RENAL PATHOLOGY 4

Question 1

This malignant renal neoplasm is closely resembles a benign neoplasm microscopically. What is the malignant neoplasm?

Answer 1

Chromophobe carcinoma - closely resembles oncocytoma. The two are distinguished by the presence of a perinuclear halo in chromophobe carcinoma (see image attached)

Question 2

Is this a feature of nephroblastoma or neuroblastoma?

elevated urine levels of the metabolites vanillylmandelic acid [VMA] and homovanillic acid [HVA]).

Answer 2

Neuroblastoma

Question 3

most common site for metastasis in RCC

Answer 3

Lungs (cannon ball lesions)

The example shown here reveals multiple, bilateral, rounded soft tissue density masses on the chest x-ray.

Question 4

Cell of origin of this tumor

Answer 4

Papillary RCC - cell of origin is distal convoluted tubules

Question 5

Clinical consequence of invasion of left renal vein by RCC

Answer 5

Left renal vein invasion→ impaired drainage of the left spermatic vein→ left sided varicocele

Question 6

precursor lesions of nephroblastoma

Answer 6

nephrogenic rests

Question 7

Neuroblastoma/ nephroblastoma?

Answer 7

Neuroblastoma

The attached image shows blueberry muffin baby with multiple light bluish subcutaneous nodules over trunk and extremities due to cutaneous metastases from neuroblastoma

Question 8

Clinical significance of renal adenomas

Answer 8

Close resemblance to low grade papillary RCC; potentially malignant

Question 9

Identify this syndrome associated with Wilms tumor:

Wilms tumor, aniridia, genitourinary anomalies, and intellectual disability (retardation)

Answer 9

WAGR

Wilms tumor, aniridia, genitourinary anomalies, and intellectual disability (retardation)

Question 10

Identify the tumor described

This benign renal neoplasm (see attached image) arises form intercalated cells of the collecting duct and

Answer 10

Oncocytoma

Gross image shows: tan or mahogany brown, relatively homogeneous, and usually well encapsulated with a central scar

Question 11

Underlying molecular basis of neuroblastoma

Answer 11

amplification of the N-MYC oncogene

Question 12

Identify this syndrome associated with Wilms tumor:

organomegaly, macroglossia, hemihypertrophy, omphalocele, and adrenal cytomegaly

Loss of maternal imprinting/ uniparental paternal disomy of IGF-2

Localized to WT 2 locus on 11p15.5

Answer 12

Beckwith-Wiedemann syndrome (BWS)

Question 13

most common primary renal tumor of childhood

Answer 13

Wilms Tumor (Nephroblastoma)

Question 14

What is the clinical significance of detecting amplification of the NMYC oncogene in neuroblastoma?

Answer 14

The presence of MYCN amplification “bumps” the tumor to the “high”-risk category, irrespective of age, stage, or histology

Question 15

Most common type of renal cell carcinoma (RCC)

Answer 15

Clear cell

Question 16

See attached microscopic image and identify the tumor

Answer 16

Oncocytoma

Observe the large eosinophilic cells having small, round, benign-appearing nuclei that have large nucleoli, intensely pink cytoplasm due to the abundant mitochondria

Question 17

How does having VHL syndrome lead to tumor and cyst development?

Answer 17

Deletion of VHL gene → impaired ubiquitination and elimination of hypoxia-inducible factor 1α → loss of function → tumor and cyst development

Question 18

What is the reason for the yellow appearance of clear cell carcinoma?

Answer 18

prominent lipid accumulations in tumor cells.

Question 19

Most significant risk factor for renal cell carcinoma

Answer 19

Smoking

Question 20

Identify the tumor described

5 year old, abdominal mass, hematuria

See attached image

Answer 20

Nephroblastoma (Wilms tumor)

Question 21

25-50% cases of angiomyolipomas are associated with this syndrome

Answer 21

Tuberous sclerosis - hypomelanotic (ash leaf) macules, angiofibromas, cardiac rhabdomyomas, Shagreen patches.

