Sergio Coda

Risk factors for cardiac and pyloric stenosis after endoscopic submucosal dissection, and efficacy of endoscopic balloon dilation treatment.

BACKGROUND AND STUDY AIMS Bleeding and perforation are major complications of endoscopic submucosal dissection (ESD) for early gastric cancer (EGC), but post-ESD stenosis represents a severe delayed complication that can result in clinical symptoms such as dysphagia and nausea. The aims of this study were to determine the risk factors and evaluate the clinical treatment for post-ESD stenosis. METHODS A total of 2011 EGCs resected by ESD at our institution between 2000 and 2005 were reviewed retrospectively. Resection was defined as cardiac when any mucosal defect was located in the squamocolumnar junction, and as pyloric when any mucosal defect was located < 1 cm from the pylorus ring. Post-ESD stenosis was defined when a standard endoscope could not be passed through the stenosis. We examined the incidence of post-ESD stenosis, its relationship with relevant factors, and the clinical course of post-ESD stenosis patients. RESULTS Post-ESD stenosis occurred with seven of 41 cardiac resections (17 %) and eight of 115 pyloric resections (7 %). Circumferential extent of the mucosal defect of > 3/4 and longitudinal extent > 5 cm were each significantly related to occurrence of post-ESD stenosis with both cardiac and pyloric resections. All 15 affected patients were successfully treated by endoscopic balloon dilation. CONCLUSIONS A circumferential extent of the mucosal defect of > 3/4 or longitudinal extent of > 5 cm in length were both demonstrated to be risk factors for post-ESD stenosis, in both cardiac and pyloric resections, and endoscopic balloon dilation was shown to be effective in treating post-ESD stenosis.

A Western single-center experience with endoscopic submucosal dissection for early gastrointestinal cancers

Endoscopic submucosal dissection (ESD) has gained worldwide acceptance as a treatment for early gastrointestinal cancers (EGICs). However, the management of these tumors in the Western world is still mainly surgical. Our aim was to evaluate the safety and feasibility of ESD at a European center. Based on the knowledge transferred by one of the most experienced Japanese institutions, we conducted a pilot study on 25 consecutive patients with EGICs located in the esophagus (n = 3), stomach (n = 7), duodenum (n = 1), and colon (n = 14) at our tertiary center over a 2-year-period. The main outcome measurements were complete (R0) resection, as well as en-bloc resection and the management of complications. The R0 and en-bloc resection rates were 100% and 84%, respectively. There were three cases of bleeding and five cases of perforation. With a median follow up of 18 months, two recurrences were observed. We conclude that ESD for early esophageal and gastric cancers is feasible and effective, while colonic ESD requires more expertise.

Fluorescence lifetime spectroscopy of tissue autofluorescence in normal and diseased colon measured ex vivo using a fiber-optic probe.

We present an ex vivo study of temporally and spectrally resolved autofluorescence in a total of 47 endoscopic excision biopsy/resection specimens from colon, using pulsed excitation laser sources operating at wavelengths of 375 nm and 435 nm. A paired analysis of normal and neoplastic (adenomatous polyp) tissue specimens obtained from the same patient yielded a significant difference in the mean spectrally averaged autofluorescence lifetime -570 ± 740 ps (p = 0.021, n = 12). We also investigated the fluorescence signature of non-neoplastic polyps (n = 6) and inflammatory bowel disease (n = 4) compared to normal tissue in a small number of specimens.

Endoscopic Mucosal Resection and Endoscopic Submucosal Dissection as Treatments for Early Gastrointestinal Cancers in Western Countries

Early gastrointestinal cancers are defined as lesions limited to the mucosa or submucosa without invading the muscularis propria, regardless of the presence of lymph node metastases. Although the natural history of these diseases is basically alike worldwide, its management is quite different between the East and West; aggressive surgery is frequently adopted by Western surgeons, while less invasive techniques are adopted by Asian colleagues. These techniques include endoscopic mucosal resection and endoscopic submucosal dissection which are now accepted as treatments for early gastrointestinal cancers in selected cases. Recent advances in endoscopic detection and treatment techniques, especially in Japan and Korea, have prompted Western endoscopists to learn these techniques. This review addresses recent advances regarding endoscopic resections of early gastrointestinal cancers, which promoted its use in Western countries. In addition, prospective studies on endoscopic resection in Western countries are also described.

