Bladder cancer ranks as the fourth leading cause of cancer-related death in men and tenth leading cause in women in the United States (Parkin et al., 2002). A delay in the diagnosis and treatment of bladder cancer results in a poorer outcome (Sanchez-Ortiz et al., 2003). An interval of longer than 3 months from the time of diagnosis of muscle invasion to cystectomy correlates with a higher pathological stage and decreased survival (Chang et al., 2003; May et al., 2004). Early recognition of symptoms of bladder cancer by primary care physicians with prompt referral and evaluation and treatment by a urologist is necessary for a successful result.
Early symptom recognition is the key to a better prognosis. The most common symptom of bladder cancer is painless haematuria, which occurs in 85% of patients. Nearly all patients with bladder cancer have at least microhaematuria if sufficient urine samples are tested (Messing and Vaillancourt, 1990). The degree of haematuria does not correlate with the extent of disease. Haematuria may be measured by indirect examination of the urinary sediment by the dipstick method, by direct examination of the centrifuged sediment (sediment count) or by determination of the number of red blood cells per millilitre of urine excreted (chamber count).
The most common method of screening patients for haematuria is haemoglobin dipstick. A sample is recorded as positive when any haemoglobin is present. The haemoglobin dipstick method is easy to use, inexpensive and does not require the presence of intact red blood cells. Dipstick testing for haematuria has a limited specificity (between 65% and 99%); therefore, an initial positive result by this method should be confirmed by microscopic evaluation of the urinary sediment (Messing et al., 1987; Woolhandler et al., 1989; Sutton, 1990). Because haematuria is intermittent in nature, repeat testing increases the sensitivity of the haemoglobin dipstick test.
Microscopic haematuria has been defined as three or more red blood cells per high power field on microscopic evaluation of urinary sediment from two of three properly collected urinalysis specimens (Grossfield et al., 2001). Patients with risk factors for significant disease (Table 6.1) should undergo a thorough evaluation for any degree of haematuria. The prevalence of asymptomatic microscopic haematuria in the general population ranges from 0.19% to 21% (Golin and Howard, 1980; Mohr et al., 1986; Sultana et al., 1996; Khadra et al., 2000). Mohr et al. (1986) reported that asymptomatic microhaematuria occurred in 13% of the general population and only 0.4% had urothelial neoplasia. The incidence of malignancy in patients over 50 years is higher, however. Sultana et al. (1996) found that 5% of patients older than 50 years with asymptomatic haematuria had an underlying malignancy. The incidence increased to 10% if there were associated symptoms.
Table 6.1Risk factors for significant disease in patients with microscopic haematuria