Clinical and epidemiological features of patients with genitourinary tract tumour in a blackfoot disease endemic area of Taiwan.

OBJECTIVES

To evaluate the clinical and epidemiological characteristics of patients with genitourinary (GU) tract transitional cell carcinoma (TCC) in an endemic area of blackfoot disease (BFD), the arsenic-exposed group, to compare them with characteristics among other non-BFD endemic areas (unexposed group).

PATIENTS AND METHODS

In all, 474 patients with pathologically diagnosed GU-TCC were enrolled in the study. All follow-up data were prospectively collected and entered into a database throughout the study period. Statistical analysis was used to determine the association between clinical variables and prognosis, and multivariate regression models were used to assess the association between arseniasis and mortality from GU-TCC.

RESULTS

There were no significant differences between the groups in age, sex, tumour stage and grade. However, the exposed group had a significantly higher proportion of females. The overall 5-year survival rate of patients with upper urinary tract (UUT) TCC was 49%, and the two groups had similar 5-year survival rates. The overall 5-year survival rate of patients with urinary bladder (UB) TCC was 68.3%, and there was a statistically significant difference in survival between the groups, with a 5-year survival rate of 58.7% for the exposed and 72.4% for the unexposed group. For patients with early-stage (pTa and pT1) UB cancers, the death rate was five times higher in exposed patients with tumour progression and recurrence after transurethral resection of bladder tumour than in the unexposed group.

CONCLUSIONS

There was a significantly higher mortality rate for UB-TCC among exposed patients in the area endemic for arseniasis than in those from other non-endemic areas. The arsenic content of artesian-well water might contribute to the increased ratio of female patients with GU-TCC and the unusually high incidence of UUT-TCC in the BFD endemic area in Taiwan.