Question 22

List 2 poor prognostic features for renal cell carcinoma

Answer 22

Invasion of the renal vein

Sarcomatoid change (histologic)

Question 23

cell of origin of oncocytoma

Answer 23

intercalated cells of collecting ducts

Question 24

most critical determinant of prognosis in Wilms

Answer 24

Anaplastic histology

Question 25

Histopathologic features of angiomyolipoma

Answer 25

mixtures of well-differentiated adipose tissue, smooth muscle and thick-walled vessels

Question 26

See attached microscopic image.

Identify the tumor and the reason for this appearance

Answer 26

Clear cell type of renal cell carcinoma.

Cells appear clear due to prominent lipid accumulations in tumor cells

Description: Individual tumor cells are rounded or polygonal, abundant clear or granular cytoplasm, which contains glycogen and lipids, delicate branching vasculature

Question 27

Cell of origin of clear cell carcinoma

Answer 27

proximal tubular epithelium

Question 28

Identify this paraneoplastic syndrome associated with RCC

hepatic abnormalities with no evidence of hepatic metastases

Elevations of AST, ALT, ALP, and PT , gammaglobulin and bilirubin (any 3 for diagnosis

Secretes hepatotoxins, lysosomal enzymes, IL-6

Answer 28

Stauffer’s Syndrome

Question 29

Identify this syndrome associated with Wilms tumor:

Wilms tumor, Diffuse mesangial sclerosis (early-onset nephrotic syndrome), Dysgenesis of gonads (male pseudohermaphroditism).

Risk of gonadoblastomas

Answer 29

Denys-Drash syndrome

Question 30

4 major paraneoplastic syndromes associated with RCC

Answer 30

1. Hypercalcemia
2. Hypertension
3. Polycythemia
4. Stauffer’s syndrome

Question 31

Why is angimyolipoma clinically significant?

Answer 31

susceptibility to spontaneous hemorrhage

Question 32

What are the IHC markers for this tumor presenting as an abdominal/ flank mass in a child?

Answer 32

This is a neuroblastoma.

Neuron specific enolase, synaptophysin, chromogranin , neurofilament

Question 33

Syndrome associated with both familial and sporadic forms of renal cell carcinoma

Answer 33

§Von Hippel-Lindau (VHL) syndrome

Question 34

Syndromes associated with Wilms tumor

Answer 34

1. WAGR syndrome
2. Denys-Drash syndrome
3. Beckwith-Wiedemann syndrome (BWS)

Question 35

Cell of origin of angiomyolipomas

Answer 35

perivascular epithelioid cell (PEC)

Question 36

Risk factors for this tumor?

Answer 36

This is urothelial carcinoma.

smoking (most common), aromatic amines (aniline dyes), and cyclophosphamide

Question 37

Most cases of Wilms tumor are sporadic or familial?

Answer 37

90% are sporadic

Question 38

Neuroblastoma/ nephroblastoma?

Answer 38

small, primitive-appearing cells with dark nuclei, scant cytoplasm, and poorly defined cell borders and Homer-Wright pseudorosettes (tumor cells concentrically arranged about a central space filled with neuropil)

This is a neuroblastoma

Question 39

Microscopic features of Wilms tumor

Answer 39

Blastemal – sheets of small blue cells

Stromal - spindle cells with smooth muscle /fibroblast differentiation

Epithelial- abortive tubules or glomeruli

Question 40

Constituents of VHL syndrome

Answer 40

Remember HIPPEL

Hemangioblastoma

Increased risk of renal cell carcinoma

Pheochromocytoma

Pancreatic lesions (cysts, cystadenomas , and neuroendocrine tumors )

Eye Lesions (retinal angiomas or hemangioblastomas)

Question 41

Cell of origin of neuroblastoma

Answer 41

neural crest origin

Question 42

Significance of identifying TP53 mutations in Wilms tumor

Answer 42

TP53 mutations are associated with :

an especially poor prognosis

Relative unresponsiveness to cytotoxic chemotherapy.

distinctive anaplastic histologic appearance

Question 43

significance of identifying nephrogenic rests

Answer 43

patients are at an increased risk of developing Wilms tumors in the contralateral kidney and require frequent and regular surveillance

Question 44

Most common presenting clinical feature for this tumor

Answer 44

Hematuria