Renal Neoplasia - Pathoma

Question 1

What is an Angiomyolipoma?

Answer 1

• Hamartoma composed of blood vessels, smooth muscle, and adipose tissue
  
  • Angio = blood vessel
  • myo = muscle
  • lipo = fat (adipose tissue)

Question 2

In what cases is there an increased frequency of Angiomyolipomas?

Answer 2

Tuberous sclerosis

Question 3

What type of Renal neoplasia is a malignant epithelial tumor that arises from the kidney tubules?

Answer 3

Renal Cell Carcinoma

Question 4

What is the classic presentation of Renal Cell Carcinoma?

Answer 4

• Triad:
  
  • Hematuria
  • Palpable mass
  • Flank pain
• Also common:
  
  • fever
  • weight loss
  • paraneoplastic syndrome (EPO, renin, parathyroid horomone related peptide, ACTH)

Question 5

How does a varicocele form in the case of Renal Cell Carcinoma?

Answer 5

• Left-side only
  
  • carcinoma obstructs gonadal vein draining into left renal vein
  • blood backs up => varicocele
• Not on right side
  
  • gonadal veing drains directly into inferior vena cava

Question 6

Which type of renal neoplasm reveals a yellow mass on gross exam and clear cytoplasm microscopically?

Answer 6

Renal Cell Carcinoma

(called clear cell type)

Question 7

The pathogenesis of Renal Cell Carcinoma involves the loss of what gene?

Answer 7

VHL (3p) = tumor suppressor gene

Question 8

What happens when you lose the expression of VHL in Renal Cell Carcinoma?

Answer 8

• Increased IGF-3 (insulin-like growth factor)
  
  • promotes growth
• Increased HIF transcription factor
  
  • increases VEGF and PDGF (platelet-derived growth factor)

Question 9

What are the two pathways in the development of Renal Cell Carcinoma?

Answer 9

• Sporadic Pathway
  
  • single tumor in upper pole of kidney
  • usually in smoker
• Hereditary
  
  • tumors that arise in younger patients
  • multiple tumors and bilateral

***Both involve loss of VHL expression!

Question 10

What is one autosomal dominant hereditary disorder that is associated with the inactivation of the VHL gene?

Answer 10

Von-Hippel Lindau Disease

Question 11

Patients with Von Hippel-Lindau are at increased risk to develop what?

Answer 11

• Hemangioblastoma of the cerebellum
• Renal Cell Carcinoma

Question 12

What is staging of Renal Cell Carcinoma based on?

Answer 12

• T = based on tumor size and involvement of renal vein
  
  • increases the risk of hematogenous spread to the lungs and bones
• N = spread to retroperitoneal lymph nodes

Question 13

What do you call a malignant tumor of the kidney comprised of blastema, primitive glomeruli and tubules, and stromal cells?

Answer 13

Wilms Tumor

Question 14

What is the most common malignant renal tumor in children?

Answer 14

Wilms Tumor

(average age = 3 yoa)

Question 15

What is the classic presentation of Wilms Tumor?

Answer 15

• Large, unilateral flank mass
• Hematuria
• HTN
  
  • due to renin secretion

Question 16

What mutation is Wilms Tumor associated with?

Answer 16

WT1 mutations

(especially syndromic cases)

Question 17

What is the WAGR Syndrome?

Answer 17

• W = Wilm’s tumor
• A = Aniridia
• G = Genital abnormalities
• R = Mental and motor Retardation

Question 18

What WT1 mutation associated syndrome consists of Wilms Tumor, neonatal hypoglycemia, muscular hemihypertrophy, and organomegaly (e.g. tongue)?

Answer 18

Beckwith-Wiedmann Syndrome