology.