Sigmoid cancer associated with Schistosoma japonicum in a non-endemic area case report and literature review

Introduction: Colorectal cancer (CRC) is the third most common malignant tumor globally, but the exact pathogenic causes and related mechanisms still require further research. Schistosoma japonicum has been classified by the International Agency for Research on Cancer (IARC) as a probable carcinogen in humans (class 2B) causing liver cancer. Nonetheless, the experimental evidence supporting the association of S. japonicum infection with colorectal carcinogenesis is meager Case: A 61-year-old woman from the Philippines who migrated to the UAE 11 years ago, presented with a history of rectal bleeding and underwent a colonoscopy revealing a huge sigmoidal circumferential polypoid lesion obstructing the lumen, Histopathological examination of the obtained biopsies revealed moderately differentiated adenocarcinoma and a background of eosinophilic colitis due to S. japonicum ova deposition (viable and calcified). Clinical discussion: Schistosoma, one of the most clinically relevant genera of parasites, is a significant cause of morbidity and mortality in humans. The exact pathophysiology of CRC in the setting of S. japonicum infection is not fully understood. It is believed that inflammation plays a key role in the development of CRC. An important consideration is if there is a difference between the outcome of schistosomal colorectal cancer (CRC-S) and non-schistosomal colorectal cancer (CRC-NS). Conclusion: S. japonicum is one of many pathogens that carries both gastrointestinal manifestations and carcinogenic properties. Although it is endemic in specific regions of the world, it is imperative to keep it in mind especially if the patient has a history of travel to any of those endemic regions.