Diagnostic Accuracy of Double Contrast-Enhanced Ultrasonography in Clarifying Tumor Depth (T Stage) of Gastric Cancer: Meta-analysis

Diagnostic efficacy of contrast-enhanced gastric ultrasonography in staging gastric cancer: a meta-analysis

BACKGROUND

As comprehensive surgical management for gastric cancer becomes increasingly specialized and standardized, the precise differentiation between ≤T1 and ≥T2 gastric cancer before endoscopic intervention holds paramount clinical significance.

OBJECTIVE

To evaluate the diagnostic efficacy of contrast-enhanced gastric ultrasonography in differentiating ≤T1 and ≥T2 gastric cancer.

METHODS

PubMed, Web of Science, and Medline were searched to collect studies published from January 1, 2000 to March 16, 2023 on the efficacy of either double contrast-enhanced gastric ultrasonography (D-CEGUS) or oral contrast-enhanced gastric ultrasonography (O-CEGUS) in determining T-stage in gastric cancer. The articles were selected according to specified inclusion and exclusion criteria, and the quality of the included literature was assessed using the Quality Assessment of Diagnostic Accuracy Studies-2 scale. Meta-analysis was performed using Stata 12 software with data from the 2 × 2 crosslinked tables in the included literature.

RESULTS

In total, 11 papers with 1124 patients were included in the O-CEGUS analysis, which revealed a combined sensitivity of 0.822 (95% confidence interval [CI] = 0.753-0.875), combined specificity of 0.964 (95% CI = 0.925-0.983), and area under the summary receiver operating characteristic (sROC) curve (AUC) of 0.92 (95% CI = 0.89-0.94). In addition, five studies involving 536 patients were included in the D-CEGUS analysis, which gave a combined sensitivity of 0.733 (95% CI = 0.550-0.860), combined specificity of 0.982 (95% CI = 0.936-0.995), and AUC of 0.93 (95% CI = 0.91-0.95). According to the I2 and P values ​​of the forest plot, there was obvious heterogeneity in the combined specificities of the included papers. Therefore, the two studies with the lowest specificities were excluded from the O-CEGUS and D-CEGUS analyses, which eliminated the heterogeneity among the remaining literature. Consequently, the combined sensitivity and specificity of the remaining studies were 0.794 (95% CI = 0.710-0.859) and 0.976 (95% CI = 0.962-0.985), respectively, for the O-CEDUS studies and 0.765 (95% CI = 0.543-0.899) and 0.986 (95% CI = 0.967-0.994), respectively, for the D-CEGUS studies. The AUCs were 0.98 and 0.99 for O-CEGUS and D-CEGUS studies, respectively.

CONCLUSION

Both O-CEGUS and D-CEGUS can differentiate ≤T1 gastric cancer from ≥T2 gastric cancer, thus assisting the formulation of clinical treatment strategies for patients with very early gastric cancer. Given its simplicity and cost-effectiveness, O-CEGUS is often favored as a staging method for gastric cancer prior to endoscopic intervention.

The value of colorectal filling contrast ultrasonography in diagnosing pediatric juvenile polyps

OBJECTIVES

To describe a facilitated procedure of colorectal filling contrast ultrasonography (CFCUS) and explore its value in the diagnosis of pediatric juvenile polyps.

METHODS

One hundred and eleven children with clinical signs of colorectal polyps admitted to our hospital between May 2018 and May 2021 were retrospectively reviewed. All children underwent conventional transabdominal ultrasonography (CTUS) and CFCUS prior to undergoing colonoscopy. Pathologic findings were used as the gold standard. Chi-squared tests and Mann-Whitney U tests were used for the statistical analysis.

RESULTS

Forty-five children with fifty-two colorectal polyps were confirmed via pathological examination. The sensitivity, specificity, positive predictive value, and negative predictive value of CFCUS vs. CTUS were 92.3% versus 80.7%, 100% versus 100%, 100% versus 100%, and 93.3% versus 84.8%, respectively. The missed polyps were significantly smaller than the polyps detected in diameter (7.50 ± 2.12 mm vs. 19.62 ± 7.89 mm, p < 0.0001) by CTUS. A significant difference between CTUS and CFCUS was observed in the detection rate of polyps with a diameter < 1 cm (p = 0.031) and pedicles (p < 0.001). The kappa values for the assessment of Yamada's classification between CTUS and colonoscopy and CFCUS and colonoscopy were 0.51 and 0.84, respectively. Moreover, CFCUS incidentally revealed a punctate hyperechoic area on the surface of colonic polyps in six cases, which may be suggestive of a correlation with erosion and bleeding findings.

CONCLUSION

CFCUS can increase the detection rate of polyps and pedicles, especially polyps with diameters <1 cm, and accurately evaluate Yamada's classification, providing useful preoperative information for colonoscopy.

Updated Evaluation of the Diagnostic Performance of Double Contrast-Enhanced Ultrasonography in the Preoperative T Staging of Gastric Cancer: A Meta-Analysis and Systematic Review

Objective

This study aimed to systematically evaluate the diagnostic performance of double contrast-enhanced ultrasonography (DCEUS) in the preoperative T staging of gastric cancer (GC).

Methods

Literature searches for eligible studies were performed using MEDLINE, EMBASE, and Cochrane Library. The pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio, and area under the summary receiver operating characteristic curve of DCEUS in the diagnosis of each T stage tumor were calculated. Meta-analyses were performed to obtain the pooled effects of risk ratio (RR) with 95% confidence interval (CI) in the comparison of DCEUS with CT/endoscopic ultrasound (EUS).

Results

A total of 8 studies including 1,232 patients were identified for inclusion in this meta-analysis. The pooled sensitivity and specificity were 0.78 (95% CI = 0.64–0.88) and 0.98 (95% CI = 0.96–0.99) for T1, 0.81 (95% CI = 0.76–0.86) and 0.96 (95% CI = 0.91–0.98) for T2, 0.88 (95% CI = 0.84–0.91) and 0.85 (95% CI = 0.79–0.90) for T3, and 0.81 (95% CI = 0.69–0.89) and 0.96 (95% CI = 0.93–0.97) for T4. Moreover, DCEUS demonstrated significant superiority to CT in diagnosing T1 (RR = 1.57, 95% CI = 1.20–2.05, p = 0.001) and T2 (RR = 1.41, 95% CI = 1.16–1.71, p = 0.001) and to EUS in diagnosing T3 (RR = 1.24, 95% CI = 1.08–1.42, p = 0.003) and T4 (RR = 1.40, 95% CI = 1.09–1.79, p = 0.008). However, it showed a lower diagnostic accuracy than EUS in T1 tumors (RR = 0.77, 95% CI = 0.62–0.94, p = 0.013).

Conclusions

DCEUS is a feasible complementary diagnostic tool for clinical T staging of GC. However, it is still far from a definitive conclusion for DCEUS to be proposed for use in routine clinical practice.