Magnetic Resonance Imaging as a Biomarker for Renal Cell Carcinoma

Table 1

Selected review of the literature on diffusion-weighted MRI.

Authors	Year	Sample size	values (s/mm^2)	Main findings
Sandrasegaran et al. [40]	2010	59 lesions; (i) 20 benign; (ii) 17 ccRCCs, 5 pRCCs, and 1 chRCC; (iii) 2 TCCs	0, 400, and 800	ADCs of malignant tumors are lower than those of benign tumors.; ADCs of high-grade ccRCC are lower than those of low-grade ccRCC.
Paudyal et al. [41]	2010	47 lesions; (i) 25 ccRCCs; (ii) 6 pRCCs; (iii) 1 chRCC; (iv) 15 TCCs	0, 300, and 1000	Significant differences exist in ADCs between clear-cell RCCs and non-clear-cell RCCs, between RCCs and TCCs, and between positive and negative metastatic lesions.
Wang et al. [42]	2010	85 lesions; (i) 49 ccRCCs; (ii) 22 pRCCs; (iii) 14 chRCCs	0, 500, and 800	Mean ADC (acquired with 800 sec/mm^2) allows differentiation of RCC subtypes with 95.9% sensitivity and 94.4% specificity, whereas mean ADCs (acquired with 500 sec/mm^2) cannot differentiate between pRCC and chRCC.
Tanaka et al. [43]	2011	41 lesions; (i) 36 ccRCCs; (ii) 5 MFAMLs	0, 800	Clear-cell RCC exhibits more heterogeneous signal on ADC map than MFAML.
Taouli et al. [44]	2009	109 lesions; (i) 81 benign; (ii) 28 RCCs	0, 400, and 800	Mean ADC is able to differentiate RCC from benign lesions and papillary RCC from nonpapillary RCCs.; DCE MRI was more accurate than ADC, but the combination of the two had the best specificity.
Chandarana et al. [45]	2012	26 lesions; (i) 14 ccRCCs; (ii) 5 chRCCs; (iii) 3 cystic RCCs	0, 50, 100, 150, 250, 400, 600, and 800	The combination of perfusion fraction and tissue diffusivity can diagnose pRCC and cystic RCC with 100% accuracy and ccRCC and chRCC with 86.5% accuracy.
Notohamiprodjo et al. [46]	2013	18 lesions; (i) 14 ccRCCs; (ii) 4 pRCCs	0, 500	ADC shows moderate correlation with the extracellular volume but is not related to tumor oxygenation or perfusion.
Desar et al. [47]	2011	10 lesions	50, 300, and 600	A significant increase at day 3, followed by a decrease at day 10 in ADC, after sunitinib is applied to patients with RCC, indicating a change in cellularity, edema, and necrosis.

ccRCC: clear-cell renal cell carcinoma; pRCC: papillary renal cell carcinoma; chRCC: chromophobe renal cell carcinoma; TCC: transitional cell carcinoma; MFAML: minimal fat angiomyolipoma.