577. OUTCOMES OF SIMULTANEOUS RESECTION AND RECONSTRUCTION OF ESOPHAGEAL SQUAMOUS CELL CARCINOMA SYNCHRONOUSLY ASSOCIATED WITH HEAD AND NECK CANCER

Abstract In 1953, a study by Slaughter et al. on oral cancer proposed that field cancerization is the phenomenon of widespread carcinogenesis across multiple regions due to long-term exposure to common cancer-causing factors. Esophageal squamous cell carcinoma (ESCC) and head and neck cancer (HNC) share common risks, such as smoking and alcohol consumption, and are often observed synchronously. Therefore, treatment strategies based on tumor stages are important. In our hospital, for synchronous HNC and thoracic ESCC, local resection is indicated if the HNC is ≤T2, and resection with reconstruction is indicated if the HNC is ≥T3, and a one-stage operation for thoracic ESCC and HNC was generally performed. Here, we examined treatment strategies based on the results of simultaneous resection and reconstruction of synchronous thoracic ESCC and HNC in our hospital. A total of 174 patients with esophageal cancer underwent surgery at our hospital between January 2008 and December 2023. Among them, 16 (9%) had 18 lesions of synchronous HNC and nine patients (5%) underwent simultaneous resection and reconstruction. Patients with thoracic ESCC had Ut/Mt/Lt; 1/6/2; T-factor, T1/2/3; 5/2/2; N-factor, N0/1:6/3; and clinical stage, stage I/II; 2/6. For synchronous HNC, hypopharyngeal/oropharyngeal/laryngeal/cervical esophageal cancer; 5/2/1/2; T factor was T2/3/4; 1/6/3; N factor was N0/1/2c/3a/3b; 4/2/2/2/1/1; and clinical stage was stage II/III/IV; 1/5/4. Six patients underwent surgery after preoperative chemotherapy or chemoradiotherapy. Total pharyngo-laryngo-esophagectomy (TPLE) was performed using a thoracoscopic transthoracic approach in six patients, transhiatal approach in two, and mediastinoscopic approach in one. Regarding reconstruction, a gastric tube was used in nine patients, including eight patients in whom it was interposed with the free jejunal autograft. The median operative time was 929 min (590–1248 min) and median blood loss was 622 mL (213–1764 mL). Only patients with skin valve necrosis underwent reoperation; however, there were no hospital deaths, and the median postoperative hospital stay was 39 days (28–59 days). Recurrence was observed in four cases. All cases were considered to be due to HNC, and three were stage IV cases with advanced lymph node metastasis. Simultaneous resection and reconstruction for synchronous HNC and the thoracic esophagus is a highly invasive treatment that can be performed safely. Recurrence has been observed in advanced cases of HNC, and further development of multidisciplinary treatment, including preoperative chemotherapy, is necessary.