三原 修一

Shuichi MIHARA

日本赤十字社熊本健康管理センター

Kumamoto Red Cross Health Care Center

キーワード : Renal cell carcinoma, Ultrasonic mass survey, Early detection, Ultrasonographic findings

From Aug. 1983 through Mar. 1990, 104, 696 people received first-time uutrasonic mass evaluations. The survey was conducted in our Health Care Center, in rural districts, and in occupational areas. Among these subjects, sixty (0.06%) renal cell carcinoma (RCC) cases were found and all of them were curatively resected. Fifteen cases (25.4%) were less than 25 mm in size (T1). The cumulative survival rate of all cases after seven years was 97.3%. Furthermore, no metastasis of lymph nodes or other organs was found in any of the cases. Ultrasonic mass survey is essential for early detection of RCC. From now on, RCC cases can be detected earlier by establishing and promoting ultrasonic mass survey systems.
Next, we analyzed in detail the ultrasonographic findings of these RCC cases. The internal echo of a large percentage (80%) of small RCC cases (T1) were homogeneous and hyperechoic, and showed lower echogenicity than the central echo complex: in addition, the carcinoma became heterogeneous as they grew. The fact that eighty percent of T1 cases were the pT2b type (protruding from the surface of the kidney) will be valuable in early detection of small RCC cases, too.