Inflammation-Masked Sporadic Colorectal Cancer Detected After Remission Induction in Elderly-Onset Ulcerative Colitis
Tomotaka Tanaka, Yoshikazu Yoshifuku, Hajime Teshima, Hirona Konishi, Junichi Zaitsu, Kazuyoshi Nakata, Nodoka Otabe, Takeshi Mori, Michihiro Nonaka, Yoshifumi FujimotoABSTRACT
A 73-year-old patient with newly diagnosed ulcerative colitis (UC) presented with pancolitis and no detectable neoplastic lesion at initial colonoscopy. After remission induction with corticosteroids and maintenance therapy with azathioprine, follow-up colonoscopy 1 year later revealed a 10 mm 0-IIa + IIc lesion in the ascending colon. Endoscopic submucosal dissection demonstrated well-differentiated adenocarcinoma with submucosal invasion. No dysplasia was identified in the surrounding mucosa, and p53 overexpression was confined to the tumor, a finding more compatible with a sporadic phenotype than with colitis-associated neoplasia.
This case suggests that active inflammation may have masked a preexisting colorectal neoplastic lesion, highlighting the importance of colonoscopic reassessment after remission induction in elderly-onset UC.