Diagnostic value of contrast-enhanced ultrasonography in preoperative T-staging of gastric cancer / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To investigate the diagnostic value of contrast-enhanced ultrasonography (CEUS) in preoperative T-staging of gastric cancer.</p><p><b>METHODS</b>A sulfur hexafluoride-filled microbubble ultrasound contrast agent and a continuous real-time imaging technique of contrast pulse sequencing were used. Normal gastric wall was examined by CEUS in 8 healthy volunteers and the results were compared with the findings on multislice computed tomography. Sixty-two patients with gastric cancer proved by biopsies who received preoperative CEUS examination were involved in this study, and the CEUS result was compared with postoperative pathological findings.</p><p><b>RESULTS</b>The normal gastric wall presented a one-layer structure in the portal venous phase and a three-layer structure in the arterial and equilibrium phase including a slightly hyper-enhanced inner layer, a hypo-enhanced intermediate layer, and a markedly hyper-enhanced outer layer, which corresponded histologically to the mucosal, submucosal, and muscular-serosal layer, respectively. The accuracy of transabdominal ultrasonography and CEUS in determining the T stage of gastric cancer was 72.9% and 88.1% respectively, and the difference was statistically significant (chi(2)=4.37, P=0.036).</p><p><b>CONCLUSIONS</b>CEUS shows the normal gastric wall as a one- or a three-layer structure, which provides a theory base for CEUS in preoperative T-staging of gastric cancer. CEUS is a useful diagnostic method for preoperative T-staging of gastric cancer.</p>

Diagnostic value of double contrast-enhanced ultrasonography in preoperative staging of gastric cancer / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To evaluate the clinical value of double contrast-enhanced ultrasonography using oral and intravenous contrast agents in preoperative staging of gastric cancer.</p><p><b>METHODS</b>Sixty-two patients with biopsy-proven gastric cancer were enrolled into this study, and were examined by double contrast-enhanced gastric ultrasonography preoperatively. The results were compared with postoperative pathologic findings.</p><p><b>RESULTS</b>The accuracy of oral contrast-enhanced gastric ultrasonography and double contrast-enhanced ultrasonography in determining the T stage of gastric cancer was 72.9% (T1: 66.7%, T2: 60.0%, T3: 76.9%, T4: 71.4%) and 88.1% (T1: 66.7%, T2: 80.0%, T3: 89.7%, T4: 100%), respectively, with a statistically significant difference between the two methods (P = 0.036). The sensitivity, specificity, accuracy and Youden index of oral contrast-enhanced gastric ultrasonography and double contrast-enhanced ultrasonography in assessment of lymph node metastasis were 74.5%, 66.7%, 72.9%, and 0.41 versus 89.4%, 75.0%, 86.4%, 0.76, respectively. No significant difference in the accuracy of assessment for lymph node metastasis was observed (P > 0.05).</p><p><b>CONCLUSION</b>Double contrast-enhanced ultrasonography is useful for preoperative staging of gastric cancer, especially for T staging.</p>