Chronic inflammatory bowel diseases (IBD) are associated with an increased risk of gastrointestinal cancers, influenced by various individual factors and the duration of disease progression. The aim of this study was to assess neoplastic transformation in patients with IBD based on the experience of our center.

We conducted a retrospective single-center study spanning 2017 to 2024. Data were collected from patient medical records

We report a series of 11 patients who developed tumors in the context of IBD: 10 with Crohn’s disease and 1 with ulcerative colitis (sex ratio 1.2). Neoplasia was the presenting feature in five cases. In the remaining cases, the mean duration of IBD prior to diagnosis was 9.16 years (range 1–16). Five patients had been treated with corticosteroids. Only one was on salicylates, while the others had not received any maintenance therapy. The tumors were diagnosed under various circumstances: screening colonoscopy (1 patient), symptomatic presentation (e.g., weight loss, bowel habit disturbances) in 6 patients, or tumor-related complications such as superinfection or acute intestinal obstruction (4 patients). The mean age at tumor diagnosis was 60 years (range 36–88). Among the identified tumors, two patients had MALT lymphoma—one located in the colon and the other in the cecum. One of these cases showed isolated colonic involvement, while the other revealed additional lesions in the tonsils, nasopharynx, duodenum, and ileum. Treatment involved a combination of surgical resection and chemotherapy (Chlorambucil-Rituximab). Nine patients were diagnosed with infiltrating adenocarcinoma: 4 in the small intestine, 1 in the cecum, 1 in the colon, and 3 in the rectum. One case presented with metastases. Additionally, one patient with rectal adenocarcinoma was found to have a neuroendocrine tumor (NET) in the colon, diagnosed through stepwise colonic biopsies. All patients underwent surgical resection and chemotherapy: 5 ileocolic resections, 1 subtotal colectomy, 1 anterior resection, and 2 abdominoperineal amputations with total proctocolectomy and permanent ileostomy. Two patients also received radiotherapy. After a mean follow-up of 205 months (range 2–1496), 4 patients were in remission without recurrence—one of whom developed nodular regenerative hyperplasia as a chemotherapy complication. Two patients were still receiving adjuvant treatment, and 5 were lost to follow-up.

Neoplasms linked to chronic inflammation in IBD are not uncommon and may be the initial presentation, as seen in nearly half of our cases—highlighting frequent underdiagnosis. This series also includes two rare cases of colonic MALT lymphoma, an association rarely reported. In patients with chronic ileal involvement, treatment strategies should consider early surgical options before initiating immunosuppressants. Additionally, the detection of a neuroendocrine tumor in a non-affected segment underlines the importance of systematic stepwise biopsies. These findings call for heightened clinical vigilance and further investigation into emerging and underrecognized tumor types in IBD.