Lupus Linked to Increased Risk of Cancer
Higher Lymphoma Rates Among Systemic Lupus Patients Appears to Drive Trend
Younger Women With Systemic Lupus at Particularly High Risk of Cancer
Compared with the general population, people with systemic lupus were:
- 3.4 times more likely to develop non-Hodgkin's lymphoma
- 3.2 times more likely to develop any lymphoma
- 2.8 times more likely to develop vulvo-vaginal cancers
- 2. 2 times more likely to develop liver cancer
- 1.7 times more likely to develop leukemia
- 1.7 times more likely to develop cervical cancer
- 1.2 times more likely to develop lung cancer
"When stratified by age, people with lupus who are younger than 40 appear to have a particularly high risk. They are 1.7 times more likely to develop cancer than the general population," Bernatsky says.
Drugs, Disease May Drive Tumor Growth in People With Systemic Lupus
The study does not prove cause and effect, and no one knows for sure why people with lupus are at increased risk of certain cancers, Bernatsky says.
"The drugs used to treat lupus may play a role," she says. "But there is just as much evidence that lupus itself may drive tumor growth."
In the case of cervical cancer, "lupus patients are more likely to get precancerous lesions of the cervix and they are less likely to get regular screening because of their disease."
"It's important for these women to get regular Pap smears," Bernatsky says.
People With Arthritis Also Have Higher Cancer Rates
Timothy Beukelman, MD, a rheumatologist at the University of Alabama at Birmingham, tells WebMD that cancer rates are also higher among people with rheumatoid arthritis, compared with the general population.
As with systemic lupus, the immune system is inappropriately turned on in RA, causing inflammation and organ damage, in this case, primarily in the joints.
"In adults with [rheumatoid] arthritis, there is evidence to suggest that both the disease and the drug methotrexate [that is often used to treat it] contribute to an increased risk of malignancy, he says.
More research is needed into the link between cancer and all types of rheumatic disorders, Beukelman says.
This study was presented at a medical conference. The findings should be considered preliminary as they have not yet undergone the "peer review" process, in which outside experts scrutinize the data prior to publication in a medical journal.