Ultrasound verification of bladder damage is associated with known biomarkers of bladder cancer in adults chronically infected with Schistosoma haematobium in Ghana

Abstract

Long-term infection with urinary schistosomiasis has been associated with development of bladder cancer. However, bladder cancer is difficult to diagnose without invasive measures such as cystoscopy, thus there is little information on the epidemiological extent of the problem. Studies have been either case-control studies or case examinations in different geographical areas, estimating a schistosome-associated bladder cancer incidence of 3-4 cases per 100,000. We have used three indicators to examine the potential bladder cancer problem in an adult rural population in Ghana endemic for urinary schistosomiasis: (i) parasitological positivity; (ii) age prevalence of bladder damage from ultrasound scans; and (iii) detection of biomarkers associated with the presence of bladder cancer. Biomarkers were BLCA-4 test (urine) and nuclear morphometry or quantitative nuclear grading (QNG) of epithelial cells (urine sediment), which quantifies DNA ploidy status and nuclear morphometric descriptors, both of which can detect the presence of bladder cancer. Our data show an increasing association between age, severe bladder abnormalities and the occurrence of these biomarkers. Sixty-two of 73 cytopathology Papanicolaou-stained smears were seen to have squamous metaplasia. Although further investigations are needed, we suggest that schistosome-associated bladder cancer is an important public health concern in areas where Schistosoma haematobium is prevalent.