Arsenic exposure predicts bladder cancer survival in a US population.
OBJECTIVE
Chronic arsenic exposure at levels found in US drinking water has been associated with bladder cancer. While arsenic is a known carcinogen, recent studies suggest that it is useful as a therapeutic agent for leukemia. This study examined the relationship between arsenic exposure and bladder cancer mortality.


METHODS
We studied 832 cases of bladder cancer diagnosed in New Hampshire from a population-based case-control study. Individual exposure to arsenic was determined in home drinking water using ICP-MS and in toenail samples by instrumental neutron activation analysis.


RESULTS
Among the high arsenic exposure group, found using toenail arsenic level or arsenic consumption, cases experienced a de-escalated survival hazard ratio (HR) [high (> or =75 percent) versus low (<25th percentile) toenail arsenic overall survival HR 0.5 (95% CI 0.4-0.8)], controlled for tumor stage, grade, gender, age and treatment regimen. This association was found largely among invasive tumors, in smokers and was not modified by TP53 status. Bladder cancer cause-specific survival showed a similar trend, but did not reach statistical significance [HR 0.5 (95% CI 0.3-1.1)].


CONCLUSIONS
Arsenic exposure may be related to the survival of patients with bladder cancer.
Kwong
Ryan C
RC
Section of Biostatistics and Epidemiology, Department of Community and Family Medicine, Norris Cotton Cancer Center, Dartmouth Medical School, 7927 Rubin 860 One Medical Center Drive, Lebanon, NH 03756, USA.
Karagas
Margaret R
MR
Kelsey
Karl T
KT
Mason
Rebecca A
RA
Tanyos
Sam A
SA
Schned
Alan R
AR
Marsit
Carmen J
CJ
Andrew
Angeline S
AS
D000328:Adult; D000368:Aged; D001151:Arsenic / Q000032:analysis*; D016022:Case-Control Studies; D004781:Environmental Exposure / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009262:Nails / Q000737:chemistry; D009513:New Hampshire / Q000453:epidemiology; D011237:Predictive Value of Tests; D012307:Risk Factors; D040242:Risk Reduction Behavior; D012907:Smoking / Q000401:mortality; D016019:Survival Analysis; D014481:United States / Q000453:epidemiology; D001749:Urinary Bladder Neoplasms / Q000401:mortality*; D014881:Water Supply / Q000706:statistics & numerical data*
D001151:Arsenic