**2.11 Clear cell**

Clear cell UC is a very rare variant of UC characterized by tumour cells with glycogen-rich cytoplasm (**Figure 10**). It is crucial to do the correct differential diagnosis among clear cell UC, clear cell adenocarcinoma of the bladder, metastatic clear cell renal cell carcinoma or clear cell carcinoma of the female genital tract [28].

Only a few case reports are available for this rare histologic variant. The evidence suggests a high progression rate to muscle-invasive and metastatic BC, and although treatment strategy is poorly defined, an aggressive approach with early RC is advocated [40].

#### **Figure 9.**

*It contains both carcinoma as well as sarcomatous areas usually with high-grade urothelial carcinoma on the surface and a high-grade undifferentiated sarcoma underneath in the lamina propria (HE × 100).*

#### **Figure 10.**

*Clear cell variant of urothelial carcinoma consists of abundant clear cytoplasm due to glycogen content and it is characterized by large nests of tumour cells with high- grade nuclear atypia and clear cytoplasm (HE* **×** *200).*
