Prospective observational study of the incidental findings on endoscopic ultrasonography: should a complete exploration always be performed?

OBJECTIVES: To quantify the additional non-suspected new diagnoses made on upper endosonography (EUS) which were unknown before the procedure, and to analyse their influence on the management of patients. A further objective was to evaluate the influence that previous radiological or endoscopic explorations have on the capacity of EUS to diagnose these unsuspected lesions.
MATERIAL AND METHODS: During a 2-year period every patient sent to our unit for upper EUS underwent a complete investigation, after signing an informed consent document. An upper EUS was considered as complete whenever the gut wall, pancreas, biliary tract, ampulla, large abdominal vessels, liver, spleen, left adrenal gland, posterior mediastinum and thyroid lobes had been explored. An additional diagnosis (AD) was defined as a diagnosis made on EUS that was previously unknown and not suspected. A significant additional diagnosis (SAD) was defined as an AD that required further study. The results of complementary explorations carried out before EUS were registered.
RESULTS: A total of 239 patients were included in the study. ADs were found in 92 patients (38.5%), which were considered to be SADs in 27 patients (11.3%). Those patients had previously undergone computed tomography (CT) and those who underwent more than one exploration had fewer incidences of ADs on EUS (p=0.03 and p=0.02, respectively). No exploration alone or in combination with others showed any influence on the capacity of EUS to find a SAD (p >0.05).
CONCLUSIONS: In our series, an AD was found on upper endosonography in 38.5% of the patients studied, and a SAD in 11.3%. The probability of finding a SAD on EUS is not influenced by previous endoscopic or radiologic explorations.