First of all, after intubation and preparation by the anesthesia colleagues, positioning of the patient. Inspection of the primary tumor region. An exophytic, exulcerated tumor is found in the area of the left edge of the tongue and the soft palate with involvement of the posterior floor of the mouth. Palpation reveals that the majority of the tumor is growing submucosally into the tongue. The tumor clearly extends beyond the midline in the area of the base of the tongue, but with sufficient residual distance to the opposite side. In addition, the tumor is clearly growing towards the floor of the mouth and cervically. Transoral tumor resection is therefore performed first. Removal of the soft palate section, taking the tonsil lobe with it, resection of the posterior floor of the mouth and resection of the exophytic tumor section up to the area of the edge of the tongue. This resection is completely covered with margin samples, which are diagnosed as tumor- and dysplasia-free in the frozen section diagnostics. Now continue the tumor resection from the transcervical side. Submandibular skin incision, separation of skin and subcutaneous tissue, dissection of the platysma. Exposure of the sternocleidomastoid muscle, exposure of the omohyoid muscle, exposure of the hardened submandibular gland and the digastric muscle. The tumor can be palpated under the submandibular gland with infiltration of the lateral floor of the mouth. Due to the depth, first expose the vessels. Evacuation of the anterior neck preparation with removal of the facial vein and preservation of the superior thyroid artery. Exposure of the carotid artery and the internal jugular vein of the vagus nerve in the area of the internal jugular vein Level II and III, several macroscopically clearly suspicious nodules can be seen, but these can be separated from the accessorius nerve. Removal of the metastases in toto. Cranial dissection, resection of the digastric muscle. Release of the submandibular gland while sparing the ramus marginalis mandibulae. Palpation shows the tumor infiltrating the floor of the mouth up to just before the hyoid, here moderately displaceable, therefore involving the left half of the hyoid. Cranial dissection along the carotid artery. Separation of the facial artery and lingual artery. The hypoglossal nerve also appears to be pulling into the tumor conglomerate and is removed. Now successive extension of the pharyngotomy over the tonsillar lobe and the lateral floor of the mouth, continuing over the pharyngeal side wall up to the level of the vallecula. Resection as described of the hyoid with attached external floor of mouth muscles. Resection of the tumor within the tongue, leaving a muscle cuff on the tumor so that the final tumor can be resected macroscopically in sano; only at one point was there a muscle tear above the tumor capsule during dissection, which is marked. An extensive resection is performed to cover this area. Covering of the tumor in the marginal area and in the previously described muscular part with marginal samples, these are also diagnosed as tumor-free and dysplasia-free, so that a R0 situation can finally be assumed. Measurement of the defect. At the same time, the right-sided neck dissection was performed and the antero-lateral thigh graft was lifted to perform the neck dissection. A submandibular skin incision is also made here. Cutting through skin and subcutaneous tissue. Separation of the platysma. Dissection. Exposure of the sternocleidomastoid muscle and the omohyoid muscle. Exposure of the submandibular gland and digastric muscle. Release of the anterior neck preparation with careful protection of the hypoglossal nerve and the superior thyroid artery as well as the facial vein. Free preparation of the internal jugular vein. Exposure and preservation of the accessory nerve, evacuation of the accessory triangle and level V with careful protection of the cervical plexus branches. Final wound inspection and wound irrigation and, if the wound is dry, insertion of a 10-gauge Redon drain and careful two-layer wound closure. To elevate the antero-lateral thigh graft after doppler sonographic identification of a main perforator and three secondary perforators, the graft measuring a total of 15 x 10 cm with soft palate and tongue base configuration is indicated. Medial incision. Cut through skin and subcutaneous tissue. Exposure of the rectus femoris muscle. Strictly subfascial dissection. Identification of the pedicle vessel, which runs relatively cranially. The ramus descendens is relatively weak. Identification of the fasciocutaneous perforator, the secondary perforators run intramuscularly, complete resection of the graft. Partial entrainment of the fascia lata. Inclusion of a sufficient muscle cuff. Isolation to the pedicle vessel. Isolation on the artery and vein and, if the blood supply to the graft is normal, removal of the graft. Subsequent careful hemostasis. Insertion of a 10-gauge Redon drain and careful two-layer wound closure and adaptation of the skin edges. Subsequent successive insertion of the graft, primarily via the tanscervical area. Overall very good fit. Reconstruction of the entire tongue and reconstruction of the largely resected base of the tongue with good volume filling. Transoral completion in the area of the soft palate and floor of the mouth. Overall intact conditions on all sides. Cervical anastomosis conditions significantly more difficult due to the position of the anastomosis and the now somewhat obstructive muscle cuff. Conditioning of the detached lingual artery, arterial anastomosis performed with 8-0 Ethilon with good flow under markedly difficult suturing conditions with pronounced arteriosclerosis in the area of the graft vessel. Overall, however, intact anastomosis with immediate regular venous return. Conditioning of the facial vein in the stump area. Sizing of a coupler size 3.5 and insertion of the venous anastomosis without any problems using the coupler system. Subsequent regular graft perfusion. The muscle cuff can now be well integrated into the neck, resulting in a good position of the anastomosis, but also complete filling of the neck. Therefore, a caudal rubber flap is inserted later. Careful two-layer wound closure. Finally, the tracheotomy is performed. In this case, post-tracheotomy at the beginning of the year. Opening of the skin scar, cutting of scars. Exposure of the anterior surface of the trachea. Reopening of the trachea in the former area between the 1st and 2nd tracheal ring, followed by insertion of the muco-cutaneous anastomosis and problem-free reintubation onto a size 8 low cuff cannula, which is suture-fixed. The procedure was then completed with a vital graft. Conclusion: Intraoperative R0 resected cT4a cN2b tongue margin and tongue base carcinoma on the left. If the graft heals properly, the first attempts at swallowing can be started from the 8th postoperative day. Left cervical swelling due to the clear muscle cuff, please consult the surgeons before manipulation. Due to the extent of the tumor, adjuvant RCT appears to be urgently required.  