Diagnosis and outcome of extranodal primary intestinal lymphoma in inflammatory bowel disease: an ECCO CONFER case series.

BACKGROUND There is a small but measurable increased risk of lymphoma in inflammatory bowel disease (IBD), with a suggestion that primary intestinal lymphoma in IBD is associated with inflamed tissue and immunosuppressant use, mainly thiopurines. METHODS This multicentre case series was supported by the European Crohn's and Colitis Organisation (ECCO) and performed as part of the Collaborative Network of Exceptionally Rare case reports (CONFER) project. Clinical data were recorded in a standardized case report form. RESULTS Fifteen patients with intestinal lymphoma from 8 centres were included [12 males, 11 patients with Crohn's disease, mean age 47.8 (±16.4 SD, range 26-76) years at lymphoma diagnosis]. Lymphoma type was diffuse large B-cell lymphoma (DLBCL) in 8, Hodgkin's disease in 2, MALT lymphoma in 3, and single cases of immunoblastic lymphoma and indolent T cell lymphoma. Lymphoma was located within the IBD affected area in 10 patients. At lymphoma diagnosis, 9 patients had a history of azathioprine or anti-TNF use. Lymphoma was diagnosed at a mean time of 10.4 (±7.07, 1-24) years after IBD diagnosis in 11 patients, prior to IBD in 2 and concurrently in 2. Sustained remission over a median follow-up time of 6.5 (1.5-20) years was achieved in 10 patients after treatment; 5 of them had started biologic therapy (including anti-TNFs, vedolizumab and ustekinumab) for active CD subsequent to their PIL treatment. CONCLUSION In this small case series, two thirds of patients developed lymphoma in the IBD-affected area, and almost two thirds had a history of thiopurine or anti-TNF use. Biologics were restarted without recurrence of lymphoma in half of the remitters.