Table 2 Comparison of clinicopathologic characteristics of papillary renal neoplasm with reverse polarity with type I and type II papillary renal cell carcinoma
PRNRP (n = 11) | type I PRCC (n = 16) | type II PRCC(n = 9) | PRNRP vs type I PRCC | PRNRP vs type II PRCC | type I PRCC vs type II PRCC | |
|---|---|---|---|---|---|---|
Gender (M: F) | 1.7:1 | 3:1 | 2:1 | 0.675 | 1.000 | 0.673 |
Age (year) | 26–70 (mean 58) | 30–74 (mean 57) | 30–76 (mean 56) | 0.957 | 0.943 | 0.996 |
Diameter (cm) | 0.8 ~ 6 (2.8) | 2.5 ~ 12 (5.7) | 2.5 ~ 6 (4.8) | 0.004 | 0.099 | 0.612 |
Tumor cells | Single-layered, eosinophilic | Single-layered, basophilic | Stratified, eosinophilic | — | — | — |
Inverted nuclei | 11/11 | 0/16 | 0/9 | < 0.001 | < 0.001 | 1.000 |
Intracellular hemosiderin | 6/11 (few cells) | 7/16 | 0/9 | 0.704 | 0.014 | 0.027 |
Foamy macrophages in stroma | 1/11 | 11/16 | 4/9 | 0.005 | 0.127 | 0.397 |
WHO/ISUP nuclear grade (high vs. low)a | Grade 1: 10 Grade 2: 1 | Grade 1: 2 Grade 2: 9 Grade 3: 5 | Grade 2: 1 Grade 3: 6 Grade 4: 2 | < 0.001 | < 0.001 | 0.011 |
Necrosis | 5/11 | 10/16 | 8/9 | 0.452 | 0.070 | 0.355 |
Infiltrative growth | 6/11 | 7/16 | 6/9 | 0.704 | 0.670 | 0.411 |
Microvascular invasion | 0/11 | 1/16 | 4/9 | 1.000 | 0.026 | 0.040 |
Sarcomatoid differentiation | 0/11 | 1/16 | 0/9 | 1.000 | 1.000 | 1.000 |
Stage (early-stage vs. advanced-stage)b | Stage I: 11 | Stage I: 10 Stage II: 3 Stage III: 3 | Stage I: 8 Stage IV:1 | 0.248 | 0.450 | 1.000 |