Systemic Lupus Erythematosus (SLE), commonly known as lupus, is a long-term autoimmune disease where the body’s immune system mistakenly attacks its own healthy tissues and organs. This can lead to inflammation and damage in various parts of the body, including the skin, joints, kidneys, and brain. Understanding the potential relationship between lupus and cancer risk is a common concern. This article explores this connection.
Understanding the Connection Between Lupus and Cancer
There is an elevated risk of certain cancers in individuals with lupus compared to the general population. This association is complex, indicating that while overall cancer risk is increased, it is not uniformly high across all cancer types. This connection is not a straightforward cause-and-effect, but rather a nuanced interplay of factors inherent to lupus. Studies have shown an increased overall cancer risk in patients with SLE, with one meta-analysis indicating a 62% elevated risk of overall cancer morbidity and a 52% increased risk of cancer-related death.
Types of Cancer Associated with Lupus
Individuals with lupus have a consistently linked increased risk for certain types of cancer. Hematological malignancies, such as lymphomas, particularly non-Hodgkin lymphoma (NHL) and Hodgkin lymphoma (HL), are more common in lupus patients. The risk of lymphoma can be elevated by as much as four to seven times compared to the general population.
Beyond blood cancers, several solid tumors also show an increased incidence in those with lupus. These include:
- Lung cancer
- Liver cancer
- Cervical cancer
- Non-melanoma skin cancer
- Thyroid cancer
- Esophageal cancer
- Stomach cancer
- Kidney cancer
- Bladder cancer
- Pharynx cancer
- Larynx cancer
Some studies also indicate an elevated risk of endometrial cancer.
Underlying Reasons for Increased Risk
The elevated cancer risk in lupus patients is attributed to several proposed mechanisms. Chronic inflammation, a hallmark of lupus, plays a significant role as persistent inflammation can promote cellular changes that lead to cancer development. The immune dysregulation inherent in lupus, where the immune system malfunctions, may also contribute by impairing the body’s natural ability to detect and eliminate abnormal cells before they become cancerous.
The long-term use of certain immunosuppressive medications is another contributing factor. Drugs like azathioprine and cyclophosphamide, commonly used to manage lupus, can suppress the immune system’s surveillance capabilities, potentially increasing the risk of some cancers. This effect may become more apparent five or more years after starting these medications, particularly for lymphomas and other blood cancers. Viral infections, such as human papillomavirus (HPV) and Epstein-Barr virus (EBV), can also contribute, as individuals with compromised immune systems may be more susceptible to persistent infections that are known to promote cancer development.
Monitoring and Risk Reduction Strategies
Regular cancer screenings are important for individuals with lupus for early detection. This includes routine skin checks, given the elevated risk of non-melanoma skin cancers, and cervical cancer screenings, such as Pap tests, due to the increased risk of cervical cancer in lupus patients. Age-appropriate general cancer screenings, as recommended for the general population, should also be followed.
Managing lupus disease activity effectively helps reduce chronic inflammation, which is a known contributor to cancer risk. Patients should engage in open discussions with their healthcare providers regarding the potential risks and benefits of their medications, especially immunosuppressants, to ensure informed treatment decisions. Adopting healthy lifestyle choices is also beneficial, including smoking cessation, consistent sun protection, and maintaining a balanced diet, all of which can contribute to overall health and potentially reduce cancer risk. It is important to communicate any new or persistent symptoms to the healthcare team promptly for evaluation.