Bladder Cancer

Basics

A primary cancer tumor originating in cells lining the urinary bladder lumen

Description

  • Bladder cancer (BC) cell types: urothelial carcinoma (formerly named transitional cell) and others (squamous cell and adenocarcinoma)
    • Urothelial carcinoma comprises >90% of all cases in the USA and Europe.
  • The spectrum BC relates to tumor penetration into muscularis propria layer or not:
    • Nonmuscle invasion (NMIBC)
    • Muscle invasion (MIBC)
    • Metastatic disease (MIBC plus spread beyond the bladder)
  • Very rarely, uroepithelial carcinoma or rhabdomyosarcoma of the bladder in children

Epidemiology

Primarily white men aged >55 years who smoke tobacco

Incidence

  • Estimated 4.2% of all new cancer cases in 2023
  • Increases with age (median age at diagnosis is 73 years)
  • Two times more common in Whites than in other races
    • Incidence rate in Asia is predicted to rise 74% from 2020 to 2024, compared to 52% in North America.
  • Male > female (3 to 4:1); but in smokers, risk is 1:1.
    • Fourth most common cancer in men and the eighth most common cause of cancer death in United States
    • Lifetime risk: 1 in 28 for men, 1 in 91 for women
    • Women are diagnosed in more advanced stages than men (hematuria mimicking gynecologic illnesses).
  • Decreased incidence rate primarily in men in 2004–2020
  • 15.8/100,000 new cases age-adjusted rate for all in 2020, the United States

Prevalence

  • Lifetime risk is 2.3% overall based on 2017–2020 data in United States.
  • In 2020, 725,549 cases in the United States, far exceeding the population of Wyoming or Vermont.

Etiology and Pathophysiology

Unknown, other than related to risk factors

  • 70% is nonmuscle invasive, longer survival.
  • 30% of tumors are muscle invasive at presentation, prognosis worse.

Genetics

  • Same-sex, monozygotic twins have 10% increase risk.
  • Patient with Lynch syndrome has up to 20% lifetime risk due to altered DNA mismatch repair genes.

Risk Factors

  • Male sex
  • Advanced age, greatest single risk factor, due to prolonged exposure time to risky substances
  • Tobacco smoking is the single greatest modifiable risk factor.
  • 50% cases attributed to personal smoking.
  • Secondhand tobacco smoke exposure or e-cigarettes contain carcinogenic compounds.
  • Other risk factors:
    • Occupational exposures to benzidine; magenta, auramine dyes; aluminum and rubber production; certain paints, plastics, carbon black dust (printing ink), petroleum, and diesel exhaust; and soot from chimneys
    • Arsenic exposure in drinking water
    • History of bladder radiation, pelvic irradiation, or certain chemotherapy drugs like cyclophosphamide or ifosfamide
    • Chronic lower UTI or chronic indwelling urinary catheter
    • Pioglitazone (diabetes), aristolochic acid (herbal supplement), cyclophosphamide, and chlornaphazine
ALERT
Microscopic (≥3 RBC/hpf) or gross hematuria found in a smoker needs cystoscopy and axial upper tract imaging, regardless of anticoagulation or antiplatelet status, unless there is a documented UTI with urgency and frequency that responds to UTI treatment or if related to a gynecologic or other non-malignant genitourinary cause.

General Prevention

  • Avoid tobacco smoke exposure.
  • https://www.cdc.gov/tobacco/quit_smoking/index.htm or 800-QUIT NOW (800-784-7669)
  • Counseling of avoidance in individuals with risky occupational exposure
  • Prompt follow-up for individuals with hematuria, regardless of anticoagulation or antiplatelet status

There's more to see -- the rest of this topic is available only to subscribers.