EUF Vol. 1 No. 1

50 96

Point of Focus Debate: For
We Should Screen Smokers for Bladder and Kidney Cancer
Yair Lotan
Department of Urology, University of Texas Southwestern Medical Center, Dallas, TX, USA
No recommendations currently exist for the screening for
either kidney or bladder cancer, and these diseases are
diagnosed when patients become symptomatic or after
imaging for other causes. This commentary defends the
rationale for screening smokers for bladder and kidney
cancer. Some important questions on the use of screening in
these malignancies need to be answered.
1. Who should be screened?
The several known risk factors for bladder and kidney
cancer include smoking, age, and gender Smoking
increases the risk for kidney cancer by 2-fold and >4-fold
for bladder cancer To justify screening, there needs
to be a sufficient prevalence of disease in a population;
otherwise, the cost of testing becomes exorbitant. This is
the rationale for using age to determine the timing of
screening for breast, colon, and prostate cancers. The same
approach can also be applied to bladder cancer. Data
extracted from the Prostate, Lung, Colorectal, and Ovarian
Cancer Screening Trial and the National Lung Screening
Trial showed that bladder cancer was identified in 1430
of 154 898 and 439 of 53 173 patients, respectively
. Although such numbers may argue against the use of
screening, in men aged >70 yr with a smoking exposure
30 pack-years (PYs), incidence rates were >5 per
1000 person-years, similar to the incidence of colon cancer
detection on sigmoidoscopy . Men aged >60 yr with a
smoking history >30 PYs had incidence rates >2 per
1000 person-years. Therefore, the use of age and smoking
history as selection criteria has the potential to identify
populations of sufficient risk to justify a screening strategy
for bladder and kidney cancer.
2. Which test?
Issues related to testing involve cost, invasiveness, com-
plications, and, most important, accuracy. False-positive
rates are critical to screening. If one were to test 30 million
smokers with a test with 99% specificity, 300 000 subjects
would have a positive test, which is four times as many
subjects as the number of bladder and kidney cancers
diagnosed. Nonetheless, testing can be used to detect both
bladder and kidney cancer.
The most accurate test currently available for bladder
cancer is cystoscopy that can be done in the office setting
with a minimal risk of bleeding and infection and relatively
low cost (<$300), but it is invasive. Noninvasive testing
with either hematuria dipstick testing or urine-based tumor
markers has been utilized . These tests tend to have a
higher sensitivity for high-grade tumors ranging from 60%
to 80%, but specificity is lower (50–75%). Because the
prevalence of microscopic blood in the urine can be as high
as 10–14%, a considerable number of subjects would require
cystoscopy, but this would still keep most patients from
undergoing invasive testing.
There are less data on potential testing for kidney cancer.
Cross-sectional imaging with computed tomography (CT)
or magnetic resonance imaging (MRI) is the most sensitive
way to detect renal masses, but CT and MRI are costly, and
CT has the added disadvantage of radiation. Renal ultra-
sound (US) is a noninvasive low-cost option that can be
performed in an office setting. One earlier review of US
found that the sensitivity and specificity for diagnosing
kidney cancer were 91% and 99%, respectively . In a more
recent study of 9959 volunteers, US had an 82% sensitivity
with a 99% specificity for kidney cancer Subjects with
available at
journal homepage:
* Corresponding author. Department of Urology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., J1.112, Dallas, TX 75390,
USA. Tel. +1 214 648 0389; Fax: +1 214 648 8786.
E-mail address:
2405-4569/# 2015 European Association of Urology. Published by Elsevier B.V. All rights reserved.