deck_5150580 Flashcards
What are oncocytomas?
benign tumors from the intercalated cells of the collecting ducts
How common are oncocytomas?
represent less than 10+ of renal tumorsno clinical symptoms
What chromosomal causes are associated with oncocytomas?
loss of chrom 1, 14, and Y
T or F. Oncocytomas are more common in men
T.
Description of oncocytomas
well-circumscribed tumor with a central scar
What are the most common primary neoplasms in adults?
Clear cell carcinoma (70%)Papillary carcinoma (10%)Chromophobe carcinoma (5%)Oncocytoma (5%)Others (urothelial, squamous, 10%)
One thing that can help differentiate kidney tumors is location. Where do urothelial and squamous tumors tend to be?Test question
near the renal pelvis while the others are at the poles of the kidney
Usually the first sign of a kidney tumor is what?
painful hematuria (in elm’s it might actually be palpation of the mass)most kidney tumors have to get large before they cause symptoms
Renal carcinomas tend to spread via what routes?
either through Gerota’s fascia or into the renal vein and up through the IVC
What are the types of renal cell carcinoma?
-clear cell (most common)-papillary-chromophobe
What are renal cell carcinomas derived from?
renal tubular epithelium located in cortex (polar)
What patient population is common for renal cell carcinoma?
men in 60-70s
What are the risk factors for renal cell carcinoma?
-*smokers (same for bladder cancer), -hypertensive or obese patients, -occupational exposure to cadmium,-acquired polycystic disease in chronic dialysis patients
Are clear cell carcinomas sporadic or familial?
Most are sporadic, however familial forms do exist as those with loss of VHL (autosomal dominant, chromosome 3)
What does loss of VHL cause?
Without VHL, HIFs are stabilized. HIFs are transcription factors that contribute to carcinogenesis by stimulating the expression of vascular endothelial growth factor (VEGF), an important angiogenic factor
What is the most important prognostic feature of renal cell carcinoma?
Clinical stage…after that nuclear grade (Fuhrman)
Why are renal cell carcinomas yellow grossly?
cells are filled with lipids
How do papillary renal cell carcinomas present?
frequently multifocal and bilateral and appear as early-stage tumors
How can papillary renal cell carcinomas be distinguished from papillary adenomas?
size greater than 5 mm suggests papillary renal cell carcinoma
Are papillary RCCs sporadic or hereditary?
can be either
What are some potential causes of hereditary papillary RCC?
Chromosome 7 alterations that increase dosage of the MET proto-oncogene seems to spur abnormal growth in the proximal tubular epithelial cell precursors of papillary carcinomas
What has to be present to be a true papillary lesion?
a papillary fibrovascular core
What do chromophobe carcinomas arise from?
Arise from intercalated cells of collecting ductsNo specific genetic signature, lots of different losses
Prognosis for chromophobe carcinomas?
Good prognosis - Same behavior as clear cell when stratified by grade/stageTypical Fuhrman grading may NOT have prognostic significance
Chromophobe carcinomas are positive for what?
Positive for Hale’s colloidal iron stain (negative in oncocytomas)
Chromophobe gross descriptor
No central scar
What are the types of urothelial carcinomas?
-papillary (more granular and 3D)-flat (harder to diagnose)
What is Wilm’s Tumor?
An embryonal pediatric tumor of the kidney
When does Wilm’s Tumor present typically? Prognosis?
The peak incidence of Wilms tumor is between the second and fifth year of life (95% of kidney cancer in children).Post therapy 5 yr survival 90%
What causes Wilm’s Tumor?
Defects in WT1 gene chromosome 11There can be familial germline mutations (WAGR syndrome; Denys-Drash syndrome), but most Wilms tumors arise from acquired mutations
Can you biopsy Wilm’s Tumor?
No, problems with seeding potential
What else is Wilm’s tumor associated with?
Beckwith Wiedemann syndrome- one side of the body is a little larger than the other
The presence of anaplasia with Wilm’s tumor correlates with what?
The presence of acquired TP53 mutations, and the emergence of resistance to chemotherapy.
Microscopically Wilm’s tumors composed of a mixture of what cellular elements?
-blastemal, -stromal, and -epithelial
What are Angiomyolipoma’s associated with?
Patients with Tuberous Sclerosis (TSC1/2 mutation encoding hamerin and tuberin)
