Wallach's Interpretation of Diagnostic Tests: Pathways to Arriving at a Clinical Diagnosis (231 page)

   Suspected patients are older than age 40 years, more commonly males with a history of cigarette smoking, who present with hematuria (painless, intermittent, grossly visible, and present throughout micturition), or irritative voiding symptoms (frequency, urgency, dysuria) that suggest carcinoma in situ (CIS) of the bladder.

   The association of pain with bladder cancer (located to the flank; suprapubic, hypogastric, and perineal; abdominal or right upper quadrant areas; bone pain; or headache/disordered cognitive function) can be signs of locally advanced or metastatic disease. Constitutional symptoms (fatigue, weight loss, anorexia, failure to thrive) are usually signs of advanced or metastatic disease and carry a poor prognosis.

   The definitive diagnosis and staging of bladder cancer are by cystoscopy, beginning with a baseline evaluation of the bladder and uninvolved mucosa to record the number, size, location, appearance, and growth type (papillary or solid) of all lesions observed. Visible lesions can be biopsied or resected for histologic analysis.

   Laboratory Findings

   Urinalysis: A positive dipstick test (detecting one to two red cells per highpower field [HPF]) should be confirmed by microscopic analysis (below). Infection should be ruled out by a urine culture prior to further workup of hematuria.

   Urine sediment: Hematuria is significant if there are greater than three red cells per HPF, present throughout micturition. The presence of dysmorphic red cells or casts suggests a glomerular origin, whereas normally formed red cells likely originate from infections, tumors, or obstructions/calculi. The specimen should be maintained at room temperature and examined within 30 minutes of collection.

   Urine cytology: Urine cytologic analysis by fluorescence in situ hybridization (e.g., UroVysion™ FISH) can be a useful noninvasive aid both in the primary diagnosis of urothelial carcinoma and in monitoring tumor recurrence (occurring in about 70% of cases after initial treatments). UroVysion™ FISH is designed to detect certain numerical chromosomal abnormalities commonly associated with urothelial carcinoma (either amplifications of chromosomes 3, 7, and 17 or deletions of the 9p21 locus).

   Urine biomarkers: Several urine-based biomarkers have been approved for diagnosis or surveillance of patients with a history of the disease. However, their sensitivity is low, and their use is not recommended for an initial workup of a suspected case.

   Limitations on Interpretation of the UroVysion™ FISH Test for Bladder Cancer

   A positive result in the absence of clinical evidence of urothelial bladder cancer may indicate urothelial malignancies of other organs along the GU tract (kidney, ureter, prostate, or urethra).

   A negative result in the presence of other signs or symptoms of urothelial carcinoma may suggest a false-negative test.

Suggested Readings

Getzenberg RH. Urine-based assays for bladder cancer.
Lab Med.
2003;34:613–617.