The Urinary Tract: Tumors of The Urinary Tract Flashcards
What is autosomal dominant polycystic kidney disease? (ADPKD)
A group of congenital diseases that are characterized by numerous cysts within the renal parenchyma
What is the epidemiology of ADPKD?
1 in 500 to 1000 individuals
What is the pathogenesis of ADPKD?
Mutations in the polycystic kidney disease 1 gene (PKD1/polycystin-1) on the short arm of chromosome 16 (85%)
OR
Mutations in PKD2 (15%)
–> ALtered mechanosensation by tubular cilia and altered calcium flux –> Altered tubular epithelial growth and differentiation –> Abnormal extracellular matrix, cell proliferation, and fluid secretion –> CYST, glomerular vascular damage and interstitial inflammation/fibrosis
What is the morphology of ADPKD? (3)
- Bilaterally enlarged kidneys (each weighs up to 4.5kg)
- The external contours of the kidneys are distorted by numerous cysts (up to 5cm in diameter)
- The cysts are filled with fluid, which may be clear, turbid or hemorrhagic
What is ARPKD?
Autosomal recessive polycystic kidney disease –> affects children
Rare
What is ARPKD characterized by?
Cystic transformation of collecting ducts
What is the pathogenesis of ARPKD?
Mutation in the PKHD1 gene (coding for a putative membrane receptor protein called fibrocystin)
What is the morphology of ARPKD kidneys?
Numerous small cysts in the cortex and he medulla
Songe like appearance
What is ARPKD associated with?
Associated with congenital hepatic fibrosis (leads to portal hypertension) and hepatic cysts
The mutation in PKHD1
Where is renal cell carcinoma derived from?
Renal tubular epithelium (predominantly in the cortex)
What is the epidemiology of Renal cell carcinoma?
Most common malignant tumor of the kidneys
Accounts for 2 to 3% of all cancers in adults
What is the age population target of RCC?
60 to 70s
What is the male to female ration of RCC?
2:1
What are the risk factors of RCC? (5)
- Smoking
- Obesity and hypertension
- Occupational exposure
- Acquired polycystic disease as a complication of chronic dialysis
- Genetic factors
What kind of occupational exposure leads to RCC?
Exposure to candium
What are the classifications of renal cell carcinomas? (3)
3 main types:
1. Clear cell carcinoma
2. Papillary renal cell carcinoma
3. Chromophobe renal carcinoma
What is the most common subtype of renal cell carcinomas?
Clear cell carcinoma –> 65% of RCC
What is the pathogenesis of Clear cell carcinomas?
Sporadic or familial forms
What is the sporadic pathogenesis of Clear cell carcinomas?
Adult males (average age is 60) as a single tumor in the upper pole of the kideny
What is the major risk factor of sporadic tumors in clear cell carcinoma?
Smoking
Who do familial clear cell carcinomas of RCC affect
Arise in younger adults and are often bilateral
What disease is the familial clear cell carcinoma associated with?
Von Hippel-Lindau (VHL) dsease
What is the pathogenesis of familial clear cell carcinoma?
- Individuals with VHL disease
- Inherit a germline mutation of the VHL gene on chromosomal band 3p25 and lose the second allele by somatic mutation
- Increased IGF-1 or degradation of HIFs
- Promotes growth or stimulation of the expression of VEGF and PDGF
- Proliferation of RCC
What % of RCC is Papillary renal cell carcinomas?
Accounts for 10 to 15% of RCC
What are Papillary renal cell carcinomas like?
- Shows papillary pattern
- Multifocal and bilateral and appear as early-stage tumors
- Sporadic or familial forms
What is the pathogenesis of papillary renal cell cracinomas?
- Duplication of chromosome 7 or Activating mutations of MET in germline
- Overexpression of MET gene
- Abnormal growth in the proximal tubular epithelial cell precursors of the papillary carcinomas
What % of RCC is Chromophobe renal carcinomas?
5%
Where does chromophobe renal carcinoma arise from?
Intercalated cells of collecting ducts
What is the pathogenesis of Chromophobe renal carcinomas?
Multiple losses of entire chromosomes: 1, 2, 6, 10, 13, 17 & 21)
What is the gross morphology of clear cell carcinomas? (2)
- Solitary and large (3 to 15cm)
- Arise anywhere in the cortex
What is the cut surface of clear cell carcinomas? (2)
- Yellow to orange to Gary-white, with prominent areas of cystic softening or hemorrhage
- The margins of the tumor are well defined
What is the range of clear cell carcinomas? Examples? (4)
Range from low grade to high grade:
1. Tumor cells may extend to calyces, pelvis or ureter,
2. May invade renal vein and grow within the vessels
3. Extending as far as the inferior vena cava and into the right side of the heart
4. Direct invasion into the perinephric fat and adrenal gland