Immunotherapy May Increase Prevalence of Autoimmune Rheumatic Conditions

It has been long thought that there is a link between cancer and autoimmune rheumatic diseases. Clinicians are increasingly observing an association between immunotherapy drugs for cancer and an increase in rheumatologic immune-related side effects, according to a session presented at the American College of Rheumatology/Association of Rheumatology Health Professionals

Annual Meeting.

“Recent data suggest that both cancer and cancer therapy could trigger the development of autoimmune rheumatic diseases in some patients,” said speaker Ami Shah, MD, MHS. “Preliminary work in diseases like scleroderma and myositis illustrates that naturally occurring anti-tumor immune responses may lead to autoimmunity. One question is whether new oncology agents that are designed to trigger robust anti-tumor immune responses can also lead to rheumatic disease through similar mechanisms.”

Despite the potentially harmful rheumatic side effects of new cancer drugs, the speakers said there are currently more questions than answers. However, careful screening may be beneficial for some patients with rheumatic conditions triggered by cancer, according to the session.

“We are learning that at least some of our autoimmune diseases could be triggered by underlying cancers and the immune responses that develop in response to cancer,” Dr Shah said. “That may have important implications for how we screen for cancer and treat our traditional rheumatologic diseases.”

While patients may develop an autoimmune condition related to cancer therapy, the speakers noted that few rheumatologists have observed these cases due to the novelty of immunotherapy. As immunotherapy gains in popularity, they expect to see more cases of rheumatic conditions related to cancer.

“A new class of cancer agents, immune checkpoint inhibitors, can cause rheumatic disease, and we have minimal guidance for either evaluation or treatment,” said speaker Laura Cappelli, MD, MHS. “Some of the consequences of these new agents look like our more classic rheumatic disease, from rheumatoid arthritis to a Sjögren’s-like syndrome, vasculitis, myositis, and other inflammatory adverse events.”

Current immunotherapies are checkpoint inhibitors that target programmed cell death-1 (PD-1) receptors, PD-1 ligand receptors, and cytotoxic T-lymphocyte-associated antigen 4. The speakers said that many of these drugs have a high rate of immune-mediated adverse events.

Rheumatologists expect to see more cases of inflammatory conditions caused by cancer therapy in the coming years, which calls for oncologists to become more informed about immune-related events.

The speakers said that because oncologists understand that rheumatologists are much more capable of managing musculoskeletal problems and rheumatic symptoms, patients will be directed to the proper specialist, according to the session.

“We all need to be more familiar with the different autoimmune syndromes that can happen as a result of cancer immunotherapy and how we approach evaluating and managing these patients,” Dr Cappelli said. “We also need to consider the effects of checkpoint inhibitors in our patients with preexisting autoimmune disease and how we can work with oncologists to ensure that these patients have the best possible outcomes for both their cancer and their autoimmune disease.”