390 STRATEGY FOR TREATMENT OF EARLY ADENOCARCINOMA (T1) OF THE ESOPHAGOGASTRIC JUNCTION ACCORDING TO LYMPH NODE METASTASIS STATUS AND VASCULAR INVASION

Incidence of adenocarcinoma of the esophagogastric junction is increasing in Japan. However, in early cases (T1), there is no consensus on treatment strategy. The purpose of this study was to determine the optimal range of resection and lymph node dissection according to lymph node metastasis status and vascular invasion in early adenocarcinoma (T1) of the esophagogastric junction. Methods We investigated patient characteristics, surgical procedures, recurrence pattern, and optimum extent of lymph node dissection in 22 patients who underwent surgery in our hospital from 2000 to 2016 and were diagnosed with early adenocarcinoma of the esophagogastric junction (by Nishi’s classification). Results Four patients with lymph node metastasis, the depth of invasion was sm2 and lymphatic invasion was positive (ly1–ly3, focal lymphatic invasion to prominent lymphatic invasion). In all cases, the site of lymph node metastasis was the lesser gastric curvature. None of the patients developed postoperative lymph node recurrence. An examination of the outcomes revealed that the metastases were hematogenous in all patients with a depth of invasion of sm2 and a positive venous invasion (v1, focal vascular invasion). Conclusion We conclude that transhiatal esophagectomy should be selected as a minimal requirement, and that dissection of the abdominal lymph node (particularly on the lesser curvature side of the superior part of the stomach) is sufficient, for patients with early adenocarcinoma of the esophagogastric junction. In cases where the depth of invasion is sm2 or greater and vascular invasion is present, patients may require adjuvant therapy regardless of lymph node metastasis status.

State of the Art: Management of Barrett’s Esophagus Related Dysplasia and Neoplasia—Which Patient and What Therapy?

Endoscopic eradication therapy (EET) is safe and effective in the management of Barrett’s esophagus (BE) related dysplasia and early adenocarcinoma. EET includes endoscopic resection of the visible lesions followed by ablation to eradicate the residual Barrett’s epithelium. Techniques available for endoscopic resection include cap-based endoscopic mucosal resection and endoscopic submucosal dissection. Ablative therapies such as RFA, cryoablation and APC are used for the eradication of dysplastic BE and to prevent progression to EAC. Complete remission of intestinal metaplasia is the goal of EET. Post-treatment endoscopic surveillance is recommended to detect recurrence of metaplasia/dysplasia, mostly at the gastroesophageal junction.

Confocal Laser Endomicroscopy vs Biopsies in the Assessment of Persistent or Recurrent Intestinal Metaplasia/Neoplasia after Endoscopic Treatment of Barrett’s Esophagus related Neoplasia

Background and Aims: Patients after endoscopic treatment of Barrett‘s esophagus (BE) related neoplasia (BORN) should enter endoscopic surveillance with biopsies to detect persistent or recurrent neoplasia or intestinal metaplasia (IM). Probe-based confocal laser endomicroscopy (pCLE) serves as a virtual biopsy and could replace standard biopsies. However, the role of pCLE in patients after endoscopic treatment of BORN has not been systematically assessed. The aim of this study was to compare pCLE with biopsies in detecting persistent/recurrent IM/neoplasia. Methods: A single center, prospective and pathologist-blinded study was performed. Patients after endoscopic treatment of BORN (endoscopic resection or dissection, radiofrequency ablation) underwent surveillance endoscopy with pCLE followed by biopsies. Results: A total of 56 patients were enrolled: initial diagnoses were low-grade dysplasia (LGD) in 24 patients (43%), high-grade dysplasia (HGD) in 12 patients (21%) and early adenocarcinoma (EAC) in 20 patients (36%). Only one patient (2%) experienced recurrent neoplasia (LGD), which was diagnosed by pCLE only. Twenty patients (35.7%) experienced persistent/recurrent IM, diagnosed by both pCLE and biopsies in 17 patients (17/30, 85%) and by pCLE only in 3 pts (3/30, 15%). Sensitivity, specificity, positive and negative predictive values to diagnose recurrent/persistent IM did not differ significantly between pCLE and biopsies; diagnostic accuracy was 100% (95%CI 93.6-100) for pCLE and 94.6 (95%CI 85.1-98.9%) for biopsies, p=0.25. In patients with IM detected by both tested methods, pCLE detected significantly more goblet cells (median 43 per patient) than biopsies (median 12 per patient), p=0.01. Conclusion: pCLE is at least as effective as standard biopsies in the detection of persistent/recurrent IM after endoscopic treatment of BORN.

Detection of Early Adenocarcinoma of the Esophagogastric Junction by Spraying an Enzyme-Activatable Fluorescent Probe Targeting Dipeptidyl Peptidase-IV

Background: It is still difficult to detect and diagnose early adenocarcinoma of the esophagogastric junction (EGJ) using conventional endoscopy or image-enhanced endoscopy. A glutamylprolyl hydroxymethyl rhodamine green (EP-HMRG) fluorescent probe that can be enzymatically activated to become fluorescent after the cleavage of a dipeptidyl peptidase (DPP)-IV-specific sequence has been developed and is reported to be useful for the detection of squamous cell carcinoma of the head and neck, and esophagus; however, there is a lack of studies that focuses on detecting EGJ adenocarcinoma by fluorescence molecular imaging. Therefore, we investigated the visualization of early EGJ adenocarcinoma by applying EP-HMRG and using clinical samples resected by endoscopic submucosal dissection (ESD). Methods: Fluorescence imaging with EP-HMRG was performed in 21 clinical samples resected by ESD, and the fluorescence intensity of the tumor and non-tumor regions of interest was prospectively measured. Immunohistochemistry was also performed to determine the expression of DPP-IV. Results: Fluorescence imaging of the clinical samples showed that the tumor lesions were visualized within a few minutes after the application of EP-HMRG, with a sensitivity, specificity, and accuracy of 85.7%, 85.7%, and 85.7%, respectively. However, tumors with a background of intestinal metaplasia did not have a sufficient contrast-to-background ratio since complete intestinal metaplasia also expresses DPP-IV. Immunohistochemistry measurements revealed that all fluorescent tumor lesions expressed DPP-IV. Conclusions: Fluorescence imaging with EP-HMRG could be useful for the detection of early EGJ adenocarcinoma lesions that do not have a background of intestinal metaplasia.