Clinical value of oral contrast-enhanced ultrasonography in diagnosis of gastric tumors.

BACKGROUND: The incidence of gastric cancer remains high, and it is the sixth most common cancer and the fourth leading cause of cancer deaths worldwide. Oral contrast-enhanced ultrasonography is a simple, non-invasive, and painless method for the diagnosis of gastric tumors. AIM: To explore the diagnostic value of oral contrast-enhanced ultrasonography for the detection of gastric tumors. METHODS: The screening results based on oral contrast-enhanced ultrasonography and electronic gastroscopy were compared with those of the postoperative pathological examination. RESULTS: Among 42 patients with gastric tumors enrolled in the study, the diagnostic accordance rate was 95.2% for oral contrast-enhanced ultrasonography (n = 40) and 90.5% for electronic gastroscopy (n = 38) compared with postoperative pathological examination. The Kappa value of consistency test with pathological findings was 0.812 for oral contrast-enhanced ultrasonography and 0.718 for electronic gastroscopy, and there was no significant difference between them (P = 0.397). For the TNM staging of gastric tumors, the accuracy rate of oral contrast-enhanced ultrasonography was 81.9% for the overall T staging and 50%, 77.8%, 100%, and 100% for T1, T2, T3, and T4 staging, respectively. The sensitivity and specificity were both 100% for stages T3 and T4. The diagnostic accuracy rate of oral contrast-enhanced ultrasonography was 93.8%, 80%, 100%, and 100% for stages N0, N1-N3, M0, and M1, respectively. CONCLUSION: The accordance rate of qualitative diagnosis by oral contrast-enhanced ultrasonography is comparable to that of gastroscopy, and it could be used as the preferred method for the early screening of gastric tumors.

High-resolution melting analysis is a more effective approach for screening TSC genes mutations.

Tuberous sclerosis complex (TSC) is an autosomal dominant disorder with a prevalence of 1 in 95,136 in Taiwan. TSC is characterized by hamartomatous lesions in multiple organ systems. Genetic defects in TSC1 and TSC2 genes are the main causes of TSC. A molecular screening protocol using denaturing high-performance liquid chromatography (dHPLC) followed by DNA sequencing is currently performed to locate the genetic lesions in many clinical laboratories. The current screening approach is time consuming and inefficient. In this study, we analyzed all coding exons of TSC1 and TSC2 genes of 30 TSC patients and 47 unaffected family members using the traditional dHPLC protocol and our recently developed diagnostic platform based on high-resolution melting analysis (HRM) followed by bidirectional DNA sequencing. Data indicated that 20 mutations, including 5 mutations in TSC1 (2 sporadic, 1 familial mutation, and 2 of uncertain origin) and 15 mutations in TSC2 (14 sporadic and 1 familial mutation), 8 single-nucleotide polymorphisms (SNPs, including 3 SNPs found in irrelevant individuals without TSC phenotypes studied in the control group), and 3 variants with undetermined significance were identified, including 4 novel mutations. The sensitivities of HRM and dHPLC for TSC mutation screening were estimated as 95% and 75%, respectively. The specificities of HRM and dHPLC for TSC mutation screening were evaluated as 91% and 98%. In addition, results suggested our novel HRM screening protocol to be more economical. In conclusion, we successfully developed a superior approach for TSC genes mutation screening for clinical application.