A Parallel Comparison Method of Early Gastric Cancer: The Light Transmission-Assisted Pathological Examination of Specimens of Endoscopic Submucosal Dissection

ObjectiveIt is always challenging to diagnose and characterize early gastric cancer surrounded by non-cancerous mucosa, including the malignant diagnosis and extent and depth of the lesions. Therefore, we developed a light transmission-assisted pathological examination to diagnose and characterize early gastric cancer. Here, we performed a parallel comparison between the light transmission-assisted pathological examination under endoscopy and the histological examination for the diagnosis of early gastric cancer.MethodsFirst, the endoscopic submucosal dissection (ESD) specimen was first placed on the surface of the light-emitting diode lamp to observe the mucosal surface structure and blood vessels. Second, the sliced and embedded tissue strips were cut into 3-µm sections for hematoxylin and eosin staining. Third, the histopathology of each section was projected onto a macroscopic image. Finally, the macroscopic and microscopic changes in the ESD specimens observed under endoscopy were compared. Seventy cases of early gastric adenocarcinoma were diagnosed and characterized using this new method.ResultsUsing the conventional pathological method, the demarcation line of the lesions was seen in 40 of 70 (57.1%) cases. Furthermore, no surface structure or microvascular changes were observed in any of the cases. Based on the light transmission-assisted pathological examination, 58 of 70 (82.9%) cases presented clear edges of neoplastic and non-neoplastic epithelia, with a classifiable surface structure (88.6%) and microvascular type (78.8%).ConclusionsThis pilot method provided a practical bridge between endoscopic and pathological examinations. Compared to the histological examination, the light transmission-assisted pathological examination was an easier and more precise way to match the in vivo endoscopic observation and in vitro pathological examination.

Adipose-derived Mesenchymal Stem Cells Improve the Healing of Tracheoesophageal Fistula in a Beagle Model

Background Tracheoesophageal fistula (TEF) is still a devastating clinical problem with high mortality. New clinical strategies were developed to sustain survival time. Mesenchymal stem cells were applied in many clinical wound healing fields. This study aims to investigate the main effect of stem cell to TEF.Material and Method We established a beagle model with TEF by punching the trachea and esophagus membrane and suturing. The beagles were divided into three groups (group 1 = 1, group 2 = 6, group 3 = 6). Group 2 and 3 received a TEF building operation. Group 3 were injected 2 ml stem cells (106 per animal), and group 2 injected saline water with same volume. Group 1 did not receive any intervention. All animals receipted total parental nutrition. The closure degree of fistula tissue was observed by bronchoscope and post-mortem after 35 d.Result Morphologic and histopathologic changes of fistulas were assessed by gross and endoscopic observation. The fistulas diameter was measured. In 35 d postoperatively, group 2 showed that 3 animals died for acute smother, 2 animal died for severe chronic pneumonia and 1 animal with consistent fistula. Group 3 showed that 2 animals fully closed, 3 animals fistula diameter significantly decreased, and 1 animal died for acute smother. In autopsy result, group 2 animals showed severer pneumonia degree than group 3 animals in 35 d.Conclusion The transplantation of stem cells can promote healing degree of TEF without any complications and relieve pneumonia at the same time.

Endoscopic Detection of Gastric Metastases in Skin Melanoma

Aim. A clinical description of disseminated skin melanoma with endoscopic observation of its pathognomonic pigmented metastases into the stomach.Key points. A 66-yo patient was hospitalised with dyspnoea, general weakness, cough and suspected community-acquired pneumonia. The patient had a complex examination, including computed tomography, which revealed a presumed malignancy of the right lung with secondary changes in the chest and abdominal organs. Esophagogastroduodenoscopy (EGDS) visualised multiple pigmented spots and raised black plaques in cardia and the gastric body diagnosed as a metastasising melanoma in stomach. Endoscopic verification of the metastases confirmed the correct diagnosis of primary skin melanoma.Conclusion. Metastatic melanoma of the gastrointestinal tract has non-specific symptoms and most often occurs during the dissemination process. Endoscopy should be used to correctly verify pigmented mucosal lesions, necessarily allowing for non-pigmented gastric neoplasms in patients with skin melanoma in history.

Recent Advances in Molecular Imaging of Colorectal Tumors

<b><i>Background:</i></b> Recent endoscopic studies have revealed that small colorectal tumors are often overlooked during colonoscopy, indicating that more sensitive detection methods are needed. <b><i>Summary:</i></b> Molecular imaging has received considerable attention as a new endoscopic technique with high sensitivity. It generally employs a fluorescence-labeled compound that specifically binds to a molecule on the tumor. Fluorescent probes for molecular imaging are largely classified as 2 types: a fluorescence-labeled antibody targeting a molecule specifically expressed on the tumor cell surface such as epidermal growth factor receptor or vascular endothelial growth factor (VEGF); and a fluorescence-labeled small molecule compound targeting a molecule specifically expressed in tumor cells including c-Met, glutathione S-transferase, γ-glutamyltranspeptidase, cathepsin, or endothelin A receptor. These probes successfully detected colorectal tumors in several animal studies. Moreover, 3 recent human clinical trials evaluating endoscopic molecular imaging for colorectal tumors have been reported. In one study, a Cy5-labeled synthetic peptide against c-Met was developed, and fluorescent endoscopic observation with this probe detected a greater number of colorectal adenomas than with white light observation. Another trial used IR800-labeled anti-VEGF antibody, which sensitively detected human colorectal adenomas by fluorescent endoscopy. Last, a fluorescent probe with synthetic peptide against BRAF-positive cells was able to visualize sessile serrated lesions. The fluorescent probes accumulated at very high levels in colorectal tumor cells but at lower levels in surrounding nonneoplastic mucosa. <b><i>Key Messages:</i></b> We expect that molecular imaging techniques with fluorescent probes will soon lead to the establishment of a highly sensitive endoscopic method for colorectal tumor detection.

Narrow band imaging under less-air condition improves the visibility of superficial esophageal squamous cell carcinoma

Background The current virtual chromoendoscopy equipment cannot completely detect superficial squamous cell carcinoma (SCC) in the esophagus, despite its development in the recent years. Thus, in this study, we aimed to elucidate the appropriate air volume during endoscopic observation to improve the visibility of esophageal SCC. Methods This retrospective study included a total of 101 flat type esophageal SCCs identified between April 2017 and January 2019 at the Department of Gastrointestinal Oncology, Osaka International Cancer Institute. Video images of narrow band imaging (NBI) under both less-air and standard-air conditions were recorded digitally. Videos were evaluated by five endoscopists. Relative visibility between less-air and standard-air conditions of the brownish area, brownish color change of the epithelium, and dilated intrapapillary capillary loop (IPCL) were graded as 5 (definitely better under less-air condition) to 1 (definitely worse under less-air condition), with 3 indicating average visibility (equivalent to standard-air observation). Results The mean (standard deviation) visibility score of the brownish area, brownish color change of the epithelium, and dilated IPCLs under less-air condition were 3.94 (0.58), 3.73 (0.57), and 4.13 (0.60), respectively, which were significantly better than that under standard-air condition (p < 0.0001). Esophageal SCC evaluated as ≥ 4 in the mean visibility score of the brownish area, brownish color change of the epithelium, and dilated IPCLs accounted for 50% (51/101 lesions), 34% (34/101 lesions), and 67% (68/101 lesions), respectively. Conclusions The present results suggested that NBI with less air might improve the visibility of flat type esophageal SCC compared with NBI with standard air. Less-air NBI observation may facilitate the detection of flat type esophageal SCC. Trial registration The present study is a non-intervention trial.