Towards personalized management of early esophageal adenocarcinoma.

PURPOSE OF REVIEW: This review aims to discuss recent advancements in the endoscopic management of early esophageal adenocarcinoma (T1 EAC). RECENT FINDINGS: Patients with high-risk EAC (defined by the presence of deep submucosal invasion, and/or lymphovascular invasion, and/or poor differentiation) have a higher risk of lymph node metastases than those with low-risk EAC. However, more recent, endoscopically-focused studies report a lower risk of lymph node metastases and distant metastases for high-risk EAC than previously assumed. Instead of referring all high-risk EAC patients for esophagectomy after a radical endoscopic resection, an alternative approach involving regular upper endoscopy with endoscopic ultrasound may allow for detection of intra-luminal recurrence and lymph node metastases at an early and potentially curable stage. SUMMARY: Endoscopic resection of mucosal and submucosal EAC might prove to be safe and curative for selected cases in the future, when followed by a strict follow-up protocol. Despite the promising results of preliminary studies, there is an ongoing need for personalized strategies and new risk stratification methods to decide on the best management for individual patients with high-risk T1 EAC.

Today's Mistakes and Tomorrow's Wisdom in the Management of T1b Barrett's Adenocarcinoma.

Background: Given the limitation that endoscopic resection only enables local intraluminal treatment without lymphadenectomy, the standard treatment of esophageal adenocarcinoma (EAC) with invasion of the submucosa (T1b) has long been surgical esophageal resection. However, in recent literature, the risk of lymph node metastases (LNM) associated with T1b EAC appears to be lower than previously assumed, and endoscopic management is increasingly being considered a valid and less invasive alternative to surgery. Summary: Surgical esophageal resection performed after radical endoscopic resection of T1b EAC often does not show any residual tumor or LNM in the resected specimen. Given the morbidity and mortality associated with surgical esophageal resection, endoscopic management with strict surveillance protocols has been more widely applied provided that the initial tumor was radically removed by endoscopic resection, reserving surgery for those cases where the additional risk of surgical esophageal resection is justified. These are the cases where intraluminal recurrent neoplasia is found that cannot be retreated endoscopically or cases with locoregional LNM detected during follow-up. In the future, selection of patients who can safely be managed endoscopically and those who may benefit from additional surgery after endoscopic resection of T1b EAC may become more tailored, using risk prediction calculators or sentinel node navigated surgery. Key Messages: Management of patients with T1b EAC is shifting from surgical treatment to less invasive endoscopic treatment strategies, including watchful waiting approaches. The risk of LNM of T1b EAC appears to be lower than long assumed. In the future, management of T1b EAC may become more individualized based on tools to predict LNM risk per patient case.

18F-FDG uptake in the colon is modulated by metformin but not associated with core body temperature and energy expenditure.

PURPOSE: Physiological colonic 18F-fluorodeoxyglucose (18F-FDG) uptake is a frequent finding on 18F-FDG positron emission tomography computed tomography (PET-CT). Interestingly, metformin, a glucose lowering drug associated with moderate weight loss, is also associated with an increased colonic 18F-FDG uptake. Consequently, increased colonic glucose use might partly explain the weight losing effect of metformin when this results in an increased energy expenditure and/or core body temperature. Therefore, we aimed to determine whether metformin modifies the metabolic activity of the colon by increasing glucose uptake. METHODS: In this open label, non-randomized, prospective mechanistic study, we included eight lean and eight overweight males. We measured colonic 18F-FDG uptake on PET-CT, energy expenditure and core body temperature before and after the use of metformin. The maximal colonic 18F-FDG uptake was measured in 5 separate segments (caecum, colon ascendens,-transversum,-descendens and sigmoid). RESULTS: The maximal colonic 18F-FDG uptake increased significantly in all separate segments after the use of metformin. There was no significant difference in energy expenditure or core body temperature after the use of metformin. There was no correlation between maximal colonic 18F-FDG uptake and energy expenditure or core body temperature. CONCLUSION: Metformin significantly increases colonic 18F-FDG uptake, but this increased uptake is not associated with an increase in energy expenditure or core body temperature. Although the colon might be an important site of the glucose plasma lowering actions of metformin, this mechanism of action does not explain directly any associated weight loss.