Surgical resection of the reconstructed gastric tube for GTC is invasive and is associated with high mortality  . ESD, which is a minimally invasive treatment for early gastric cancer, has an important role in the treatment of GTC. Some studies have already reported the long-term outcomes of ESD for GTC    . However, all of them were designed based on a retrospective survey at a single center. Although a multicenter prospective study is desirable, it is important to collect clinical data from each institution, because GTC is not frequently encountered. Our clinical data included a comparative number of cases (31 patients and 45 lesions) and comparatively long follow-up (median, 50 months). Therefore, these results can be considered valuable.
Some lesions that were not indicated for ESD according to the Japanese gastric cancer guidelines  were included in this study because of their surgical complications. This study found that the rate of complete ESD resections for GTC after esophagectomy was 86.7%. Lesions with incomplete resection included one lesion with a positive lateral margin and five lesions with positive vertical margins. The reason for the positive lateral margin was misdiagnosis of the tumor margin because of undifferentiated adenocarcinoma. The size of this lesion was larger than 40 mm; therefore, ESD was not indicated. We considered that several negative biopsy samples from outside the lesion should have been confirmed before ESD. This patient died of pancreatic cancer 30 months after ESD without GTC recurrence.
All five lesions with positive vertical margins had deep invasion to the SM or MP. The patient with invasion to the MP had local recurrence and died despite chemotherapy. One patient with invasion to the SM also had local recurrence and received additional radiation. Because the follow-up term after radiation was short in this case, remnant recurrence is possible. There have been no reports on the efficacy of chemotherapy or radiation for local recurrence of GTC after ESD. Although total reconstruction gastrectomy has been considered the standard treatment for local massive recurrence after ESD, surgery is not usually preferred because of the high risk of complications, such as leakage and pneumonia . Thoracoscopic and endoscopic cooperative surgery have been reported as minimally invasive , and the development of other surgical methods with less invasive techniques is expected for advanced GTC.
Only one patient died of GTC during this investigation. The disease-specific survival rate was more than 92.9%, which was considered a permissible level. However, 14 deaths due to other causes were confirmed, and the 5-year overall survival rate was 47.7%. Because patients were elderly (mean age, 73 years) and already had esophageal and gastric cancer, they were considered at high risk for other primary carcinomas. Moreover, they may have had respiratory and cardiovascular diseases due to smoking, diabetes mellites, or hyperlipidemia. Therefore, we should screen for other diseases before ESD and perform careful follow-up after ESD. ESD is less invasive than surgery for patients with GTC. Therefore, ESD should be considered the first choice if complete resection is possible.
Although ESD for GTC is safe and effective  , it is more difficult to resect lesions than early gastric cancer without reconstruction. The gastric tube has limited working space, food retention, and fluid pooling due to notable deformity of the stomach and severe fibrosis on the suture line after surgical reconstruction . Therefore, ESD for GTC should be performed by fully trained endoscopists. When there is a lesion on the suture line, severe fibrosis of the submucosal layer, and remaining surgical staples, attaching the ST hood short-type and traction methods, such as clipping with the line method, are effective for obtaining good endoscopic visualization   . When a lesion is submerged in fluid or blood, we should consider positioning the patient in the opposite direction. We consider ESD for GTC a safe treatment, because adverse events (delayed bleeding) occurred in only two cases. However, careful attention to distinctive complications, such as precordial skin burns after ESD in cases involving the retrosternal route, is required .
All patients had Helicobacter pylori-related atrophic gastritis. Because they were at high risk for gastric cancer, it is important to detect GTC during the early stage . Furthermore, we must stay aware of metachronous occurrences after curative ESD. Recent remarkable advances in magnifying endoscopy and narrow band imaging systems have allowed the development of early treatments for gastric carcinomas   . Careful observation is needed to manage worsening conditions in the gastric tube, such as deformity of the stomach, bleeding, and fluid pooling. The period from esophagectomy to GTC was 10.6 years in this study; therefore, regular long-term follow up is necessary.
This study had several limitations. First, our observations are based on an analysis of retrospective data from a single center; therefore, treatments were not based on any clear protocols. Second, the analysis was performed during a long period; therefore, the skill of the endoscopist who performed the diagnosis and ESD procedure for GTC gradually improved, which might have affected the results.