- Clinical science
Carcinoma of the epithelial lining of the urinary tract is known as urothelial cancer and may involve the bladder (most common), renal pelvis, ureters, and urethra (rare). Most urothelial cancers occur in males > 65 years, esp. those who have a history of smoking or exposure to carcinogens. Patients often present with painless gross hematuria or irritative voiding symptoms, although some cases are incidentally detected (microscopic hematuria on urinalysis). Urine cytology, cystoscopy, and CT urography are indicated in all patients with gross hematuria or in patients > 35 years of age with microhematuria and risk factors for urothelial cancer. Non-muscle, invasive bladder tumors are treated with transurethral resection of the tumor and intravesical instillation of BCG or chemotherapeutic agents. Muscle invasive bladder tumors are treated with radical cystectomy and chemotherapy or chemoradiation. Since cancers of the renal pelvis are often multifocal and have a high risk of recurrence, treatment requires nephroureterectomy. Metastatic urothelial cancer is treated with palliative chemotherapy and/or chemoradiation. Close follow-up post-treatment is necessary to identify and treat recurrent disease.
- Urothelial cancer; is the most common tumor of the urinary tract.
- Sex: ♂ > ♀ (3:1)
- Race: white populations > black populations (2:1)
- Peak incidence: 65 years
- Cancer sites:
- Histological types
Epidemiological data refers to the US, unless otherwise specified.
- Tobacco use
- Prolonged (occupational) exposure to carcinogens (e.g., aromatic amines like benzidine and aniline dye; azo dye, heavy metals)
- Chronic inflammation; of the urinary tract (e.g., chronic/recurrent UTI, schistosomiasis)
- HPV 16 infection
- Increased chlorine/arsenic content in drinking water
- Iatrogenic: pelvic irradiation; cyclophosphamide treatment; bladder augmentation surgery (e.g., with ileum/colon)
- Previous or family history (genetic predisposition) of urothelial cancer
|Location||Symptoms||Features of advanced/metastatic disease|
|Bladder carcinoma|| |
- Urinalysis: indicated in all patients with hematuria
- Gross hematuria
- Symptomatic microscopic hematuria
- Asymptomatic microscopic hematuria with a negative initial workup and continued suspicion for urothelial carcinoma
- Findings: malignant cells
- Complete blood count: anemia or thrombocytopenia may be present
- Renal function tests: ↑ BUN and ↑ creatinine may be present
- Coagulation profile: indicated if coagulopathy is suspected or if the patient is on anticoagulants/antiplatelet agents
Imaging and biopsy
CT urography and cystoscopy are indicated in all patients with gross hematuria and in patients > 35 years with asymptomatic microhematuria; . Physicians may consider cystoscopy and/or CT urography in patients < 35 years with asymptomatic hematuria who also have risk factors for CIS. These procedures enable diagnostic evaluation of the entire urinary tract, as well as follow-up.
- CT urography: Imaging modality of choice to examine the entire urinary tract.
- Cystoscopy and biopsy: direct visualization of urethral and bladder mucosa with possible simultaneous biopsies or therapeutic resections
- Ultrasound (kidney, ureter, bladder): if CT is contraindicated (e.g., pregnant women)
- Retrograde urethrogram: detects location and extent of invasion of urethral tumors
- Flexible ureteroscopy: evaluation of ureteral lesions
Since urothelial tumors can be multifocal, the entire urinary tract must be evaluated!
- Chest x-ray: detects lesions and pleural effusions
- Liver function tests
- CT abdomen and pelvis : solid organ and lymphatic metastases
- Alkaline phosphatase measurement , bone scan
Treatment of urothelial cancers involves surgical resection with neoadjuvant chemotherapy and/or radiation. All cases of metastatic disease are managed with palliative systemic chemotherapy and palliative surgery, if needed (e.g., removal of urethral obstructions).
Nonmuscle invasive tumors (N0 M0)
- Low-risk tumor
- High-risk tumor : TURBT with adjuvant intravesical BCG or chemotherapy instillation
- Muscle invasive tumors with/without positive lymph nodes and M0
- Metastatic disease: palliative systemic chemotherapy
- Nonmetastatic disease: nephroureterectomy with excision of bladder mucosa adjacent to the ureteric orifice; indicated in all patients
- High-grade, lymph node positive patients: additional regional lymphadenectomy and adjuvant chemotherapy (e.g., gemcitabine and cisplatin for 4 cycles)
- Less extensive procedures
- Non-invasive tumors: transurethral resection of tumor with intraurethral instillation of chemotherapy/BCG
- Invasive tumors: resection, followed by chemotherapy or chemoradiotherapy
- Follow-up procedures depend on the grade and stage of the tumor.
- In general, follow-up includes: