The remarkable progress and spread of ultrasonic diagnostic equipment has maid it possible to diagnose various diseases more easily and quickly.
From August, 1983, we began to examine abdominal organs such as the liver, gallbladder, pancreas, kidney, spleen, and bile duct using ultrasonic diagnostic equipment in the Health Care Center. On the other hand, we began ultrasonographic (US) mass screening for the people in the rural areas and occupational areas from March, 1984.
We examined 9803 subjects in the Health Care Center and 11558 subjects in 23 rural areas and 15 occupational areas of Kumamoto Prefecture through June, 1986. Among these 21361 subjects, 6882 (32.2 percent) cases showed abnormal findings. Main diseases detected by US screening were gallstone, gallbladder polyp, liver cyst, liver tumor, renal cyst, renal tumor, renal stone, and so on.
In the Health Care Center we could find 23 cancer cases such as two gallbladder cancer cases, seven hepatoma cases, twelve renal cell carcinoma cases, one bile duct carcinoma case, and one gastric cancer case. The prevalence rate was 0.23 percent. On the other hand, 14 cancer cases such as two gallbladder cancer cases, three hepatoma cases, two metastatic liver cancer cases, four renal cell carcinoma cases, one transitional cell carcinoma case of the kidney, and one pancreas cancer case were found in the US mass screening. The prevalence rate was 0.12 percent.
By using ultrasonic diagnostic equipment, we can find many latent diseases which show no abdominal findings by the traditional screening systems. Especially the fact that we discovered many cancer cases and the majority of them were operated on in their early stage was highly important. If we had no chance to examine these patients by US examination, these cancer cases could probably not have been discovered.
To conqure various problems such as the training of examiners, the systematization of these thorough examinations as well as post examination therapy, and the education of examinees will difinitely contribute significantly to the effectiveness of the US mass screening method.