Improvement to ultrasonographical differential diagnosis of gastric lesions: The value of contrast enhanced sonography with gastric distention

Comparing endoscopic ultrasonography and double contrast-enhanced ultrasonography in the preoperative diagnosis of gastric stromal tumor

BACKGROUND

This study was designed to perform a comparative analysis between endoscopic ultrasonography (EUS) and double contrast-enhanced ultrasonography (DCEUS) for the preoperative diagnosis of gastric stromal tumors (GSTs).

METHODS

A retrospective study was conducted involving 139 patients with histologically confirmed GSTs. All patients preoperatively underwent DCEUS and EUS. The pathology reports were treated as the baseline and were retrospectively compared with the findings of EUS and DCEUS.

RESULTS

Of the 139 lesions, 120 and 113 were correctly identified by DCEUS and EUS, respectively, with an accuracy of 86.3% and 81.3%. The results revealed an insignificant difference between these two methods (p = 0.189).

CONCLUSIONS

DCEUS can display not only the locations, sizes, shapes, borders, internal echoes, but also show the blood perfusion patterns of GSTs. It is a highly accurate, noninvasive, and convenient method to be used at the pre-treatment stage.

Risk stratification of gastric cancer screening in community population based on oral contrast-enhanced ultrasonography examination: A 3-year follow-up analysis report

Objective

This study aimed to retrospectively investigate the use of oral contrast-enhanced ultrasonography (O-CEUS) in assessing the thickness of the gastric wall for gastric cancer (GC) screening and to establish screening strategies for GC with different risk stratifications based on the gastric wall thickness.

Methods

From January 2015 to March 2020, people who underwent O-CEUS at the Physical Examination Center of our hospital with at least three years of follow-up were included in this study. The thickness of the gastric wall measured by O-CEUS was divided into three groups using 6 mm and 9 mm as cutoff values. The occurrence of GC in each group was observed. The imaging and clinical information of these populations were recorded and analyzed. Kaplan-Meier survival analysis and Cox's proportional hazards regression were performed to calculate the risk of GC occurrence.

Results

A total of 4,047 people were finally included in this study. During the follow-up period, GC occurred in 7 individuals (incidence rate 0.17%). Among them, according to the thickness of the gastric wall, one case occurred in Group A (< 6 mm), two cases occurred in Group B (6-9 mm), and four cases occurred in Group C (>9mm). Based on Kaplan-Meier survival analysis, the curves of the three groups were significantly different (P < 0.01). The risk of GC occurrence in Group C and Group B were higher than that in Group A (4.76E+2-fold and 1.50E+2-fold).

Conclusion

O-CEUS is a convenient, economical, safe, and noninvasive screening method for GC. Measuring the thickness of the gastric wall is helpful to predict the risk of GC occurrence according to our stratification screening system.

Dynamic contrast enhanced ultrasound in gastrointestinal diseases: A current trend or an indispensable tool?

Contrast enhanced ultrasound (CEUS) has been widely implemented in clinical practice because of the enormous quantity of information it provides, along with its low cost, reproducibility, minimal invasiveness, and safety of the second-generation ultrasound contrast agents. To overcome the limitation of CEUS given by the subjective evaluation of the contrast enhancement behaviour, quantitative analysis of contrast kinetics with generation of time-intensity curves has been introduced in recent years. The quantification of perfusion parameters [named as dynamic-CEUS (D-CEUS)] has several applications in gastrointestinal neoplastic and inflammatory disorders. However, the limited availability of large studies and the heterogeneity of the technologies employed have precluded the standardisation of D-CEUS, which potentially represents a valuable tool for clinical practice in management of gastrointestinal diseases. In this article, we reviewed the evidence exploring the application of D-CEUS in gastrointestinal diseases, with a special focus on liver, pancreas, and inflammatory bowel diseases.

Clinical Study on the Evaluation of the Condition of Patients with Gastric Tumors and the Choice of Surgical Treatment by Gastric Ultrasonic Filling Method

OBJECTIVE

To explore the clinical value of the gastric ultrasonic filling method in evaluating the condition of patients with gastric tumors and guiding the selection of treatment methods, provide data support for clinical gastric filling ultrasonography in the evaluation of gastric cancer patients, and provide the basis for the choice of surgical treatment. Methods. This study retrospectively analyzed 50 patients with gastric cancer treated in our hospital from April 2017 to January 2022. All 50 patients were examined by the gastric ultrasound filling method. The TNM staging results of gastric cancer were analyzed with the results of gastroscopic biopsy or postoperative pathological examination as the diagnostic gold standard. Results. The ultrasonic detection rate of 50 patients with gastric cancer was 94.00% (47/50). Among them, 3 cases missed diagnosis were of early intramucosal carcinoma, which were only diagnosed as erosive gastritis. 1 case was located in the gastric body, and the other 2 cases were located in the gastric antrum. Ultrasound assessment of gastric mucosal thickness in T1-T2 stage was 9.8 mm, which was significantly lower than that in T3-T4 stage, which was 17.0 mm (p < 0.05). The diagnostic accuracy of the gastric ultrasound filling method in the diagnosis of T1, T2, T3, and T4 was 41.67%, 57.14%, 96.00%, and 83.33%, respectively. The total diagnostic accuracy of T-stage was 76.00% (38/50). The total judgment rate of too shallow and too deep was 10.00% and 14.00%, respectively. The diagnostic accuracy of the gastric ultrasound filling method was 88.89%, 81.81%, 70.00%, and 82.00%, respectively. The diagnostic accuracy of the gastric ultrasound filling method in the diagnosis of M0 and M1 stages was 100.00%, and the total diagnostic accuracy of the M-stage was 100.00%. The ROC curve drawn by GFUS in the diagnosis of T-stage of gastric cancer had three components: the specificity was the horizontal axis, the sensitivity was the vertical axis, and the area under the curve was 0.978. The difference was statistically significant (p < 0.05). Conclusion. Before the operation of patients with gastric cancer, using the gastric ultrasonic filling method and ultrasonic examination method to diagnose them can timely clarify the clinical stage of patients, so that clinicians can choose the most appropriate operation method according to their clinical stage, which is worthy of popularization and application in clinic.

