Renal Pathology V

Question 1

How common are congenital kidney abnormalities?

Answer 1

Common - 10%

Question 2

What does the metanephric blastema become?

Answer 2

Nephrons

Question 3

What does the ureteric bud become?

Answer 3

Collecting Duct System

Question 4

Horseshoe Kidneys

Answer 4

Fused kidneys

Question 5

Ectopic

Answer 5

Abnormal location

Question 6

What is renal dysplasia?

Answer 6

NOT related to neoplasia but developmental abnormality.

Question 7

Cystic Renal Dysplasia

Answer 7

Abnormality in metanephric differentiation - persistence of immature elements: undifferentiated mesenchyme, cartilage, immature collecting tubules, abnormal lobar organization

Question 8

What do the gross kidneys look like in cystic renal dysplasia?

Answer 8

Grossly kidneys enlarged, irregular shape, “bunch

of grapes”

Question 9

What other organ development can cystic renal dysplasia impact?

Answer 9

Lung - agenesis/bilateral dysplasia

Question 10

What is the incidence of Childhood Autosomal Recessive Polycystic Kidney Disease?

Answer 10

Rare - 1 in 50000

Question 11

What are the findings with Childhood Autosomal Recessive Polycystic Kidney Disease?

Answer 11

• Cross-section–sponge-like appearance
• Saccular dilatation of collecting tubules
• Liver: cysts+portal fibrosis+proliferation of portal bile ducts → congenital hepatic fibrosis

Question 12

What are the findings with Adult Polycystic Kidney Disease (APKD)?

Answer 12

Bilateral, reniform shape, enlarged, mass of cysts, functioning nephrons dispersed between the cysts, hepatic cysts

Question 13

What is the inheritance pattern of APKD?

Answer 13

Autosomal Dominant

Question 14

Of the cystic diseases, which ones are bilateral?

Answer 14

ARPKD and APKD are bilateral

Dysplasia can be unilateral or bilateral

Question 15

Of the cystic diseases, which ones have reniform shape?

Answer 15

ARPKD and APKD

Question 16

Of the cystic diseases, which ones have ureter abnormalities?

Answer 16

Dysplasia

Question 17

Of the cystic diseases, which ones have liver abnormalities?

Answer 17

ARPKD and APKD

Question 18

What is the basic assumption of renal tumors?

Answer 18

Malignancy

Question 19

What are the benign kidney tumors?

Answer 19

• Oncocytoma

* Angiomyolipoma

Question 20

What is the origin of an oncocytoma?

Answer 20

Distal Nephron

Question 21

What is the makeup of an angiomyolipoma?

Answer 21

Vessels/smooth muscle/fat

Question 22

What is the triad of renal cell carcinoma presentation?

Answer 22

Costovertebral pain, mass, hematuria

Question 23

What is the pathogenesis of a clear RCC?

Answer 23

von Hippel-Lindau, tumor suppressor gene is lost. Loss of VHL gene results in accumulation of the transcription factor HIF-1α (hypoxia inducible factor - 1α) and over-expression of HIF-1α target genes which facilitate cellular adaptation to tissue hypoxia

Question 24

What is the control of HIF-1alpha by VHL?

Answer 24

Under normoxic conditions VHL ubiquitinates HIF-1a, leading to ubiquitin- mediated proteolysis and degradation by the proteasome

Question 25

What is the function of HIF-1α in tumor cells?

Answer 25

In hypoxic cells, such as those found in tumors, HIF-1α ultimately initiates the transcription of hypoxia-induced genes, including those which promote
– cell survival under anaerobic conditions
– angiogenesis
– metastasis

Question 26

What is the main treatment for RCC?

Answer 26

Surgery

Question 27

What is mTOR?

Answer 27

mTOR is an intracellular serine/threonine kinase in the PI3K/Akt signaling pathway.

• mTOR activation promotes
– Cell growth and proliferation
– Angiogenesis
– Cancer cell metabolism through increased nutrient uptake and utilization

Question 28

von Hippel-Lindau (VHL) Syndrome

Answer 28

• tumors with high vascularity + clear cells
• hemangioblastoma (central nervous system/cerebellum/spine)
• angiomas of the retina
• pheochromocytomas

Question 29

What is the most common type of RCC?

Answer 29

Clear RCC

Question 30

Papillary RCC

Answer 30

• better prognosis than clear cell RCC
• papillary architecture
• hereditary (familial) - multiple bilateral tumors with papillary histology

Question 31

Chromophobe RCC

Answer 31

• Hypodiploidy - multiple chromosomal losses
• Distal nephron
• Prominent cell membrane “vegetable-like”
• Better prognosis in the absence of sarcomatoid component

Question 32

Sarcomatoid RCC

Answer 32

• not a distinct type but rather indicative of de-differentiation
• worse prognosis, regardless of the original tumor morphology

Question 33

Collecting Duct Carcinoma

Answer 33

• Collecting duct origin
• Chromosomal losses
• Very aggressive

Question 34

Urothelial Carcinoma

Answer 34

• renal pelvis, ureter, frequently also concomitant urinary bladder tumor
• hematuria
• analgesic nephropathy = risk factor

Question 35

Wilm’s Tumor Typical Patient

Answer 35

Most common pediatric kidney tumor

Question 36

What is the treatment for Wilm’s tumor?

Answer 36

Chemotherapy. Prognosis is good as it is highly chemosensitive.

Question 37

During a radiologic workup for gall bladder stones, a 65 yo male was found to have a 5 cm mass in his right kidney.

a. This is most likely oncocytoma
b. This is a benign tumor
c. Chemotherapy is effective
d. Surgery consultation should be scheduled
e. Tumor’s morphology shows abortive glomeruli/tubules and stroma

Answer 37

d. Surgery consultation should be scheduled

Question 38

A 2 yo boy is brought to pediatrician because his mother palpated “a bulging mass” while bathing him. What best applies to the case?

a. This tumor most likely is composed of clear cells
b. This tumor typically shows loss of short arm of chromosome 3
c. This tumors is most likely highly chemoresistant
d. This tumor is chemosensitive
e. Tumor morphology will show immature tubules and cartilage

Answer 38

d. This tumor is chemosensitive

Question 39

An infant is diagnosed with an enlarged left kidney – shown with “bunch of grapes” look. Most likely:

a. This lesion will respond to chemotherapy
b. This is a premalignant lesion
c. This is a congenital disorder and genetic testing is indicated
d. Kidney parenchyma shows persistence of immature elements
e. Kidney sections show blastema, tubules and stroma

Answer 39

d. Kidney parenchyma shows persistence of immature elements