In total,
1,100 patients were diagnosed with a renal mass,
being 153 included in this sample with a unique lesion.
Among these,
108 (70,6 %) were clear cell renal cell RCC,
30 (19,6 %) were papillary RCCs,
and 15 (9,8 %) were chromophobe RCCs.
The baseline characteristics for each of the groups are demonstrated in Table 1.
Table 1: Epidemiology characteristics of all lesions and subgroups.
Objective evaluation
The mean attenuation measurements according to each group are listed in Table 2.
Table 2: Attenuation of renal masses on the basis of histologic subtype.
In corticomedullary phase,
enhancement of clear cell RCCs was significantly greater than that of papillary RCCs (137 HU vs 60 HU,
P = .001),
such as greater than that of chromophobe RCCs (137 HU vs 96 HU,
P = .001).
In nephrographic phase,
the enhancement attenuation of clear cell RCCs was also significantly greater than that of papillary RCCs (117 HU vs 70 HU,
P = .001) such as greater than that of chromophobe RCCs nephrographic (117 HU vs 88 HU,
P = .001).
Enhancement of clear cell RCCs was significantly greater than that of papillary RCCs in the excretory (75 HU vs 59 HU,
P = .001) phase,
such as greater than that of chromophobe RCCs (75 HU vs 60 HU,
P = .015).
Subjective evaluation
Subjective features are listed in Table 3.
Qualitative features that aid the differentiation between clear cell RCCs and papillary RCCs were necrosis (65/108 vs 5/30,
P < .001),
contrast enhancement pattern (P < .001) and washout (82/108 vs 1/30,
P < .001),
and between clear cell RCCs and chromophobe RCCs were necrosis (65/108 vs 3/15,
P = .009),
contrast enhancement pattern (P < .001),
washout (82/108 vs 6/15,
P = .012) and vessels into the lesion (7/108 vs 4/15,
P = .03).
Table 3: Imaging features of renal masses on the basis of histologic subtype.