Assessment of abdominal sonography in the diagnosis of tumors of the gastroduodenal tract.

This prospective study was conducted to assess the sensitivity, specificity, and predictive values of abdominal sonography for detecting tumors of the gastroduodenal tract. All examinations were carried out by the same sonographer who was unaware of endoscopic features and the results of X-ray examinations. The stomach was identified in 99% of the 423 patients examined. In fasting conditions, values were 64.6% and 72.4% using the 3.5-MHz and 7.5-MHz transducer, respectively, and increased up to 94.3% and 93.2% for fluid-filled stomachs. Of a total of 72 tumors identified by endoscopic examination, 56 were detected ultrasonographically. There were 16 false-negative and 3 false-positive results, for a sensitivity of 77.8% (95% CI, 66.4% to 86.7%), specificity of 99.1%, positive predictive value of 94.9%, and negative predictive value of 95.5%. Conventional ultrasound is a simple, rapid, and useful method to detect tumors of the gastroduodenal tract, particularly in the fluid-filled stomach. A high resolution is obtained with 7.5-MHz transducers, especially for tumors of the antropyloric region.