Lower Urinary Tract Carcinoma

Question 1

What is the most common type of lower urinary tract cancer? Where does it usually arise in? What is a major risk factor? Who is it seen in and how does it present?

Answer 1

Urothelial (transitional cell) carcinoma which is a malignant tumor arising from the urothelial lining of the renal pelvis, ureter, bladder or urethra. Usually arises in the bladder. Cigarette smoke. Additional risk factors are naphthylamine, azo dyes and long term cyclophosphamide or phenacetin use. Generally seen in older adults. Clasically presents with painless hematuria.

Question 2

What are the two pathways from which Urothelial (transitional cell) carcinoma arises?What mutations are they associated with? How do they progress?

Answer 2

1. Flat - develops as a high grade flat tumor and then invades. Associated with early p53 mutations.
2. Papillary - develops as a low grade papillary tumor that progresses to a high grade papillary tumor adn then invades. Not associated with early p53 mutations.

Question 3

What is squamous cell carcinoma ? Which urinary tract structure does it involve? What does it arise in? What are three risk factors?

Answer 3

Malignant proliferation of squamous cells, usually involving the bladder. Arises in a background of squamous metaplasia. Risk factors include chronic cystitis (older woman), Schistosoma hematobium infection (Middle Eastern/Egyptian male) and long-standing nephrolithiasis.

Question 4

What is adenocarcinoma ? Which urinary tract structure does it involve? Where does it develop? What does it arise in?

Answer 4

Malignant proliferation of glands usually involving the bladder. Arises from a urachal remnant (tumor develops at the dome of the bladder), cystitis glandularis or exstrophy (congenital failure to form the caudal portion of the anterior abdominal and bladder walls).