0022-5347/79/1215-0675$02.00/0 Vol. 121, May Printed in U.S.A.
THE JOURNAL OF UROLOGY
Copyright © 1979 by The Williams & Wilkins Co.
RENAL ANGIOMYOLIPOMA: DIAGNOSIS BY COMBINED ULTRASOUND AND COMPUTERIZED TOMOGRAPHY T. H. SHAWKER,* K. L. HORVATH, N. R. DUNNICK
AND
N. JAVADPOUR
From the Diagnostic Radiology Department, The Clinical Center and the Surgery Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland
ABSTRACT
A case is presented of a 2 cm. renal angiomyolipoma. Computerized tomography demonstrated a region of low attenuation coefficient within this tumor, while B-mode ultrasound visualizes the tumor as a cluster of high amplitude echoes. The diagnosis of a renal angiomylipoma may be suspected preoperatively when this combination of findings is present with computerized tomography and ultrasound. Although renal angiomyolipomas most frequently occur in association with tuberous sclerosis they may occur independently as single, unilateral renal masses. When these tumors are unassociated with tuberous sclerosis they usually are not diagnosed preoperatively. An angiomyolipoma consists of a mixture of adipose tissue, blood vessels and smooth muscle in varied proportions. 1 Previous ultrasonic studies of angiomyolipomas have shown that, unlike renal cysts or most renal cell carcinomas, these tumors present a cluster of high amplitude internal echoes, probably because of their high fat content. 2 • 3
CASE REPORT
A 68-year-old woman with stage I diffuse, non-Hodgkin's lymphoma in complete remission was hospitalized in July 1977 for the evaluation of a right renal mass that had been detected incidentally on abdominal computerized tomography. Computerized tomography examination revealed a well defined, low density mass within the posterolateral right renal cortex (partA of figure). The density of the lesion was similar to that of the perirenal fat. Ultrasound examination revealed
A, computerized tomography of right kidney shows region oflow attenuation coefficient (arrows) in posterior cortex of right kidney. B, ultrasound of right kidney, transverse view with patient supine, demonstrates echo-dense poorly marginated mass (arrows) in posterior cortex of right kidney. K, kidney. L, liver.
This fatty component also can be identified as a region of low attenuation coefficient on computerized tomography. 4 A case is presented of a 2 cm. renal angiomyolipoma, in which the diagnosis was suggested preoperatively by the combined use of ultrasound and computerized tomography. Excision of the mass rendered the patient free of tumor with preservation of the involved kidney.
a 2 cm. intrarenal mass in the same location, which showed high amplitude internal echoes and relatively poor margination (partB of figure). A subsequent selective renal angiogram demonstrated the lesion to be avascular. A 2 cm. yellow, fatty, non-encapsulated mass was resected along with 2 mm. normal surrounding renal parenchyma. The final histological diagnosis was renal angiomyolipoma.
DISCUSSION Accepted for publication August 18, 1978. * Requests for reprints: Diagnostic Radiology Department, Bldg. The identification of a fatty component within a renal tumor 10, Rm. 68211, National Institutes of Health, The Clinical Center, is virtually diagnostic of angiomyolipomas but plain abdomiBethesda, Maryland 20014. 675
676
SHAWKER AND ASSOCIATES
nal x-rays reveal this fat in
THE JOURNAL OF UROLOGY
Copyright © 1979 by The Williams & Wilkins Co.
RENAL ANGIOMYOLIPOMA: DIAGNOSIS BY COMBINED ULTRASOUND AND COMPUTERIZED TOMOGRAPHY T. H. SHAWKER,* K. L. HORVATH, N. R. DUNNICK
AND
N. JAVADPOUR
From the Diagnostic Radiology Department, The Clinical Center and the Surgery Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland
ABSTRACT
A case is presented of a 2 cm. renal angiomyolipoma. Computerized tomography demonstrated a region of low attenuation coefficient within this tumor, while B-mode ultrasound visualizes the tumor as a cluster of high amplitude echoes. The diagnosis of a renal angiomylipoma may be suspected preoperatively when this combination of findings is present with computerized tomography and ultrasound. Although renal angiomyolipomas most frequently occur in association with tuberous sclerosis they may occur independently as single, unilateral renal masses. When these tumors are unassociated with tuberous sclerosis they usually are not diagnosed preoperatively. An angiomyolipoma consists of a mixture of adipose tissue, blood vessels and smooth muscle in varied proportions. 1 Previous ultrasonic studies of angiomyolipomas have shown that, unlike renal cysts or most renal cell carcinomas, these tumors present a cluster of high amplitude internal echoes, probably because of their high fat content. 2 • 3
CASE REPORT
A 68-year-old woman with stage I diffuse, non-Hodgkin's lymphoma in complete remission was hospitalized in July 1977 for the evaluation of a right renal mass that had been detected incidentally on abdominal computerized tomography. Computerized tomography examination revealed a well defined, low density mass within the posterolateral right renal cortex (partA of figure). The density of the lesion was similar to that of the perirenal fat. Ultrasound examination revealed
A, computerized tomography of right kidney shows region oflow attenuation coefficient (arrows) in posterior cortex of right kidney. B, ultrasound of right kidney, transverse view with patient supine, demonstrates echo-dense poorly marginated mass (arrows) in posterior cortex of right kidney. K, kidney. L, liver.
This fatty component also can be identified as a region of low attenuation coefficient on computerized tomography. 4 A case is presented of a 2 cm. renal angiomyolipoma, in which the diagnosis was suggested preoperatively by the combined use of ultrasound and computerized tomography. Excision of the mass rendered the patient free of tumor with preservation of the involved kidney.
a 2 cm. intrarenal mass in the same location, which showed high amplitude internal echoes and relatively poor margination (partB of figure). A subsequent selective renal angiogram demonstrated the lesion to be avascular. A 2 cm. yellow, fatty, non-encapsulated mass was resected along with 2 mm. normal surrounding renal parenchyma. The final histological diagnosis was renal angiomyolipoma.
DISCUSSION Accepted for publication August 18, 1978. * Requests for reprints: Diagnostic Radiology Department, Bldg. The identification of a fatty component within a renal tumor 10, Rm. 68211, National Institutes of Health, The Clinical Center, is virtually diagnostic of angiomyolipomas but plain abdomiBethesda, Maryland 20014. 675
676
SHAWKER AND ASSOCIATES
nal x-rays reveal this fat in
