336 Background: Esophageal cancer treatment, especially esophagectomy, is highly invasive, so treatment strategies are considered in view of existing double cancers. On the other hand, in Japan, 90% of esophageal cancers are squamous cell carcinoma, and it is known that there are a large proportion of head and neck cancers for double cancers as field cancerization. Methods: The aim of this study is to investigate the types of double cancer, simultaneous/metachronous, and the frequency and treatment policy of head and neck cancer as a particularly high coexistence rate for esophageal cancer surgery patient. The subjects were 304 patients who underwent esophagectomy performed from April 2010 to December 2017. All patients were examined with high-definition endoscopy with NBI by certificated endoscopist at the first visit as a search for simultaneous double cancer from the pharynx to the stomach. And after esophagectomy, endoscopy was also performed to check for metachronous double cancers in the remaining esophagus, gastric tube, and pharynx at least every 2 years. Results: The number of double cancer cases was found in 94 cases (30.9%), and the total number of double cancer cases was 122. Head and neck cancer(33 cases), stomach cancer(16 cases), and colon cancer(12 cases) were observed as the main course of double cancers. In double cancer cases, 47cases(50.0%) were metachronous, 35cases(37.2%) were simultaneous, and 12cases(12.8%) were both synchronous. The most common double cancer was head and neck cancer(33 cases:35.1%), and 23 cases were simultaneous, 10 cases were metachronous. As treatment strategy for head and neck cancer, endoscopic laryngo-pharyngo surgery(ELPS) were 19 cases. 10 cases(52.7%) were synchronous cancers, and 9 cases (47.3%) were metachronous cancers which were detected during follow-up after esophagectomy. Conclusions: Head and neck cancer associated with esophageal cancer surgery is the most common type of double cancer, and 1/3 of ELPS cases have been detected by follow-up endoscopy after esophagectomy, so endoscopic surveillance was also considered important.
Current Status of Double Cancer and Its Countermeasures. Present Status and Management of Multiple Primary Esophageal Cancer Associated with Head and Neck Cancer.