In vivo measurements of diffuse reflectance and time-resolved autofluorescence emission spectra of basal cell carcinomas

We present a clinical investigation of diffuse reflectance and time-resolved autofluorescence spectra of skin cancer with an emphasis on basal cell carcinoma. A total of 25 patients were measured using a compact steady-state diffuse reflectance/fluorescence spectrometer and a fibre-optic-coupled multispectral time-resolved spectrofluorometer. Measurements were performed in vivo prior to surgical excision of the investigated region. Singular value decomposition was used to reduce the dimensionality of steady state diffuse reflectance and fluorescence spectra. Linear discriminant analysis was then applied to the measurements of basal cell carcinomas (BCCs) and used to predict the tissue disease state with a leave-one-out methodology. This approach was able to correctly diagnose 87% of the BCCs. With 445 nm excitation a decrease in the spectrally averaged fluorescence lifetime was observed between normal tissue and BCC lesions with a mean value of 886 ps. Furthermore, the fluorescence lifetime for BCCs was lower than that of the surrounding healthy tissue in all cases and statistical analysis of the data revealed that this decrease was significant (p = 0.002).

State of the art in advanced endoscopic imaging for the detection and evaluation of dysplasia and early cancer of the gastrointestinal tract.

Ideally, endoscopists should be able to detect, characterize, and confirm the nature of a lesion at the bedside, minimizing uncertainties and targeting biopsies and resections only where necessary. However, under conventional white-light inspection – at present, the sole established technique available to most of humanity – premalignant conditions and early cancers can frequently escape detection. In recent years, a range of innovative techniques have entered the endoscopic arena due to their ability to enhance the contrast of diseased tissue regions beyond what is inherently possible with standard white-light endoscopy equipment. The aim of this review is to provide an overview of the state-of-the-art advanced endoscopic imaging techniques available for clinical use that are impacting the way precancerous and neoplastic lesions of the gastrointestinal tract are currently detected and characterized at endoscopy. The basic instrumentation and the physics behind each method, followed by the most influential clinical experience, are described. High-definition endoscopy, with or without optical magnification, has contributed to higher detection rates compared with white-light endoscopy alone and has now replaced ordinary equipment in daily practice. Contrast-enhancement techniques, whether dye-based or computed, have been combined with white-light endoscopy to further improve its accuracy, but histology is still required to clarify the diagnosis. Optical microscopy techniques such as confocal laser endomicroscopy and endocytoscopy enable in vivo histology during endoscopy; however, although of invaluable assistance for tissue characterization, they have not yet made transition between research and clinical use. It is still unknown which approach or combination of techniques offers the best potential. The optimal method will entail the ability to survey wide areas of tissue in concert with the ability to obtain the degree of detailed information provided by microscopic techniques. In this respect, the challenging combination of autofluorescence imaging and confocal endomicroscopy seems promising, and further research is awaited.

Biophotonic endoscopy: a review of clinical research techniques for optical imaging and sensing of early gastrointestinal cancer

Detection, characterization, and staging constitute the fundamental elements in the endoscopic diagnosis of gastrointestinal diseases, but histology still remains the diagnostic gold standard. New developments in endoscopic techniques may challenge histopathology in the near future. An ideal endoscopic technique should combine a wide-field, “red flag” screening technique with an optical contrast or microscopy method for characterization and staging, all simultaneously available during the procedure. In theory, biophotonic advances have the potential to unite these elements to allow in vivo “optical biopsy.” These techniques may ultimately offer the potential to increase the rates of detection of high risk lesions and the ability to target biopsies and resections, and so reduce the need for biopsy, costs, and uncertainty for patients. However, their utility and sensitivity in clinical practice must be evaluated against those of conventional histopathology. This review describes some of the most recent applications of biophotonics in endoscopic optical imaging and metrology, along with their fundamental principles and the clinical experience that has been acquired in their deployment as tools for the endoscopist. Particular emphasis has been placed on translational label-free optical techniques, such as fluorescence spectroscopy, fluorescence lifetime imaging microscopy (FLIM), two-photon and multi-photon microscopy, second harmonic generation (SHG) and third harmonic generation (THG) imaging, optical coherence tomography (OCT), diffuse reflectance, Raman spectroscopy, and molecular imaging.