Gastric Cancer Angiogenesis Assessment by Dynamic Contrast Harmonic Imaging Endoscopic Ultrasound (CHI-EUS) and Immunohistochemical Analysis-A Feasibility Study

Tumor vascular perfusion pattern in gastric cancer (GC) may be an important prognostic factor with therapeutic implications. Non-invasive methods such as dynamic contrast harmonic imaging endoscopic ultrasound (CHI-EUS) may provide details about tumor perfusion and could also lay out another perspective for angiogenesis assessment. Methods: We included 34 patients with GC, adenocarcinoma, with CHI-EUS examinations that were performed before any treatment decision. We analyzed eighty video sequences with a dedicated software for quantitative analysis of the vascular patterns of specific regions of interest (ROI). As a result, time-intensity curve (TIC) along with other derived parameters were automatically generated: peak enhancement (PE), rise time (RT), time to peak (TTP), wash-in perfusion index (WiPI), ROI area, and others. We performed CD105 and CD31 immunostaining to calculate the vascular diameter (vd) and the microvascular density (MVD), and the results were compared with CHI-EUS parameters. Results: High statistical correlations (p < 0.05) were observed between TIC analysis parameters MVD and vd CD31. Strong correlations were also found between tumor grade and 7 CHI-EUS parameters, p < 0.005. Conclusions: GC angiogenesis assessment by CHI-EUS is feasible and may be considered for future studies based on TIC analysis.

Ultrasonography in infectious and neoplastic diseases of the bowel and peritoneum

Ultrasonography is not the most cited imaging technique for the evaluation of infectious and neoplastic diseases of the gastrointestinal tract and the peritoneum, but it is often the initial technique used in the initial workup for nonspecific clinical syndromes. Despite its limitations, ultrasonography's strengths enable it to provide meaningful diagnostic information. To discuss the most important ultrasonographic, clinical, and epidemiological findings for infectious disease, we follow a topographical approach: stomach (Anisakis), proximal small bowel (Giardia lamblia, Strongyloides stercoralis, Mycobacterium avium-intracellulare complex, and Cryptosporidium), distal small bowel (Yersinia, Salmonella, and Campylobacter), terminal ileum and cecum (tuberculosis), right colon (Entamoeba histolytica), left colon (Shigella), sigmoid colon and rectum, pancolitis (Clostridium difficile, Cytomegalovirus, and Escherichia coli), and peritoneum. To discuss the ultrasonographic and clinical findings of the most common neoplastic diseases, we follow a nosological approach: polyploid lesions as precursors of tumors, carcinomas, neuroendocrine tumors, hematological tumors, mesenchymal tumors, and metastases. We briefly discuss tumors of the peritoneum and the use of ultrasonography to guide percutaneous biopsy procedures.

Dynamic Contrast-Enhanced Ultrasound of Gastric Cancer: Correlation with Perfusion CT and Histopathology

Objective

To assess the relationship between contrast-enhanced ultrasound (CEUS) parameters and perfusion CT (PCT) parameters of gastric cancers and their correlation with histologic features.

Materials and Methods

This prospective study was approved by our Institutional Review Board. We included 43 patients with pathologically-proven gastric cancers undergoing CEUS using SonoVue® (Bracco) and PCT on the same day. Correlation between the CEUS parameters (peak intensity [PI], area under the curve [AUC], rise time [RT] from 10% to 90% of PI, time to peak [TTP_US], and mean transit time [MTT_US]) and PCT parameters (blood flow, blood volume, TTP_CT, MTT_CT, and permeability surface product) of gastric cancers were analyzed using Spearman's rank correlation test. In cases of surgical resection, the CEUS and PCT parameters were compared according to histologic features using Mann-Whitney test.

