A case of lymphoepithelioma-like carcinoma of the colon with ulcerative colitis

Abstract

Follow-up colonoscopy of a 25-year-old Japanese man with ulcerative colitis (UC) who had undergone endoscopic mucosal resection twice for early colon cancers revealed the presence of a new 1.5-cm-diameter tumor in the sigmoid colon. It was diagnosed by preoperative biopsy as a poorly differentiated adenocarcinoma. Sigmoidectomy was performed, and the pathological findings revealed lymphoepithelioma-like carcinoma (LEC). In situ hybridization to detect Epstein-Barr virus (EBV)-encoded small RNAs showed positive signals in stromal lymphocytes, but weak signals in the tumor cells. The association between EBV and LEC was obscure in this case. Unlike typical UC-mediated colon cancers, the lesion was poorly differentiated, and negative for p53 signals immunohistochemically. These findings may hint at a novel mechanism of carcinogenesis in UC-mediated colorectal cancer.

Small bowel Epstein–Barr virus‐positive lympho‐epithelioma‐like carcinoma in Crohn's disease

“…Of note, the tumour showed positivity for EBV, which is reported to be the most prevalent intestinal infection in non‐neoplastic mucosa of inflammatory bowel disease, especially in steroid‐refractory cases. Moreover, a case of EBV‐positive LEC was described in the rectum of a patient affected by ulcerative colitis . Our report suggests that the role of EBV in small bowel carcinoma development in the setting of inflammatory bowel disease deserves further investigation.…”

“…Moreover, a case of EBV-positive LEC was described in the rectum of a patient affected by ulcerative colitis. 1 Our report suggests that the role of EBV in small bowel carcinoma development in the setting of inflammatory bowel disease deserves further investigation.…”

Lymphoepithelioma-Like Carcinoma of the Colon

“…To our knowledge, only 7 cases, including the present (4 males, 3 females; are range 25–85 years, mean age 62.1 years), of LELC occurring in the colon have been reported (table 1) [3, 4, 5, 6, 7, 8]. The sites of involvement in these cases were widely distributed from the ascending colon to the rectum.…”

“…Other molecular pathways, such as EBV participation, resemble LELC carcinogenesis of other organs. EBV infection may be involved in carcinogenesis in cases with a background of ulcerative colitis by behaving as a stimulating factor for neoplasia in preneoplastic cells [7]. …”

Epstein-Barr Virus Infection Is Common in Inflamed Gastrointestinal Mucosa

“…[23] Cross-reactive humoral immune responses to EBV antigens are proposed as a mechanism of autoimmunity, as is infection-driven persistence of autoreactive B cells. [24–28] It is feasible that active viral replication could also contribute to pathogenesis of inflammatory processes.…”