Lower Urinary Tract Carcinoma - Pathoma

Question 1

What are the three types of cancer that can arise in the lower urinary tract?

Answer 1

1. Urothelial carcinoma
2. Squamous cell
3. Adenocarcinoma

Question 2

What is the most common type of lower urinary tract cancer?

Answer 2

Urothelial Carcinoma

(usually arises in the bladder)

Question 3

What is Urothelial Carcinoma?

Answer 3

• Malignant tumor arising from the urothelial lining of renal pelvis, ureter, bladder, or urethra
  
  • usually arises in the bladder

Question 4

What is the #1 risk factor of Urothelial Carcinoma?

Answer 4

Cigarette Smoke

(particularly polycyclic aromatic hydrocarbons)

Question 5

What are the other risk factors for Urothelial Carcinoma?

Answer 5

• Naphthylamine
  
  • (carcinogen in cigarette smoke)
• Azo dyes
• Long term cyclophosphamide or phenacetin

Question 6

What is the classic presentation of Urothelial Carcinoma?

Answer 6

• Painless hematuria
  
  • generally seen in older adults

Question 7

What are the two pathways in which Urothelial Carcinoma arises?

Answer 7

• Flat
  
  • starts as high-grade thelilal carcinoma → flat lesions → progresses to invading tumor
  • associated with early p53 mutations
• Papillary
  
  • fibrovascular core with blood vessel running through it
  • tumor starts as low grade → progresses to high grade → then invades

Question 8

What does the term “Field Defect” mean?

Answer 8

• Entire urothelial lining has been mutated
  
  • exposure to carcinogens throughout lower urinary tract over a long period of time
  • mutations present throughout, only a matter of time before multiple tumors develop
    
    • often have recurrence

Question 9

Why is squamous cell carcinoma of the lower urinary tract interesting?

Answer 9

• Lower urinary tract does not normally have any squamous cell epithelium
  
  • must develop squamous metaplasia
  • urothelial cells → dysplasia → squamous cell

Question 10

What area of the lower urinary tract does Squamous Cell Carcinoma usually involve?

Answer 10

Bladder

Question 11

What are the three key risk factors for Squamous Cell Carcinoma?

Answer 11

1. Chronic cystitis
2. Schistosoma hematobium
3. Long-standing nephrolithiasis

Question 12

What is Schistosoma hematobium?

Answer 12

• Seen in Middle East
• Young male
• Bug embeds in bladder wall → chronic inflammation ⇒ squamous metaplasia
  
  • results in squamous cell carcinoma

Question 13

What is adenocarcinoma?

Answer 13

Malignant proliferation of glands

Question 14

What does an Adenocarcinoma of the lower urinary tract arise from?

Answer 14

• Urachus remnant
  
  • do not normally have glandular tissue in bladder
  • embryological structure that helps fetus drain waste from bladder into the yolk sac
    
    • lined with glandular cells → most commonly at the dome of the bladder

Question 15

How is cystitis glandularis a risk factor for Adenocarcinoma?

Answer 15

• Chronic inflammation of the bladder
  
  • get columnar metaplasia from chronic inflammation
    
    • becomes adenocarcinoma

Question 16

What is bladder exstrophy? How is it associated with Adenocarcinoma of the lower urinary tract?

Answer 16

• Congenital failure to form caudal (lower) portion of bladder wall & abdominal wall
  
  • exposes surface of bladder to outside
  • increased risk for adenocarcinoma later in life