Esophageal carcinoma. Ex vivo endoluminal magnetic resonance imaging

Contribution of magnetic resonance imaging to the management of esophageal diseases: A systematic review

PURPOSE

Currently available imaging modalities used to investigate the esophagus are irradiating or limited to the analysis of the esophageal lumen. Magnetic resonance imaging (MRI) is a non-invasive and non-radiating imaging technique that provides high degrees of soft tissue contrast. Newly developed fast MRI sequences allow for both morphological and functional assessment of the esophageal body and esophagogastric junction. The purpose of this systematic review was to identify the contribution of MRI to the diagnosis and management of esophageal diseases, such as gastroesophageal reflux, esophageal motility disorders, esophageal neoplasms, and portal hypertension.

METHODS

We performed a systematic search of the Medline (via Ovid), EMBASE (via Ovid), PubMed and Cochrane Library databases from inception to December 2018 inclusively, using the MESH major terms "magnetic resonance imaging" AND "esophagus".

RESULTS

The initial search retrieved 310 references, of which 56 were found to be relevant for the study. References were analysed and classified in different subheadings: MRI protocols for the esophagus, gastroesophageal reflux disease, achalasia and other esophageal motility disorders, esophageal cancer, portal hypertension and other esophageal conditions.

CONCLUSION

MR Esophagography might become a non-invasive, non-irradiating technique of choice following diagnostic esophagogastroduodenoscopy for the assessment of esophageal diseases.

Newly developed surface coil for endoluminal MRI, depiction of pig gastric wall layers and vascular architecture in ex vivo study

BACKGROUND

The purpose of this study was to visualize the gastric wall layers and to depict the vascular architecture in vitro by using resected porcine stomachs studied with high-spatial resolution magnetic resonance (MR) imaging.

METHODS

Normal dissected porcine stomach samples (n = 4) were examined with a 3 Tesla MR system using a newly developed surface coil. MR images were obtained by the surface coil as receiver and a head coil as transmitter. High-spatial-resolution spin-echo MR images were obtained with a field of view of 8 x 8 cm, a matrix of 256 x 128 and slice thicknesses of 3 and 5 mm.

RESULTS

T1 and T2-weighted MR images clearly depicted the normal porcine gastric walls as consisting of four distinct layers. In addition, vascular architectures in proper muscle layers were also visualized, which were confirmed by histological examinations to correspond to blood vessels.

CONCLUSIONS

High-spatial-resolution MR imaging using a surface coil placed closely to the gastric wall enabled the differentiation of porcine gastric wall layers and the depiction of the blood vessels in proper muscle layer in this experimental study.

New coil concept for endoluminal MR imaging: initial results in staging of gastric carcinoma in correlation with histopathology

Our aim was to conduct a prospective study to evaluate staging accuracy of a new coil concept for endoluminal magnetic resonance imaging (MRI) on ex vivo gastric carcinomas. Twenty-eight consecutive patients referred to surgery with a clinically proven primary gastric malignancy were included. Surgical specimens were examined with a foldable and self-expanding loop coil (8-cm diameter) at 1.5 Tesla immediately after total gastrectomy. T1- and T2-weighted and opposed-phase sequences (axial, frontal sections; 3- to 4-mm slice thickness) were acquired. Investigators blinded to any patient information analyzed signal intensity of normal gastric wall, gastric tumor, and lymph nodes. Findings were compared with histopathological staging. On surgical specimens, 2-5 gastric wall layers could be visualized. All gastric tumors (26 carcinomas, two lymphomas) were identified on endoluminal MR data (100%). Overall accuracy for T staging was 75% (18/24); sensitivity to detect serosal involvement was 80% and specificity 89%. N staging correlated in 58% (14/24) with histopathology (N+ versus N-). The endoluminal coil concept is feasible and applicable for an ex vivo setting. Endoluminal MR data provided sufficient detail for gastric wall layer differentiation, and therefore, identification of T stages in gastric carcinoma is possible. Further investigations in in vivo settings should explore the potential of our coil concept for endoluminal MR imaging.

Esophageal cancer: a systematic review

Carcinoma of the esophagus has one of the lowest possibilities of cure, with 5-year survival rates estimated to be approximately 10% overall; these rates are second only to hepatobiliary and pancreatic cancers. This fact and the rapid increase in the incidence of adenocarcinomas of the esophagus in recent years challenges us to identify areas of improvement for all aspects of this disease. We discuss potential reasons for the increase in the incidence of adenocarcinomas, evidence that defines the similarity between tumors of the gastroesophageal junction and the tubular esophagus, and other prognostic factors that may influence future modifications of our staging classification of this disease. Surgical advances have translated into improvements in surgical morbidity and mortality rates. Current therapeutic options and the relative merits of the options are discussed. Improvements in patient outcome most likely hinge on earlier diagnosis, more accurate staging, and the optimal use of combined modalities, coupled with technical advances in the modalities. A systematic review approach was undertaken to evaluate the performance characteristics of newer staging tools and the value of different combined modality approaches with particular focus on the use of those approaches for patients with potentially curable disease. A similar methodologic approach was used to address the utility of the many strategies currently used in practice for the palliation of esophageal tumors, with particular focus on the relief of malignant dysphagia. Finally, a summary of published guidelines and population-based patterns of care are presented. This serves as an overview of how all of this evidence actually translates into the care we are providing. A coordinated international effort in population-based research and randomized controlled trials would be the cornerstone to future advances in this relatively uncommon but devastating disease.