Validity of sonographic screening for the detection of abdominal cancers

Purpose. This study assessed the prevalence of abdominal cancers and the validity of sonographic screening for abdominal cancers in an asymptomatic population. Methods. We investigated the findings of the first sonographic screening of 16,024 residents of Osaka Prefecture. A comparison of records was carried out between the list of those screened and the Osaka Cancer Registry to identify false-negative results of our screening. Results. The rate of subjects who required further testing after screening was 4.76% (762/16,024). Eleven of the 762 subjects with a positive sonographic screening study had abdominal cancers detected on further testing. Three subjects had false-negative screening results. The positive predictive value of sonographic screening was 1.4% (11/762), and the rate of screening-detected cancers was 0.069% (11/16,024). The prevalence of abdominal cancers was 0.087% (14/16,024), the sensitivity of screening sonography for the detection of abdominal cancers was 78.6% (11/14), and the specificity was 95.3% (15,259/16,010). Seven of 11 screening-detected cancers were resected curatively, and 6 of these patients are still alive. Five of these 6 cancers were renal cell carcinomas. Conclusions. The sensitivity of screening sonography was relatively high and the specificity was sufficient among our asymptomatic population. The present study suggests that the target organ for sonographic screening to detect curable cancers should be the kidneys. (C) 2002 Wiley Periodicals, Inc.