Does Prednisone Cause Cancer?

Some plaintiffs’ lawyers are looking at the question of whether prednisone causes cancer.  Our law firm is not taking prednisone cancer lawsuits, at least not yet.  But we are following the medical literature to see if there are viable lawsuits here.

As lawyers, our role often requires us to evaluate scientific evidence to determine whether it supports viable claims for litigation. Again, this has led to our interest in the relationship between long-term use of prednisone and cancer.

Prednisone

Prednisone, a corticosteroid widely used to treat inflammatory and autoimmune conditions, is one of the most prescribed drugs in the United States. It has transformed the management of diseases such as rheumatoid arthritis, lupus, and asthma due to its potent anti-inflammatory and immunosuppressive properties. It has been a great drug for a lot of people. No one is arguing that. But concerns are mounting about its long-term safety, particularly regarding a potential link to cancer. This article explores the science behind the question, evaluates whether the evidence supports litigation, and discusses the potential future of prednisone cancer lawsuits.

The Science Behind Prednisone and Cancer Risk

Glucocorticoids like prednisone suppress the immune system, which can have dual-edged effects. While this suppression can prevent harmful overreactions in autoimmune conditions, it also reduces the body’s ability to fight off abnormal cells that might otherwise develop into cancer. Studies have shown that prolonged immunosuppression can increase the risk of malignancies, particularly in specific organ systems such as the liver and lungs.

One prominent study that caught our attention was a look at the cancer risks associated with long-term glucocorticoid use in a cohort of over 770,000 individuals. The study’s findings revealed a 23% increased risk of cancer among long-term GC users compared to the general population, with a more pronounced risk for liver and lung cancers. These results were based on individuals prescribed glucocorticoids continuously for 30 days or more, emphasizing the risks of chronic exposure.

It was not a perfect study. Potential confounding factors, such as lifestyle choices (smoking and alcohol use), comorbidities, and socioeconomic status, were not fully accounted for. This raises the question of whether prednisone itself is the direct cause or merely a correlate of increased cancer risk in populations already vulnerable due to underlying conditions requiring glucocorticoid treatment.  Because there is a difference between correlation and association.  Moreover, 23% is significant but it does not jump off the page the way some studies do that trigger litigation (like Depo Provera). But the study definitely caught our attention.

Moreover, looking at cancer is probably looking at it too broadly.  Are there specific cancers that are connected to prednisone?  In that study we just mentioned, the risks were particularly pronounced for liver and lung cancers, with long-term users showing a 46% higher risk of liver cancer and a 52% higher risk of lung cancer.

Evaluating Causation: Does Prednisone Directly Cause Cancer?

In legal terms, causation is central to any potential litigation. To establish a viable case, plaintiffs must demonstrate that prednisone use directly caused their cancer and not merely that it was associated with it. This requires strong scientific evidence, including:

• Epidemiological Studies: Large-scale, peer-reviewed studies showing a significant correlation between prednisone use and cancer.  There is no question we need—and expect to get—more science on this connection.
• Biological Plausibility: A clear mechanism explaining how prednisone contributes to cancer development, such as its immunosuppressive effects or its impact on inflammatory pathways involved in tumorigenesis.
• Dose-Response Relationship: Evidence that higher doses or longer durations of prednisone use correlate with increased cancer risk.
• Exclusion of Confounders: Data accounting for other potential risk factors, ensuring that the observed cancer risk is truly attributable to prednisone.
• The current body of research suggests a plausible link but falls short of definitive proof. While the South Korean study and similar research provide valuable insights, they also highlight the challenges of disentangling prednisone’s effects from the underlying conditions it’s used to treat.

Challenges in Prednisone Cancer Litigation

Several hurdles must be addressed before prednisone cancer lawsuits can move forward. Because there are some headwinds.

• Establishing Causation: As discussed, the current evidence suggests a potential link but lacks the definitive causal proof needed for litigation.  It is hard to argue that a 23% increase is proof positive.
• Preemption Defense: Drug manufacturers often invoke federal preemption, arguing that their products were approved by the FDA and that they complied with all regulatory requirements. Overcoming this defense requires showing that the FDA approval process was flawed or that the manufacturer failed to disclose known risks.
• Statute of Limitations: Many cancer cases involve delayed diagnosis, making it challenging to pinpoint when the statute of limitations begins. Plaintiffs would need to argue for discovery rules that account for the latency period between prednisone use and cancer development.  But, in most jurisdictions, this is not a real issue. If it was, it will kill most of the mass torts our law firm handles.
• Identifying a Cohort of Plaintiffs: Given the relatively low percentage of long-term prednisone users who develop cancer, assembling a substantial group of plaintiffs may be difficult without further scientific support.

Where to Go From Here?

For patients, the potential link between prednisone and cancer underscores the importance of informed consent and shared decision-making with their healthcare providers.  Talk to your doctor about the concerns you have. Doctors should discuss the risks and benefits of long-term prednisone use, exploring alternative treatments where possible. Regular monitoring for signs of cancer, particularly in high-risk populations, is also essential.

For lawyers, the emerging data on prednisone highlights the need to stay abreast of scientific developments to see if anything develops in 2025.  While the current evidence does not yet support widespread litigation, that is how most mass tort lawsuits with big settlements start. We need large-scale studies or meta-analyses that could provide stronger evidence of causation. Putting the card before the horse, at some point lawyers will need to scrutinize pharmaceutical companies’ internal documents through discovery in related cases may reveal whether manufacturers were aware of cancer risks but failed to act. But that requires a lawsuit first so there is a bit of a chicken and the egg problem.

Should stronger evidence of causation emerge, prednisone cancer litigation could follow the trajectory of other pharmaceutical mass torts. For patients and lawyers alike, the priority is to balance the drug’s benefits with its potential risks, advocating for safer, more transparent pharmaceutical practices. While we are not currently accepting prednisone cancer lawsuits, there is no question this area warrants continued attention as the science evolves.