After appropriate preparation, first perform a diagnostic hypopharyngoscopy. There is no macroscopic evidence of a tumor, so several tissue samples are taken. From these, the PE from the piriform sinus is found to be infiltrated by tumor. Start of surgery after appropriate preparation. After sharp transection of the cutis, the subcutaneous cutis and the platysma as well as the subcutaneous fatty tissue and the platysma, the large metastasis is exposed. Exposure of the vascular nerve sheath caudally and ligation of the internal jugular vein. Dissection of the sternocleidomstoideus muscle caudally. Expose the digastric muscle starting at the posterior abdomen. From there, follow ventrally to the omohyodeus muscle. Locate and ligate the internal jugular vein cranially under the digastric muscle. Then dissect the common carotid artery starting from caudal to cranial. Contrary to the radiological report, the carotid artery is not infiltrated. Therefore, the bifurcation together with the internal and external carotid artery can be dissected away from the metastasis in a healthy layer. Exposure and preservation of the hypoglossal nerve on the left side until the end. The sternocleidomastoid muscle is then removed together with the cranial accessorius nerve. The metastasis is then mobilized laterally, including resection of the cervical plexus and parts of the underlying musculature. The phrenic nerve is exposed and spared until the end. However, the vagus nerve runs through the metastasis and is separated from it caudally and cranially. The large metastasis is then resected with the surrounding fatty tissue in the form of a radical neck dissection. Metastases extend caudally to the clavicle. It is assumed that the thoracic duct is also injured here. The surrounding connective tissue is therefore grasped and ligated. In addition, the caudal stump of the sternocleidomastoid muscle is further exposed and sutured onto the suspected defect site. The upper horn of the thyroid cartilage and the lateral part of the hyoid bone are then exposed. Complete mobilization of the hypoglossal nerve, which is turned upwards. Separation of the digastric muscle. Exposing the hypopharyngeal side wall and performing the lateral pharyngotomy. Enter the pharynx at approximately the level of the upper edge of the epiglottis. From there, the tumor is explored in the direction of the piriform sinus. This is about the size of a pea and is hard to the touch. Triggering of the piriform sinus so that the tumor can be successively excised under vision. The resection covers the entire piriform sinus on the left side and extends to the arytenoid cartilage on the left side. The specimen is then mounted on a cork plate with corresponding markings. The frozen section histology shows that there is still some CIS in the area of the medial margin, i.e. towards the posterior wall of the hypopharynx. Therefore, a resection is performed at this site and another frozen section is made at the margin, which then proves to be free of tumor and CIS. The defect measures approximately 5 1/2 x 5 cm, so that the corresponding radial lobe of <CLINICIAN_NAME> is elevated. Elevation of the radial forearm flap on the left (<CLINICIAN_NAME>/PJ): Palpatory identification of the distal radial artery. Marking of the flap borders (6 x 4 cm) on the distal forearm, proximal to the flexor retinaculum, with an S-shaped incision running proximally into the cubital fossa. Incision of cutaneous and subcutaneous tissue starting proximally. Identification and visualization of the venous confluence in the cubital fossa. Identification of the cephalic vein and dissection of the vein distally with integration into the radial graft margin. Identification of the ramus externus of the radial nerve and elevation of the radial portion, leaving the peritendineum of the tendons of the brachioradialis muscle intact. Subsequent ulnar incision down to the forearm fascia. Incision of the fascia and subsequent subfascial elevation of the ulnar edge of the graft up to the tendon of the flexor carpi radialis muscle. Care is taken to leave the peritendineum on the flexor tendons and to spare the ulnar artery. Identification of the distal radial artery and trial clamping with a vascular clamp. After 5 minutes with good oxygen saturation measured by pulse oximetry (measured on the index finger), the vessels are removed with subsequent ligation (Prolene 6.0). Successive detachment of the flap pedicle from the M. pronator quadratus and M. flexor pollicis longus with ligation of the outgoing perforators using a vessel clip into the cubital fossa. Exposure and protection of the radial nerve on the medial side of the brachioradialis muscle. Exposure of the brachial artery, V. mediana cubiti, A. ulnaris. First removal of the radial artery, then of two veins of the superficial venous system. Vascular ligation by means of a bypass ligature (artery) and vascular clip (veins). Subtle hemostasis in the area of the wound bed using bipolar coagulation forceps. Two-layer wound closure in the area of the proximal forearm. Defect coverage of the graft bed with split skin from the right thigh in the usual manner. Suturing of preparation swabs. Application of a wound dressing and a forearm splint. Completion of graft elevation without complications. PEG placement (<CLINICIAN_NAME>/<CLINICIAN_NAME>): Entering with the gastroesophagoscope under air insufflation, pre-scanning into the stomach. After spontaneous diaphanoscopy, insertion of a PEG in the typical manner using the thread pull-through method. Neck dissection is then performed on the right side. All non-lymphatic structures in regions II to V are removed while sparing them. The facial artery is then traced up to the lower jaw and deposited there so that it can be used for subsequent anastomosis. A breakthrough is then created via the supralaryngeal muscles to the opposite side for insertion of the flap pedicle. After lifting the radial flap, it is sutured into the hypopharyngeal defect. The pedicle is then passed over the entire transition to the opposite side and arterially connected to the facial artery there. The venous anastomosis is made with 2 veins to the internal jugular vein. The lifting defect is then treated with split skin from the right thigh of <CLINICIAN_NAME>. Subsequently reintubation onto an 8 . cannula. Complete wound closure after insertion of Redon drains and 2 drainage flaps in the neck. End of the operation, transfer of the patient to anesthesia. Conclusion: Resection of a small piriform sinus carcinoma on the left side via lateral pharyngectomy with a large metastasis on the left side. Contrary to the radiological findings, the common carotid artery was not infiltrated by the tumor. Radical neck dissection on the left side and selective neck dissection on the right side. Defect coverage with radial lobe graft from the left forearm. Due to the extensive metastasis, adjuvant radiochemotherapy is recommended.