The objective of our study was to verify a suspected increased incidence of nontransitional cell carcinoma (TCC) of the bladder in female patients treated at our institution. The study included 169 patients, 83% of whom resided in the Texas Gulf Coast region. Tumors were considered TCC or non- TCC on the basis of their predominant histologic pattern. The incidence of non-TCC among men (8.1%) was comparable with data from American tumor registries and European studies. In contrast, our female patients exhibited a marked increased incidence of non-TCC (42.3%), which is approximately five times higher than that in other series. All male and female patients with non-TCC had invasive disease. History of urinary tract infectious was strongly associated with non-TCC. Our results suggest that our sample of the female population in the Texas Gulf Coast region has a significantly high incidence of non-TCC. This unusual trend merits further investigation.