Arsenic Exposure and Temporal Trend of Incidence in Upper Urinary Tract Urothelial Carcinoma, 1979-2010: A Nationwide Population-based Study in Taiwan
1Yi-Sheng Tai, Chao-Yuan Huang, Huai-Chin Tai, So-Mong Wang, Yeong-Shiau Pu and Chung-Hsin Chen.
1Department of Urology, National Taiwan University Hospital, Yun-Lin Branch
Department of Urology, National Taiwan University Hospital
To investigate the newly diagnosed incidence of arsenic (AS)-related upper urinary tract urothelial carcinoma (UTUC) in Taiwan
Materials and Methods:
From 1979 through 2010, patients with UTUC were extracted from Taiwan Cancer Registry Database. According to birth residency, the patients were further divided into 4 areas, including the zone 0 (Z0) (a well water AS level of less than 350 ng/ml and no blackfoot disease), zone 1 (Z1) (a well water AS level of 350 ng/ml or greater and no blackfoot disease), zone 2 (Z2) (a well water arsenic level of less than 350 ng/ml with sporadic blackfoot or AS-related skin diseases ) and the zone 3 (Z3) (a well water AS level of 350 or greater and the blackfoot disease endemic area). The temporal trends for newly diagnosed rate were analyzed by linear regression. The incidences between groups were compared using Friedman's ANOVA. A p value of < 0.05 was considered statistically significant.
A total of 19,226 patients with newly diagnosed UTUC were identified, including 10,404 (54.1%) women and 8822 (45.9%) men. In 2010, the overall newly diagnosed rates of UTUC stratified by sex were 4.53%, 6.55%, 9.23% and 8.57% (female) as well as 4.35%, 4.95%, 5.75% and 9.28% (male) in Z0, Z1, Z2 and Z3, respectively. The trends of annual newly diagnosed incidences in the 4 areas increase from 1979 to 2010. People in Z3 area have significantly annual raising rate of incidence than those in Z0, Z1 and Z2 (female: 0.31% vs. 0.17%, 0.23% and 0.24%, p< 0.001; male: 0.25% vs 0.13%, 0.17% and 0.14%).
The overall incidence of UTUC in Taiwan is increasing from 1979 to 2010. People who lived in the high arsenic endemic area (Z3) had higher incidence of UTUC than people lived in other areas of Taiwan.