三原 修一, 大竹 宏治, 木場 博幸, 田中 信次, 平尾 真一

Shuichi MIHARA, Kouji OTAKE, Hiroyuki KOBA, Shinji TANAKA, Shinichi HIRAO

日本赤十字社熊本健康管理センター

Japanese Red Cross Kumamoto Health Care Center

キーワード : US screening, early detection, renal cell carcinoma, ureteropelvic cancer, bladder carcinoma

1983年度から2003年度までの腹部超音波検診受診者延べ1,375,565名から1,403例の悪性疾患が発見された．そのうち腎泌尿器の悪性疾患は，腎細胞癌337例，腎盂尿管癌18例，膀胱癌123例，前立腺癌62例など545例で，38.8％を占めた．腎細胞癌，腎盂尿管癌，膀胱癌，前立腺癌の切除例はそれぞれ332例（98.5％），16例（88.9％），121例（98.4％），10例（16.1％），切除例の10年生存率は腎細胞癌96.8％，腎盂尿管癌52.0％，前立腺癌100％，膀胱癌では7年生存率99.1％であった．腎細胞癌は病期 I が86％，膀胱癌は病期 I が98.3％を占めたのに対し，腎盂尿管癌では病期 I が33.3％，病期III・IVが60％であった．膀胱癌では98.3％がTUR-Btにて治療された．超音波検診は，腎細胞癌，膀胱癌の早期発見にきわめて有用である．小腎細胞癌は高エコー均一な腫瘍が多く，血管筋脂肪腫との鑑別が重要である．また，腫瘍径の増大とともに，不均一になる．嚢胞タイプの腎癌では，壁の肥厚や内部の充実エコーに注意することが発見のポイントになる．腎盂尿管癌では，CEC内の充実エコー像やCECの経時的変化，水腎・水尿管に注意する．膀胱癌は後壁（三角部）に多発し，隆起性病変の検出がポイントである．

From 1983 through 2003, 1,403 cases of malignant neoplasm were detected among 1,375,565 examinees who underwent abdominal US screening. In these cases, 545 cases (38.8%) were detected from kidney and urinary organs, such as 337 renal cell carcinoma (RCC), 18 ureteropelvic cancer, 123 bladder carcinoma, 62 prostate cancer, and so on. The resected cases of RCC, ureteropelvic cancer, bladder carcinoma, and prostate cancer were 332 (98.5%), 16 (88.9%), 121 (98.4%), and 10 (16.1%), respectively. The cumulative survival rate of these cases was 96.8% at 10 y, 52.0% at 10 y, 99.1% at 7 y, and 100% at 10 y, respectively. The percentage of cases with stage I disease was 86% in RCC and 98.3% in bladder carcinoma. On the other hand, in ureteropelvic cancer, the percentage of cases with stage I disease was 33.3%, and the percentage with stage III or IV disease were 60%. In bladder carcinoma, 98.3% of the cases were treated by TUR-Bt. US screening was extremely useful for early detection of RCC and bladder carcinoma. The internal echo pattern of many small RCCs was hyperechoic and homogeneous, and it was very important to distinguish it from angiomyolipoma. Moreover, the heterogeneous type increased with the size of the tumor. In cystic type RCCs, the US features of thickened wall and solid component in the tumor were important for early detection. In ureteropelvic cancer, solid echo in CEC, change of CEC echo with the passage of time, and hydronephrosis and/or hydroureter should be evaluated very carefully. Bladder carcinoma is frequently detected at the triangle of the bladder, and it is very important to detect elevated lesions.