Abstract
A 68-year-old male with rectal cancer and a history of Schistosomiasis japonicum (S-J) infestation underwent low anterior resection. In the resected specimen, many heavily calcified eggs of SJ were seen, distributed mainly in the submucosa adjacent to the tumor. Schistosomiasis due to S-J is a possible contributor to the development of colorectal cancer. In this case, the patient was infected by S-J at the Chikugo rever before age 20, over 40 years between the patient's acquisition of S-J and presentation with cancer may reflect unrelated spontaneous carcinogenesis, but the fact that eggs were heavily and extensively present in the resected specimen argues for a relationship between these eggs and the cancer. Coordinating treatment for schictozomiasis with systemic follow-up to detect cancer probably would be required to establish S-J eggs as a cancer promoter, the infestation of which presumably contributes to the cellular changes leading to premalignant tranformation of intestinal epithelial cells.
