Immunotherapy to treat cancer gave rise to 2nd cancer in extremely rare case

In an extremely rare case, a patient who received a cell-based cancer treatment later developed a second cancer that arose from the treatment itself. 

Known as chimeric antigen receptor (CAR) T-cell therapy, the treatment involves harvesting a patient's immune cells and genetically modifying them to target and attack specific types of cancers, including lymphomas, leukemias and multiple myeloma. For many people, the treatment has been life-changing — however, as the first CAR T-cell therapy was only approved in 2017, scientists are still learning about the treatment's benefits and risks.

Secondary cancers are known to occur in 4% to 16% of people following chemotherapy and radiation therapy, but so far, only about 20 cases of T-cell cancer after CAR T therapy have been reported to the Food and Drug Administration (FDA) Adverse Events Reporting System database. Given that more than 34,000 people in the U.S. have received the treatment, CAR-related secondary cancers appear quite rare. 

Despite the low risk, these sporadic cases have drawn scrutiny from the FDA and left the research community with unanswered questions about the underlying causes and potential risk of CAR-related secondary cancers. The FDA maintains that the overall benefit of these therapies outweighs potential risks, but the agency wants to better understand the risks, nonetheless.

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Now, a new case study, published Tuesday (June 12) in The New England Journal of Medicine, provides important insight into secondary cancers that may arise following CAR T-cell therapy.

The report details the case of a 71-year-old woman with a History of multiple myeloma, a type of cancer that affects immune cells in the blood. The patient developed severe gastrointestinal symptoms four months after receiving CAR T-cell therapy. Upon further investigation, her doctors found that she had developed a new cancer in her intestinal tract.