Results

CEUS studies were of diagnostic quality in 88.4% (38/43) of patients. Among the CEUS parameters of gastric cancers, RT and TTP_US showed significant positive correlations with TTP_CT (rho = 0.327 and 0.374, p = 0.045 and 0.021, respectively); PI and AUC were significantly higher in well-differentiated or moderately-differentiated tumors (n = 4) than poorly-differentiated tumors (n = 18) (p = 0.026 and 0.033, respectively), whereas MTT_CT showed significant differences according to histologic types (poorly cohesive carcinoma [PCC] vs. non-PCC), T-staging (≤ T2 vs. ≥ T3), N-staging (N0 vs. N-positive), and epidermal growth factor receptor expression (≤ faint vs. ≥ moderate staining) (p values < 0.05).

Conclusion

In patients with gastric cancers, CEUS is technically feasible for the quantification of tumor perfusion and may provide correlative and complementary information to that of PCT, which may allow prediction of histologic features.

Value of contrast-enhanced harmonic endoscopic ultrasonography in differentiating between gastrointestinal stromal tumors: A meta-analysis

OBJECTIVE

Contrast-enhanced harmonic endoscopic ultrasonography (CH-EUS) is a valuable device to diagnose and determine the malignant potential of gastrointestinal stromal tumors (GIST) as early as possible when making clinical therapeutic decisions. This study aimed to estimate the ability of CH-EUS to discriminate between GIST and benign submucosal lesions (SML) and to predict their malignant potential.

METHODS

PubMed, MEDLINE, EMBASE, the Web of Science, and Cochrane Central Register of Controlled Trials databases were screened. Using the data provided in the literatures, 2 × 2 tables were constructed to obtain the pooled sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio. A receiver operating characteristic (ROC) curve was generated and the area under the ROC curve (AUROC) was calculated.

RESULTS

Four studies with a total of 187 patients were identified to evaluate the value of CH-EUS in discriminating between GIST and benign SML. The pooled sensitivity, specificity, and AUROC were 89% (95% CI 0.82-0.93), 82% (95% CI 0.66-0.92), and 0.89, respectively. Five studies including 143 patients were analyzed to assess the accuracy of CH-EUS in determining the malignant potential of GIST. The pooled sensitivity, specificity, and AUROC curve of CH-EUS were 96% (95% CI 0.90-0.99), 53% (95% CI 0.40-0.66), and 0.92, respectively.

CONCLUSIONS

CH-EUS is a safe, noninvasive method that can distinguish between GIST and benign subepithelial lesions and to predict their malignant potential to a certain extent. Large-scale, multicenter prospective studies are needed in the future.

Double Contrast-Enhanced Ultrasonography in Preoperative T Staging of Gastric Cancer: A Comparison With Endoscopic Ultrasonography

Objective: To compare the precision of double contrast-enhanced ultrasonography (DCEUS) to endoscopic ultrasonography (EUS) in preoperative T staging of gastric cancers.

Methods: This retrospective study consisted of 158 pathologically confirmed gastric cancer patients. All patients underwent DCEUS (intravenous contrast-enhanced ultrasonography combined with oral contrast-enhanced ultrasonography) and endoscopic ultrasonography (EUS) preoperatively. The histopathological findings of resected specimens were compared with the results of DCEUS and EUS retrospectively.

Results: The accuracy of DCEUS and EUS in evaluating the T staging of gastric cancer were 82.3% (T1 62.5%,T2 84.4%,T3 87.9%,T4 91.3%) and 76.6% (T1 84.4%,T2 82.2%,T3 72.4%,T4 65.2%), respectively. There were no significant differences between the methods for the overall T staging accuracy (χ² = 1.569, P = 0.210). But EUS was superior to DCEUS for T1 stage (χ² = 3.925, P = 0.048) and DCEUS was superior to EUS for T3 stage (χ² = 4.393, P = 0.036) and T4 stage (χ² = 4.600, P = 0.032).

Conclusion: DCEUS is a convenient and noninvasive method with high precision, which can be used as the primary imaging technique for advanced gastric cancer T staging. In early gastric cancer, we should prefer EUS. Two methods are complementary for assessing tumor invasion depth of gastric cancer.

Pitfalls in ultrasound imaging of the stomach and the intestines

The gastrointestinal tract is an extraordinary human organ in terms of its morphology and function. Its complex structure and enormous length as well as frequent presence of gas discourage many doctors performing ultrasound examination from its exploration. Moreover, there are anatomical structures in multiple locations which can mimic certain abnormalities. It is difficult to present an exhaustive account of the problem of gastrointestinal tract ultrasound imaging errors in a single work; therefore, this study focuses mainly on false positive errors which usually result from a lack of knowledge of anatomical variants of the gastrointestinal tract structure. In the case of the stomach, rugae and muscle layer thickening towards the pylorus have been mentioned, which constitute variants of the structure of this organ examined when empty. Diagnostic pitfalls in the small intestine may include the dudenojejunal flexure (ligament of Treitz), the horizontal part of the duodenum and the ileocaecal valve. The status of the apparent lesions in all of the cases mentioned will be resolved following fluid intake by the patient. In the colon, the varied structure of semilunar folds should be taken note of. Their large thickness can warrant suspicion of wall invasion or a polyp. In addition, the study emphasises the importance of appropriate preparation of a patient for gastrointestinal tract examination since it determines the accuracy of the diagnosis. The authors also take note of common ‘sins’ of physicians such as hasty examination and failure to comply with the stomach and appendix examination protocol.