Patients with inflammatory bowel disease (IBD) may be at an increased risk for developing lymphoma, a risk that has increased in patients with Crohn’s disease in recent years, according to a new study published by Olén et al in Clinical Gastroenterology and Hepatology. The new findings revealed that the risk increased in patients taking modern IBD medications and, less so, in patients not taking these medications, indicating the lymphoma risk may be affected by both IBD drugs and the disease activity itself.
“Previous studies of the lymphoma risk of [patients with] IBD have been too small to draw reliable conclusions,” explained lead study author Ola Olén, MD, PhD, Associate Professor of Clinical Epidemiology in the Department of Medicine Solna at the Karolinska Institutet and a senior consultant in the Department of Pediatric Gastroenterology and Nutrition at Sachs’ Children and Youth Hospital. “The studies have not taken into account…important systematic errors or been representative of today’s patients [with IBD],” he added.
Study Methods and Results
In the new study, researchers compared about 170,000 patients who had IBD with a matched population of those without IBD to calculate their risk of developing lymphoma. The researchers discovered that patients with both Crohn’s disease and ulcerative colitis had a higher risk of lymphoma. The risk was highest, however, in patients with Crohn’s disease—where the increase was driven mainly by T-cell lymphoma and aggressive B-cell lymphoma.
“We found an elevated relative risk of different types of lymphoma in both [patients with] Crohn’s disease and ulcerative colitis, but we need to point out that the absolute risk is very low,” highlighted senior study author Jonas F. Ludvigsson, MD, PhD, Professor of Medical Epidemiology and Biostatistics at the Karolinska Institutet; Adjunct Professor at Columbia University; and a senior physician in the Department of Pediatrics at the Örebro University Hospital. “The increase in risk equates to only 1 extra case of lymphoma in 1,000 [patients] with IBD, who were followed for 10 years,” he noted.
Although the highest risk of developing the cancer was observed in patients who had received immunomodulating agents, the researchers found that patients who were not on such medications were also at a higher risk of developing lymphoma.
Conclusions
“[These] findings indicate that both the inflammation in itself and its treatment play a part. Since there’s a lot of talk about the lymphoma risk associated with immunomodulating [agents], it’s important to make it clear that…the disease and the inflammation [intrinsically] seem to drive the development of lymphoma [as well]. One has to take account of this and discuss it when prescribing modern treatments where there might be a concern that they will increase the risk of lymphoma,” Dr. Olén underscored. “We now want to use more detailed data to answer the question about what’s most important in terms of the lymphoma risk—the disease itself or its treatment?” concluded Dr Olén.
Disclosure: For full disclosures of the study authors, visit cghjournal.org.
