Total cT3 tumor. Midline of the tongue reached, but not crossed. Repeated pharyngoscopy and laryngoscopy as well as oral cavity inspection: confirmation of tumor extension. Correspondingly, another CT assessment. PEG placement is now performed first: insertion with the esophagoscope through the esophagus into the stomach. After establishing spontaneous diaphanoscopy, insertion of a 15 mm abdominal wall tube without any problems. Fixation to the abdominal wall. Then tumor resection: Start with transoral resection: visualization of the tumor. The tumor is incised macroscopically and palpated on all sides with a safety margin of at least 1-1.5 cm. The posterior 2/3 of the tongue is removed up to above the midline, in the tongue base area about half of the tongue base is removed. In the floor of the mouth, removal of all soft tissue up to the lower jaw including the lingual nerve. Glossoalveolar groove and tonsil are resected together with parts of the pharyngeal side wall, caudal to it. As the overview of the soft tissue extension dorso-caudally below the mandible is not quite sufficient, the decision was made to complete the resection from transcervical to neck dissection. Therefore, repositioning to complete the tumor resection and neck dissection on both sides. Injection of 10 ml Ultracaine 1% with adrenaline into each side of the neck. Marking of the required tracheostomy. Start with neck dissection on the left: Skin incision in typical manner. Exposure of the sternocleidomastoid muscle. Exposure of digastric muscle, omohyoid muscle and infrahoyidal muscles. Exposure of the submandibular gland, which is initially left in place. Evacuation of level II-V. Internal carotid artery, external carotid artery, internal jugular vein, facial vein and external jugular vein are exposed and preserved. The accessorius, hypoglossal and vagus nerves and the branches of the cervical plexus are also preserved. This results in a level II to V neck dissection. Subsequent completion of the tumor resection. For this purpose, the digastric and styloid muscles are severed. Dissection of the submandibular gland. This is removed with all attached soft tissue en bloc with the soft tissue in connection with the inner tumor preparation and pulled through transorally. The tumor preparation is thread-marked and sent for frozen section. All tumor margins free in the specimen. In the dorso-basal area at the transition from the body of the tongue to the base of the tongue, removal of the tumor bordering on the resection margins, therefore another slice of soft tissue is removed from this area, which is then sent for final diagnosis. Overall R0 situation. This is followed by neck dissection on the right side: This is performed by A. Dittberner. Evacuation of levels II to IV in a typical manner with exposure of the internal carotid artery, external carotid artery, superior thyroid artery. V. jugularis interna, externa. V. jugularis cannot be preserved due to a tear and is ligated. Exposure of the vagus nerve, hypoglossal nerve and accessorius nerve as well as the branches of the cervical plexus, all structures are preserved. This results in evacuation of levels II to IV. Cranially, the submandibular gland is exposed and preserved. Subsequent tracheostoma creation: small Kocher collar incision, exposure of subcutaneous tissue, platysma. Dissection through the infrahyoid muscles after spreading them in the linea alba. Exposure of the thyroid isthmus. This is passed underneath, clamped off, severed and supplied by means of puncture ligatures. Exposure of the trachea. Creation of a broadly pedicled Björk flap. This is epithelized in the typical manner. Re-intubation and insertion of a laryngectomy tube. Subsequent irrigation of all wound areas with hydrogen and Ringer's solution. Removal of the forearm flap: measurement of the demissions results in a flap length of 11-12 cm and a width of up to 7 cm. The flap is marked on the forearm in the required size and shape. First cut around the flap from the ulnar side. Extension of the incision into the crook of the elbow. Depiction of the superficial venous system. Incision of the flap from the radial side. Lifting of the flap from ulnar and radial subfascial. Distal clamping of the radial artery. Exposure of the pedicle with the radial artery and radial vein. Dissection up to the olecranon. Exposure of the connection between the superficial and deep venous system. Two outlets from the area of the cephalic vein can be visualized. An acceptable confluence in the area of the radial vein. The radial artery is then removed. This is treated with puncture ligatures 4-0 Prolene. Lift the flap subfascially along the pedicle, smaller branches are coagulated or glued bipolarly. Dissection up to the antecubital fossa. The interosseous artery is clamped for 10 minutes. Here too, as before clamping the radial artery, constant saturation above 100 %. Disconnect the interosseous artery. Then remove the flap. The brachial artery is treated with 6-0 Vascufil sutures. Here too, saturation at 100 %. The veins are clamped and ligated. Flap is removed and flushed with heparin solution. After careful hemostasis, the proximal part of the forearm is closed in layers. The forearm defect is covered with thick split skin 0.7-0.8 mm. For this purpose, split skin is removed from the right thigh with the dermatome. Suture the split skin into the forearm defect. Thigh is treated with hydrogel dressing. The forearm is treated with ..............-Mepilex dressing, with a loose swab dressing on top, which is modeled using absorbent cotton. Fitting of a cramp splint. This is loosely fixed with a tape bandage. Positioning of the arm. Subsequent suturing of the radial flap into the defect: After partial suturing, the flap is gradually worked into the defect. Tension-free suturing of the flap is achieved. The stem is inserted through the large tunnel into the soft tissues of the neck. Complete tension-free defect coverage. Vessels are conditioned. The radial artery is sutured to the superior thyroid artery after conditioning. For this purpose, fish-mouth-like dilation of the superior thyroid artery. Suture with Ethilon 9-0 sutures. After opening the previously inserted clamps, good arterial flow, good venous return. Both outlets of the cephalic vein are conditioned for the anastomosis. One outlet is anastomosed with an outlet from the facial vein after conditioning using a 2.5 mm coupler. After opening the clamp, there is no venous return. Positive smear phenomenon. The other outlet from the cephalic vein is anastomosed after conditioning with the external jugular vein using a 3.5 mm coupler. Here too, after opening the clamp, reflux without any problems, positive smear phenomenon. Subsequent clipping of the still open confluence. Irrigation of the entire neck area and careful hemostasis. Layered wound closure on the right with insertion of a Redon drain. Layered wound closure on the left with insertion of 2 flaps. Insertion of a tracheostomy tube, which is fixed with sutures. Tracheal cannula with size 8. Repeated inspection of the flap. This is vital. Completion of the procedure without complications. Patient has received Unacid several times intraoperatively. Please continue this antibiotic treatment for one week. Patient goes to intensive care unit for monitoring. Please elevate the patient's upper body. Flap control according to the scheme, clinically if necessary also with Doppler sonography control. Continue heparin which was started intraoperatively at 500 E/h for 5 days. Nutrition via the PEG tube. After 7-10 days, if necessary, swallow porridge and then build up diet. Post-ventilation for one night. Overall cT3 oral floor oropharyngeal carcinoma on the left. Lymph node status in any case cN2b, possibly also cN2c on the right with some enlarged lymph nodes. Further procedure after final histology, presentation at the interdisciplinary tumor conference.