1. Case 3

2. Basic clinical data 51-year-old Caucassian male
Tumor of the kidney 17 x 16 x 12 cm
Widely necrotic (80% of tumorous mass)
Vital part was grey with hemorrhagias on cut section

3. ???

4. Locust vs. Trixalis or Acrida

5. Immunohistochemistry
Positive reactions
AE1-AE3
EMA
Vimentin
Negative reactions
HMB45
S-100
CAM 5.2
Actin S

6. Mucinous tubular and spindle cell carcinoma

7. Synonyms Loopoma RCC with lower-nephron differentiation
Low grade collecting duct RCC
Spindle and cuboidal RCC
Low grade spindle cell RCC

8. Mucinous tubular and spindle cell carcinoma
Age range years
Females are affected more frequently
Usually disclosed by ultrasonographic examination for different reasons
Favourable prognosis- low-grade tumors
Only 2 metastatic cases in the world literature

9. Mucinous tubular and spindle cell carcinoma
Differential diagnostics:
Papillary RCC
Sarcomatoid RCC
Angiomyolipoma
Metastasis of adenocarcinoma