Histotype differentiation of hypo-echoic renal tumors on CEUS: usefulness of enhancement homogeneity and intensity

Abstract

CEUS homogeneity and TOC ratio are helpful in differential diagnosis of hypo-echoic renal tumor histotypes. Diameter and enhancement homogeneity should be considered when deciding the diagnostic TOC ratio cutoff.

Quantitative assessment of solid renal masses by contrast-enhanced ultrasound with time–intensity curves: how we do it

“…However, the utility of this sign has been contested [47][48][49]. On CEUS, chRCC hypoenhances relative to ccRCC [35,37]. Additionally, although Lu et al state that there was no statistically significant difference in degree of enhancement between pRCC and chRCC, the tumor/cortex PI ratios for chRCC were all greater than for pRCC in their study [37].…”

“…With CEUS, ccRCC enhances earlier and to a greater degree, than normal renal cortex [12,23,[35][36][37]. With regard to the TIC, this is manifested by a shorter RT and TTP, a steeper WIS, and a higher peak intensity, than normal renal cortex.…”

“…On CEUS, pRCCs are hypoenhancing, with a very different wash-in from ccRCC [35,37]. They tend to show a longer RT and TTP, a less steep WIS, and a lower PI, than normal cortex.…”

“…Lu et al evaluated RCC subtypes with CEUS, and for tumors >4 cm in size, a tumor/cortex PI ratio of 108% differentiated ccRCC from other tumors (pRCC, chRCC, and AML together) with sensitivity, specificity, PPV, and NPV of 93%, 75%, 85%, and 88%, respectively [37]. Additionally, the tumor/cortex PI ratio of ccRCC was significantly higher than each of AML, pRCC, and chRCC separately.…”

“…Lu et al showed that ccRCC has a shorter TTP and RT than AML (RT was defined slightly differently on their study, as the time over which contrast increased from 10% to 90% of peak intensity) [38]. Overall enhancement of ccRCC is more commonly heterogeneous than the other subtypes and AML [37].…”