Abstract | OBJECTIVE: The purpose of our study was to evaluate the combination of dynamic contrast-enhanced T1-weighted and double-echo gradient-echo MR imaging to distinguish renal oncocytoma with high T2 signal intensity centrally from renal cell carcinoma (RCC). MATERIALS AND METHODS: Between 2006 and 2011, 63 renal tumors (59 patients) presenting with a high signal intensity (SI) central area on T2-weighted sequences were imaged with dynamic contrast-enhanced sequences, including phases later than 5 minutes after contrast injection, and double-echo chemical-shift sequences were selected from our institutional database. Two experienced radiologists visually assessed presence and distribution of signal enhancement of central areas after injection and measured SI changes on opposed-phase images for calculation of the SI index and tumor-to-spleen ratio. Cutoff values were derived from the receiver operating characteristic (ROC) curve. RESULTS: There were 19 oncocytomas (16 patients), 43 RCCs (42 patients), and one leiomyoma. Complete late enhancement of the central area was observed in 14 oncocytomas (74%) and in five RCCs (12%) (p = 0.05). The combination of complete enhancement and SI index lower than 2% (p = 0.02) or tumor-to-spleen ratio higher than -6% (p = 0.001) provided sensitivity of 36% and 55%, specificity of 95% and 97%, positive predictive value of 67% and 86%, and negative predictive value of 84% and 88%, respectively, for diagnosis of oncocytomas. CONCLUSION: Absence of central area SI inversion or presence of a signal drop on chemical-shift imaging may rule out the diagnosis of oncocytoma.
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Authors | François Cornelis, Anne-Sophie Lasserre, Thomas Tourdias, Colette Deminière, Jean-Marie Ferrière, Yann Le Bras, Nicolas Grenier |
Journal | AJR. American journal of roentgenology
(AJR Am J Roentgenol)
Vol. 200
Issue 4
Pg. 830-8
(Apr 2013)
ISSN: 1546-3141 [Electronic] United States |
PMID | 23521457
(Publication Type: Journal Article)
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Chemical References |
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Topics |
- Adenoma, Oxyphilic
(diagnosis)
- Adult
- Aged
- Aged, 80 and over
- Carcinoma, Renal Cell
(diagnosis)
- Contrast Media
- Diagnosis, Differential
- Female
- Humans
- Kidney Neoplasms
(diagnosis)
- Leiomyoma
(diagnosis)
- Magnetic Resonance Imaging
(methods)
- Male
- Middle Aged
- Predictive Value of Tests
- ROC Curve
- Retrospective Studies
- Sensitivity and Specificity
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