TY - JOUR
T1 - Computed tomographic distinction of perirenal liposarcoma from exophytic angiomyolipoma
T2 - A feature analysis study
AU - Ellingson, James J.
AU - Coakley, Fergus V.
AU - Joe, Bonnie N.
AU - Qayyum, Aliya
AU - Westphalen, Antonio C.
AU - Yeh, Benjamin M.
PY - 2008
Y1 - 2008
N2 - PURPOSE: To identify computed tomographic (CT) findings that distinguish perirenal liposarcomas from exophytic angiomyolipomas. MATERIALS AND METHODS: We identified CT scans of 20 patients (13 women and 7 men; mean age, 63 years) with either perirenal liposarcoma (n = 11) proven at histopathology or large exophytic angiomyolipomas (n = 9) determined by 2-year stability (n = 6) or histopathology (n = 3). Two independent readers unaware of the final diagnoses recorded the presence of the following CT findings: (1) tumoral vessel extending into the renal cortex, (2) tumoral vessel extending into the renal hilum, (3) renal parenchymal defect at the site of tumor contact, (4) intratumoral hemorrhage, (5) nonfat attenuating intratumoral nodules, and (6) calcification. RESULTS: A tumoral vessel extending into the renal cortex was seen only in angiomyolipomas (7 and 6 of 9 patients versus 0 and 0 of 11 liposarcomas for readers 1 and 2, respectively; P < 0.005 for both). A parenchymal defect was more commonly seen in angiomyolipomas (7 and 6 of 9 angiomyolipomas versus 1 and 1 of 11 liposarcomas for readers 1 and 2, respectively; P < 0.05 for both). Calcifications were seen by both readers in 6 of 11 liposarcomas but not in any angiomyolipomas (P < 0.05). The other recorded findings were not useful in distinguishing CT features (P > 0.1 for both readers). CONCLUSIONS: In the evaluation of a fatty perinephric mass at CT, the presence of a tumoral vessel extending into the renal cortex or a renal parenchymal defect at the site of tumor contact strongly favors the diagnosis of exophytic angiomyolipoma, whereas calcifications suggest liposarcoma.
AB - PURPOSE: To identify computed tomographic (CT) findings that distinguish perirenal liposarcomas from exophytic angiomyolipomas. MATERIALS AND METHODS: We identified CT scans of 20 patients (13 women and 7 men; mean age, 63 years) with either perirenal liposarcoma (n = 11) proven at histopathology or large exophytic angiomyolipomas (n = 9) determined by 2-year stability (n = 6) or histopathology (n = 3). Two independent readers unaware of the final diagnoses recorded the presence of the following CT findings: (1) tumoral vessel extending into the renal cortex, (2) tumoral vessel extending into the renal hilum, (3) renal parenchymal defect at the site of tumor contact, (4) intratumoral hemorrhage, (5) nonfat attenuating intratumoral nodules, and (6) calcification. RESULTS: A tumoral vessel extending into the renal cortex was seen only in angiomyolipomas (7 and 6 of 9 patients versus 0 and 0 of 11 liposarcomas for readers 1 and 2, respectively; P < 0.005 for both). A parenchymal defect was more commonly seen in angiomyolipomas (7 and 6 of 9 angiomyolipomas versus 1 and 1 of 11 liposarcomas for readers 1 and 2, respectively; P < 0.05 for both). Calcifications were seen by both readers in 6 of 11 liposarcomas but not in any angiomyolipomas (P < 0.05). The other recorded findings were not useful in distinguishing CT features (P > 0.1 for both readers). CONCLUSIONS: In the evaluation of a fatty perinephric mass at CT, the presence of a tumoral vessel extending into the renal cortex or a renal parenchymal defect at the site of tumor contact strongly favors the diagnosis of exophytic angiomyolipoma, whereas calcifications suggest liposarcoma.
KW - Angiomyolipoma
KW - CT
KW - Kidney
KW - Neoplasms
KW - Retroperitoneal liposarcoma
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U2 - 10.1097/RCT.0b013e3181507534
DO - 10.1097/RCT.0b013e3181507534
M3 - Article
C2 - 18664840
AN - SCOPUS:49949097247
SN - 0363-8715
VL - 32
SP - 548
EP - 552
JO - Journal of Computer Assisted Tomography
JF - Journal of Computer Assisted Tomography
IS - 4
ER -