Anxiety, depression, hunger and body composition: III. Their relationships in obese patients

The present paper explores the relationships between anxiety, depression, hunger sensation and body composition in obese patients (OP). The aim is to detect whether or not there are abnormalities in these relationships in OP as compared to clinically healthy subjects (CHS). The study was performed on 22 CHS (2 M, 20 W; mean age=24±2 years; mean body mass index=21±2 kg/m2 and 48 OP (4 M, 44 W; mean age=40±17years; mean body mass index=32±7 kg/m2). Anxiety and depression were found to be correlated, negatively, with the relative lean body mass, and, positively, with the fat body mass in OP but not in CHS. These findings corroborate the idea that anxiety and depression can reach an abnormal expression when obesity shows its worst loss in lean body mass and its highest expansion in adipocyte mass. As hunger sensation was found not to correlate with either anxiety or depression in OP, the opinion is expressed that the impairment of anxio-depressive integrity is a corollary of obesity rather than a primary affective disorder leading to obesity via an enhanced food intake.

Complete Endoscopic Closure (Clipping) of a Large Esophageal Perforation After Pneumatic Dilation in a Patient with Achalasia

The risk of esophageal perforation following endoscopic balloon dilation for achalasia is in the range of 1%-5%, with a mortality rate of 1%-20%. Perforations need to be recognized early, and, if reasonable, an immediate endoscopic repair should be pursued quickly. Herein, we report a case of successful endoscopic closure by clipping of a large iatrogenic perforation in a patient with achalasia. An 80-year-old woman with achalasia was admitted to our institution to undergo pneumatic dilation. A 40-mm balloon dilator with inflation pressure of 20 psi was used for 2 minutes as usual. During the procedure, the patient had a transient bradycardia. Endoscopic control showed a 2-cm rupture of the distal esophagus. Prompt endoscopic repair of the perforation by endoclips (n=6) was then attempted, followed by conservative management by total parenteral nutrition and intravenous antibiotics. Endoscopic clipping completely closed the esophageal perforation. The patient was given oral nutrition 10 days later without any complications. Six months after discharge from the hospital, the patient was healthy and free of dysphagia. Endoscopy showed complete healing of the esophageal mucosa without luminal stenosis. This report highlights that prompt endoscopic clipping is a useful means to close a large esophageal perforation caused by pneumatic dilation.

Daily hunger sensation and body composition: I. Their relationships in clinically healthy subjects

The human hunger sensation (HS) is a perceptive signal characterized by day-night variability (DNV). This pattern was investigated with respect to its relations with the body compartments in 22 clinically healthy subjects (CHS, 11 males and 11 females mean age: 24±2.5 years, mean BMI: 21±1.7). The DNV was investigated by means of con ventional descriptive statistics and the single cosinor method (SCM). Both procedures were applied to the orexigram, i.e., the 24-h profile of the orectic stimulus (OS) provided by each subject, who self-rated his/her HS (from 1 to 10 hunger units) every half hour. Body composition was investigated by Bioelectrical Impedance Analysis (BIA) on the day when the orexigrams were compiled. It was found that the daily HS level correlates positively with the Free Fat Body Mass (FFBM) and negatively with the Fat Body Mass (FBM). These opposite relations indicate that HS is stimulated by the needs of the FFBM, and inhibited by expansion of the FBM, and provide further evidence of the existence of an “adipostat anorectic mechanism.