Urothelial and Renal Cancer Pathology

Question 1

What are the most common benign kidney tumors?

Answer 1

• Papillary adenoma
• Oncocytoma
• Angiomyolipoma
  
  • with or without tuberous sclerosis

Question 2

What are the common malignant renal tumors?

Answer 2

• Clear cell renal cell carcinoma (60%)
• Papillary RCC (15%)
• Chromophobe RCC (5-8%)
• Collecting duct carcinoma (<1%)
• Others

Question 3

What is the major histologic difference between papillary adenoma and paillary RCC?

Answer 3

size is the main differentiating factor

Question 4

What are the histological features of renal oncocytomas?

Answer 4

• Mahogany in color
• Benign tumor
• Eosinophilic cytoplasm (mitochondria)
• May have nuclear atypia
• May involve capsule

Question 5

What are the histological findings of renal angiomyolipoma?

Answer 5

• 20% associated with Tuberous Sclerosis (TS complex):
  
  • Kidney lesions: cysts and angiomyolipoma
  • Brian tumors
  • Heart (rhabdomyoma) and eye tumors
  • Skin lesions (such as ash leaf spots)
• 80% sporadic angiomyolipoma
• Histology
  
  • smooth muscle
  • adipose tissue
  • abnormal vessels

Question 6

What are the pathologic features of clear cell, low grade renal carcinomas?

Answer 6

• Clear cell RCCs have clear cells…
• Papillary RCCs have papillae…
• Chromophobe RCCs have cells that “fear” (-phobe) “color” (chromo-)…
• RCCs with sarcomatoid features have cells that look spindle cell sarcoma…
• Collecting duct RCCs similar to collecting ducts…
• Very yellow because loaded with lipid and glycogen

Question 7

Describe the histology of high grade clear cell RCC.

Answer 7

More likely to be high grade tumor, look for nuclear patterns

Question 8

What are the Fuhrman grades for renal cell carcinoma?

Answer 8

• G1 - nucleoli not seen
• G2 - nucleoli high power
• G3 - nucleoli low power
• G4 - Bizarre nuclei

Question 9

What are the pathologic features of low grade papillary RCC?

Answer 9

Tan-yellow, tumor cells and some macrophages, almost never bright yellow

Question 10

What are the pathalogic features of high grade papilloma RCC?

Answer 10

Very uniform, granular appearance because of papillary structure

Question 11

What are the histologic findings of chromophobe RCC?

Answer 11

Tumors don’t stain very well, fine granules that are membrane-bound vesicles

Question 12

What are the pathologic features of sarcomatoid RCC?

Answer 12

• Large tumor, average of 10 cm with:
  
  • normal cortex
  • clear cell component
  • sarcomatoid component
• Large mass (average 10 cm)
• Grossly, flashy white appearance mixed with yellow or brown nodules
• Association with low grade component
• Poor Prognosis
• Specific treatment protocol

Question 13

What are the chromosomal abnormalities of clear cell and papillary RCC?

Answer 13

• Clear cell = -3p
• Papillary = +7, +17, -Y

Question 14

What are the pathological features of urothelial carcinoma of the renal pelvis?

Answer 14

Mass in pelvis, polypoid lesion, fibrovascular core

Question 15

What are the classifications of bladder tumors by pathology?

Answer 15

• Urothelial carcinoma
  
  • Flat
    
    • Carcinoma in situ
    • Invasive
  • Papillary
    
    • Noninvasive
    • Invasive
• Other primary neoplasms
  
  • Squamous cell carcinoma
  • Adenocarcinoma
  • Small cell carcinoma
  • Carcinosarcoma
  • Melanoma
• Secondary neoplasms
  
  • Direct extension
  • Metastasis

Question 16

What are the pathological features of urothelial carcinoma in situ?

Answer 16

• CIS, tumor does not have a lot more cells
• Urothelial cells result
• Not invasive yet
• Simply high N/C ratio
• Can become invasive in short time

Question 17

What are the histological findings of low grade, non-invasive papillary urothelial carcinomas?

Answer 17

Tissue fragments from resection, tumor cells cover a fibrovascular core, similar to urothelial lining with atypia

Question 18

What are the pathologic findings of high grade non invasive papiloma UCa?

Answer 18

Uncommon, papillary configuration, also non invasive

Question 19

What are some markers of urothelial cells?

Answer 19

GATA3 and S100p

Question 20

What are some uncommon tumors of the bladder?

Answer 20

• Adenocarcinoma
• Squamous cell carcinoma
• Benign stromal tumors
• Sarcomas
• Melanoma

Question 21

What are some neuroendocrine tumors of the bladder?

Answer 21

• Small cell carcinoma
• Carcinoid tumor
• Paraganglioma
• Neuroendocrine differentiation of UCa

Question 22

What are some pathologic features of primary adenocarcinoma (enteric type)?

Answer 22

Features similar to colon cance,r want to make sure it is not metastatic colon cancer, patients undergo colonoscopy

Question 23

What are the histologic features of squamous cell carcinoma of the bladder?

Answer 23

Look for keratinization and large, squamous cells

Question 24

What are the pathologic features of UCa with sarcomatoid differentiation (carcinosarcoma)

Answer 24

Tumor cell with a carcinomatous and a sarcomatous component

Question 25

What are the features of metastatic melanoma to the bladder?

Answer 25

Typically have melanocytic features, can be hard to distinguish, but sometimes see pigment, use S100 melanoma marker along with HMB45 marker

Question 26

What are some pathological findings of the following: prostatic adenocarcinoma of the bladder, secondary adenocarcinoma from colon, metastatic adenocarcinoma from breast?

Answer 26

* Prostatic adenocarcinoma stains positive for PSA * Secondary adenocarcinoma from colon looks very similar to adenocarcinoma, and clinical findings are important * Metastatic adenocarcinoma from breast stains positive for mammoglobin