陳 敏華, 丁子 清, 小川 肇, 篠原 正裕, 藤田 信行, 森田 穣, 入江 五朗

Minhua CHEN, Kiyoshi CHOJI, Hajime OGAWA, Masahiro SHINOHARA, Nobuyuki FUJITA, Yutaka MORITA, Goro IRIE

北海道大学医学部放射線医学

Department of Radiology, Hokkaido University School of Medicine

キーワード : Ultrasound studies, Computed tomography, Kidney, Wilms' tumor, Neuroblastoma

Examination of boundaries between Wilms' tumor or neuroblastoma and the affected kidney was performed in 33 patients using either US or CT, or both. US assessment was done on nine patients with Wilms' tumor and 20 patients with neuroblastoma: CT assessment was done on eight with Wilms' tumor and ten with neuroblastoma. The type of the boundary was classified into six categories: I. The tumor is located apart from the kidney or touches it at one small point; II. The tumor surrounds a certain part of the kidney while the shape of the kidney remains unchanged; III. There is an extensive area of contact between the tumor and the kidney; the edges of the kidney at the interface appear roundish ("boomerang" appearance); IV. There is an extensive area of contact between the tumor and the kidney; one edge of the kidney at the interface appears roundish while the other has a sharp beak appearance; V. There is an extensive area of contact between the tumor and the kidney; both edges of the kidney at the interface are sharp ("crescent" appearance); VI. The image of the tumor eclipses, wholly or almost wholly, the image of the kidney, making identification of the kidney impossible, or almost impossible, and making classification of the boundary into categories I-V impossible. Alternatively, image of the kidney surrounds the image of the tumor.
Pathologically confirmed Wilms' tumor appeared as types V or VI in 100% of CT examinations and 89% of US examinations. Pathologically confirmed neuroblastoma appeared as types I, II, or III in 85% of US examinations and 90% of CT examinations. The findings permit a highly accurate differential diagnosis by both US (93%) and CT (94%) that types V and VI indicate Wilms' tumor and types I, II, III and IV indicate neuroblastoma.