After appropriate preparation, the PEG tube is first inserted: PEG insertion using the thread pull-through method in the usual manner. With good diaphanoscopy, this could be done without any problems. Then, after sterile washing and draping and removal of the arm, the tracheostomy is started. After a transverse skin incision, the remaining prelaryngeal musculature is pushed apart and the trachea is exposed on the pretracheal lamina. The remaining rudimentary isthmus is then clamped, cut and stitched. The tracheostomy is then performed between the 2nd and 3rd tracheal clasp and the patient is reintubated without difficulty after completion of the mucocutaneous anastomosis. The operation then begins by opening the neck on the left side. The subcutaneous tissue and the platysma are cut sharply after a skin incision. Identification of the front edge of the sternocleidomastoid muscle and exposure of the vascular nerve sheath. The regions I to V are then evacuated, preserving all non-lymphatic structures. The superior thyroid artery, which is very small in caliber, is then skeletonized. The lingual artery and the facial artery are then dissected up to the mandible, separated and cut caudally for subsequent anastomosis. After identification of the ramus marginalis mandibulae, the periosteum of the mandible is sharply incised on the underside of the mandible and dissected enorally with the rasparatorium. The submandibular gland remains on the later resection specimen and is only exposed laterally, dorsally and ventrally. Subsequently, transition to transoral tumor resection. This is significantly limited due to the restricted mouth opening. The tumor extends to the left into the anterior floor of the mouth and also occupies the lateral third of the tongue. Palpatorily, it extends further back towards the base of the tongue almost to the midline. Therefore, start resection at the front and in the area of the tongue body with sufficient palpatory safety distance using the ultrasonic knife. The periosteum of the mandible on the side is sharply incised about 3 mm below the row of teeth and pushed off with the rasparator. There is no macroscopic evidence of tumor infiltration. In this way, the tumor is gradually developed from the front. The resection extends almost beyond the midline in the area of the base of the tongue. Subsequent transition to the transcervical area. Here, the pharynx is opened cranial to the hyoid bone so that a direct view of the tumor and the base of the tongue can also be obtained from here. After appropriate mobilization of the tumour transorally, the tumour can finally be mobilized cervically and finally removed with an appropriate muscle cuff. It is particularly difficult to remove a tumor extension that extends far caudally and medially, but which is ultimately included in the specimen. After removal of the specimen, it is marked accordingly. Removal of marginal sections in the area of the base of the tongue and the body of the tongue from the specimen itself and from all marginal areas. These are all found to be tumor-free. The frozen section taken in pathology from the lateral gingival area is also tumor-free. Basally, the frozen section pathological examination shows that the tumor is in toto, but with a distance of about 0.2 mm. Therefore, an appropriate resection is performed at this point basally without macroscopic evidence of further tumor parts. Ultimately, an R0 resection can be assumed. Subsequently, a 6 x 10 cm radialis graft is removed from the left forearm. Marking of the flap as well as the vessels and landmarks. Skin incision and dissection through the subcutaneous fatty tissue. Finding the cephalic vein and radial dissection of the cephalic vein. Now locate the confluence. Locate the bellies of the carpi radialis and brachioradialis muscles and successively dissect the muscle bellies until the pedicle is found. Undermination of the pedicle and tracing of the two superficial veins to above the crook of the elbow and snaring with a ligature. Now also dissect the radial artery up to the junction of the ulnar artery and ligate with one side. The flap is first incised on the ulnar side and dissected subfascially. Here the ulnar artery is very superficial, especially in the distal area it is exposed over a distance of 2 cm after detachment of the flap, but it can be completely spared. Smaller detachments are clipped. Now subfascial dissection of the ulnar side up to the flexor carpi radialis tendon. Now continue dissection from the radial side along the cephalic vein and also here clip various branches up to the distal side. Carefully elevate the cephalic vein with the overlying subcutaneous tissue as well as the flap and find the superficial ramus of the radial nerve and preserve it. A small branch extending into the flap is coagulated and cut. Suture the subcutaneous connective tissue to the radial and ulnar flap. The stalk, which is already exposed proximally, is now successively dissected and exposed distally. Locate the radial artery and snare it with a lateral suture. Lift the myofascial flap from the base so that it is only pedicled at the vessels. Now ligate the two veins and clip smaller venous branches and ligate the arteries laterally. Removal of the flap. Smaller bleedings are still pedicled bipolar. Lifting the split skin of the right lower leg and treating it. Sterile wound dressing. Suturing of the split skin in the usual manner and two-layer wound closure. Performing pie crusts. Application of octeniline and a plaster cast. Neck dissection is performed on the right side in regions I to V, preserving all non-lymphatic structures. The graft is then inserted into the defect and sutured into the defect first transorally and then transcervically. Suturing to the remaining gingiva, which is around 2 to 3 mm wide in the area of the lateral mandible, is extremely difficult. Prior to this, the bone was completely ground down with the drill, even if there was no macroscopic evidence of bone infiltration. After transoral fixation of the flap, the final adaptation is performed at the incision edges in the area of the lateral pharyngeal wall through the transcervical approach. This is followed by arterial anastomosis to the facial artery and 2 end-to-side anastomoses of the brachial veins to the internal jugular vein. Finally, defect coverage on the left forearm with split skin from the right thigh and appropriate wound dressings. Subsequently, insertion of a Redon suction drain on both sides and a flap in the area of the anastomosis with subsequent two-layer wound closure. Re-intubation of the patient onto an 8-gauge tracheostomy tube. Completion of the procedure and transfer of the patient to anesthesia. Conclusion: Transoral-transcervical resection of a large carcinoma of the floor of the mouth/basal tongue with defect coverage from the left forearm using a microvascularly anastomosed radial flap graft. Coverage on the left forearm with split skin from the right thigh. Additional tracheostomy and PEG placement. Intraoperative R0 resection after frozen section.