Colorectal cancer in a patient with intestinal schistosomiasis: a case report from Kilimanjaro Christian Medical Center Northern Zone Tanzania

BACKGROUND: Colorectal cancer associated with chronic intestinal schistosomiasis has been linked with the chronic inflammation as a result of schistosomal ova deposition in the submucosal layer of the intestine. Among all species Schistosoma japonicum has been more linked to development of colorectal cancer as compared to Schistosoma mansoni due to absence of population-based studies to support the association. Despite the weak evidence, some cases have been reported associating S. mansoni with development of colorectal cancer. CASE PRESENTATION: We report a patient who presented to us as a case of intestinal obstruction and found to have a constrictive lesion at the sigmoid colon at laparotomy, then later found to have colorectal cancer with deposited S. mansoni ova at histology. CONCLUSION: Given the known late complications of schistosomiasis, and as S. mansoni is endemic in some parts of Tanzania, epidemiological studies are recommended to shed more light on its association with colorectal cancer.