Mammograms are all over the news. And now there's a report that maybe we don't need quite so many pap smears. But how much have you heard about screening for kidney and bladder cancer? Together, these cancers kill about 24,000 Americans per year, a rate comparable to breast cancer, which kills about 40,000 American women per year.
These numbers are from the Centers for Disease Control and Prevention, quoted in Reference 2. The authors explain that there are no recommendations to screen the general population for kidney or bladder cancer, because such a screening program would not be cost effective.
Blood in the urine is the primary screening test for urological cancers in women. Urinary tract infections and kidney stones can also produce blood in the urine, and protein in the urine (indicating chronic kidney disease) can produce a false positive test with the dipstick method. For kidney cancer, ultrasound and computed tomography imaging are more specific tests which are much more expensive.
Screening for bladder cancer is recommended for patients with recognized risk factors:
1. Tobacco use
2. Occupational exposure to carcinogenic chemicals
3. Exposure to phenacetin, cyclophosphamide, or pelvic radiation therapy
4. Chronic urinary tract infection
5. Spinal cord injury with intermittent catheterization or indwelling catheter.
Screening for kidney cancer is recommended for patients with a family history of renal cell carcinoma, and for selected patients with end-stage renal disease.
The new mammograms recommendations are similar: screening should be limited to patients with risk above some level considered significant. Reference 2 reports an estimate that mammograms cost $232,000 per “quality-adjusted life-year gained from screening test”. For comparison, the prostate specific antigen test costs $8,700 to $145,000 for the same health benefit, and is recommended for men starting at age 50, and for those at elevated risk starting at age 40.
If we had infinite money available for health care, we might want to screen everyone for every possible cancer.