Norm of Bladder tumor–associated antigen (BTA) Test for Bladder Cancer
Bladder tumor–associated antigen negative.
Usage of Bladder tumor–associated antigen (BTA) Test for Bladder Cancer
Used in the diagnosis of superficial transitional cell carcinoma of the urinary bladder. Has a 61% sensitivity, 74% specificity, 64% accuracy, 88% positive predictive value, and 38% negative predictive value for bladder carcinoma (Lokeshwar et al, 2002).
Positive of Bladder tumor–associated antigen (BTA) Test for Bladder Cancer
Presence of bladder tumor–associated antigen in urine sample.
Negative of Bladder tumor–associated antigen (BTA) Test for Bladder Cancer
Absence of bladder tumor–associated antigen in urine sample.
Description of Bladder tumor–associated antigen (BTA) Test for Bladder Cancer
Bladder tumor–associated antigen (BTA) test is a noninvasive tumor-marker quantitative enzyme immunoassay. The tumor marker is an antigen named “human complement factor H–related protein” (hCFHrp). hCFHrp is not detectable in healthy epithelial cells but has been identified in bladder cancer cells. hCFHrp is similar to human complement factor (hCFH), which plays a role in the prevention of cell lysis through interruption of a complement pathway. hCFH causes lysis of foreign cells in a host by inhibiting the development of a membrane attack complex. Cancer cells are believed to be protected from lysis by hCFHrp, which also interrupts a complement pathway, thereby facilitating invasion to the host.
Professional Considerations of Bladder tumor–associated antigen (BTA) Test for Bladder Cancer
Consent form NOT required.
- Urine specimen suggested amount is 35 mL (minimum of 2 mL).
- Collect voided or catheterized urine sample in clean urine specimen container without additives. Urine specimens cannot be collected in foam or paper cups.
- Transport to lab on ice.
Client and Family Teaching
- Obtain complete medical history (including current medical state).
- Use a dipstick urine to verify absence of hematuria before test.
- Inform client that a positive bladder tumor antigen test will be confirmed by biopsy of bladder tissue.
Factors That Affect Results
- False-positive tests occur in 9% of cases (Friedrich et al, 2002) including any condition that causes hCFHrp to be present in the bladder. These conditions are renal lithiasis, nephritis, renal neoplasm, urinary tract infections, cystitis, history or presence of urinary stents or nephrostomy tubes, genitourinary cancer, bowel interposition segment, and trauma to the urinary system. A false-negative test occurs in 2% of those tested and is associated with tumor recurrence.
- Hematuria may yield false-positive tests, and therefore urine samples should first be tested for the presence of blood.
- If blood is detected in urine sample, urine cytologic testing is suggested.