Clear Cell Renal Cell Carcinoma

Watchlist
Retrieved
2021-01-18
Source
Trials
Genes
Drugs

The Clear Cell Renal Cell Carcinoma (CCRCC) is a type of renal cell carcinoma.

Genetics

Cytogenetics

  • Alterations of chromosome 3p segments occurs in 70 – 90% of CCRCCs
  • Inactivation of von Hippel-Lindau disease (VHL) gene by gene mutation and promoter hypermethylation
  • Gain of chromosome 5q
  • Loss of chromosomes 8p, 9p, and 14q

Molecular genetics

Several frequently mutated genes were discovered in CCRCC: VHL, KDM6A/UTX, SETD2, KDM5C/JARID1C and MLL2. PBRM1 is also commonly mutated in CCRCC.

Histogenesis

CCRCC is derived from the proximal convoluted tubule.

Microscopy

Generally, the cells have a clear cytoplasm, are surrounded by a distinct cell membrane and contain round and uniform nuclei.

Microscopically, CCRCCs are graded by the ISUP/WHO as follows:

  • Grade 1: Inconspicuous and basophilic nucleoli at ×400 magnification
  • Grade 2: Clearly visible and eosinophilic nucleoli at ×400 magnification
  • Grade 3: Clearly visible nucleoli at ×100 magnification
  • Grade 4: Extreme pleomorphism or rhabdoid and/or sarcomatoid morphology

Epidemiology

  • Most commonly affects male patients in their sixties and seventies.
  • Majority of CCRCC arise sporadically.
  • Only 2 – 4% of the cases presenting as part of an inherited cancer syndrome, such as von Hippel-Lindau syndrome.

Images