Tumors of Urinary Tract Flashcards
What is a renal papillary adenoma / where is it located and how does it look under the microscope?
Benign tumor of renal tubular epithelium invariably located in the renal cortex (also called renal cortical adenoma)
Appears as cytologically bland epithelial cells composed of branching papillary structures
How do renal cortical adenomas present clinically, and what is the diagnosis restricted to in terms of size?
Typically an incidental finding on kidney resection for other findings or autopsy
Low grade lesion which must be 5mm or less in size
What cells are an oncocytoma comprised of? Is it benign or malignant?
Comprised of oncocytes - renal collecting duct intercalated epithelial cells which stain very eosinophilically due to abundant mitochondria and lack of perinuclear clearing
It is a benign tumor
How does oncocytoma appear grossly? What will be the patient’s presenting symptoms?
Usually asympatomatic, but may have hematuria / flank pain
Appear as a sometimes-large, well circumscribed brown mass with a central white scar
What is the most common primary malignancy of the kidney? What is the cell of origin? How old / what sex are patients who generally present with it?
Renal cell carcinoma (RCC)
Cell of origin is proximal renal tubular epithelial cells
Patients are generally older males (i.e. 60)
What are the three most common types of RCC? Which have the best prognosis?
- Clear cell RCC
- Papillary RCC
- Chromophobe RCC
Papillary / chromophobe better prognosis than clear cell
What are the major risk factors for sporadic RCCs?
Cigarette smoking and obesity
Long-term dialysis with acquired cystic kidney disease
Hypertension
Occupational Exposures - cadmium, organic solvents (trichloroethylene in plastics), drugs like cyclophosphamide and phenacetin
What hereditary condition is most commonly associated with development of RCC and what chromosome is the gene found on?
Von Hippel Lindau (3 letters)
Autosomal dominant - tumor suppression gene on chromosome 3 (3 letters = RCC) called VHL
What is the function of VHL / how do things go awry?
Tumor suppressor gene which inhibits hypoxia inducible factor
-> defect leads to increased transcription of HIF -> increased transcription of VEGF and PDGF
What are the most common benign / malignant tumors associated with von Hippel Lindau?
Hemangioblastomas - especially cerebellum
Pheochromocytomas
Bilateral renal cell carcinomas, happening at younger ages
What inherited genetic disorder is associated with development of papillary RCC? What gene product has gone awry?
hereditary papillary renal cell carcinoma (HPRCC)
Autosomal dominant, due to mutation in a tyrosine kinase of MET proto-oncogene on chromosome 7
-> chromosome 7 associated with papillary tumors
What renal tumor is associated with hereditary leiomyomatosis renal cell carcinoma / how can these patients be differentiated from HPRCC?
Papillary renal cell carcinoma
These patients will develop cutaneous leiomyomas (smooth muscle tumors), even in the uterus in females
HPRCC patients will have no other clinical manifestations than renal tumors
What is Birt-Hogg-Dube syndrome associated with?
Autosomal dominant tumor suppressor loss
- Fibrofolliculomas -> fibroblast tumors of hair follicles with skin tags
- Pneumothoraces - due to development of pulmonary blebs / cysts
- Increased risk for RCCs (especially chromophobe), oncocytomas
What is the classic triad of RCC?
Hematuria, flank pain, and palpable mass
What paraneoplastic syndromes are most commonly associated with RCC?
- Polycythemia - due to production of EPO
- Cushing syndrome - due to ACTH secretion
- Hypercalcemia - PTHrP
- Hypertension - increased renin production
What is Stauffer syndrome? What lab test will be abnormal?
Non metastatic liver dysfunction paraneoplastic syndrome caused by RCC
-> due to release of IL-6
Liver function tests will be abnormal
Where does RCC commonly metastasize to? What can a left-sided RCC cause which a right-sided cannot?
Moves through IVC -> commonly goes to lung and bone
Left-sided = varicocele, due to compression of renal vein, which drains the testicular vein on the left but not the right
How does a clear cell renal carcinoma appear grossly?
Large tumors which are most often golden-yellow due to high lipid content
Tumors are often cystic, with frequent necrosis
Why do the cells appear clear in renal cell RCC? What will be the other impressive feature of it microscopically?
Cells are clear due to high amounts of glyogen and lipid which get washed out in staining
Impressive sinusoidal vascular pattern
How is RCC staged?
Stage 1 - confined to kidney, less than 7 cm
Stage 2 - confined to kined, greater than 7 cm
Stage 3 - invaded into perinephric fat but not broken capsule (Gerota’s fascia)
Stage 4 - Invasion through capsule (including ipsilateral adrenal gland), or any distant metastases
What is an angiomyolipoma? How does it present if acute?
Hamartoma with “Triphasic” morphology - blood vessels, smooth muscle, fat
Presents with hemorrhage (due to blood vessel, in sporadic form) or renal failure (genetic form)
How does the presentation of angiomyolipoma differ between sporadic and genetic/hereditary-predisposed individuals?
Sporadic - usually solitary lesion -> usually presents with hemorrhage
Hereditary - happens in Tuberous sclerosis (disease of hamartomas) -> usually multiple and bilateral, which is why it causes renal failure
What is the most common pediatric renal neoplasm? What cells is it comprised of?
Wilms tumor
Triphasic - Comprised of blastemal (primitive mesenchyme), epithelial (primitive tubules and glomeruli), and developed mesenchymal (stromal cells)
Are the majority of Wilms tumors sporadic or inherited? What chromosome is at fault / why?
Vast majority are sporadic, but there are well known associated clinical syndromes
-> chromosome 11 in all these syndromes, which has WT1 and WT2 tumor suppressor genes
