Evaluating the Association of Multiple Environmental Cofactors Which May Contribute to Neoplastic Sequence of Schistosomal Associated Squamous Cell Carcinoma of the Bladder: A Systematic Scoping Review for Potential Public Health Intervention
Background: Schistosomiasis is the fourth most neglected tropical disease worldwide. Over 200 million people are infected and over 779 million people are at risk of infection. Out of the three major flatworms that infect humans, Schistosoma haematobium is the most prevalent and accounts for 2/3 of the infections worldwide. Chronic infection with S. haematobium leads to calcification of the bladder and lower ureters and potentially development of squamous cell carcinoma (SCC) of the bladder. Many external risk factors including exposure to smoking, vitamin A deficiency, HPV co-infection, and bacterial co-infection have been implicated in contributing to schistosomal associated bladder cancer. However, to date, no systematic review has assessed the quality of data of these assertions. Reviewing the evidence for the potential association between the listed risk factors and SCC onset can give insight into the possibility of implementing public health programs which reduce exposure to the added risk factors. ^ Method: Ovid Medline, PubMed, Embase, and Scopus databases were systematically searched and reviewed. A total of 16 articles met all inclusion criteria and were included in the qualitative analysis. ^ Results: Results showed that tobacco smoke could potentially affect schistosomal-SCC onset. However, OR were modest. The results also suggest that smoking may act in conjunction with genetic mutations and should be studied together to see if they have a synergistic effect on schistosomal-SCC onset. The results also show that elevated carotene levels may be associated with S. haematobium infection and may contribute to SCC onset. In addition, decreased levels of vitamin A were found in SCC patients and may also play a role in SCC-onset. The studies also showed a higher prevalence of HPV in S. haematobium related cancer and an increase in urinary tract infections in SCC patients. ^ Conclusions: There are too few studies to conclude an association between the listed external factors and schistosomal SCC. Likewise, studies were designed differently making comparisons difficulty. Future studies should ensure only S. haematobium infection and confirm SCC bladder cancer subtype^
Environmental health|Public health
Soeung, Victoria, "Evaluating the Association of Multiple Environmental Cofactors Which May Contribute to Neoplastic Sequence of Schistosomal Associated Squamous Cell Carcinoma of the Bladder: A Systematic Scoping Review for Potential Public Health Intervention" (2018). Texas Medical Center Dissertations (via ProQuest). AAI10792494.