Taiwanese Study Links Ankylosing Spondylitis to Higher Risk of Certain Cancers

Ankylosing spondylitis (AS) patients must be screened for certain cancers due to their higher risk, a study from Taiwan warns.

The study, “Ankylosing spondylitis and the risk of cancer,” appeared in the journal Oncology Letters. It aimed to assess whether AS is associated with an increased cancer risk.

AS, a chronic inflammatory disease, is fairly common around the world, affecting mainly young men. It main symptoms are back pain and stiffness in the spine, but AS also affects the heart, lungs, eyes and colon.

Several studies have established that patients with chronic inflammation have an increased risk of developing cancer, since certain proteins — such as cytokines, which are secreted by the body during inflammation — can provide an environment that might trigger malignancies. Yet the current evidence linking AS to cancer has been controversial.

To learn more, a team at Taipei Medical University analyzed data from 5,452 AS patients and 21,808 sex- and age-matched controls without the disease. Researchers collected data between 2000 and 2008 from the Taiwanese National Health Insurance Research Database.

They found that 57.8 percent of AS patients developed cancer within three years of being diagnosed with their AS diagnosis.

Compared to controls, male AS patients had a higher probability of developing bone and prostate cancer, while female patients were more likely to get colon cancer. Both sexes had an equally increased risk of developing hematological malignancies.

Furthermore, AS patients had an earlier onset of cancer than patients with cancer but without AS. Cancer-free survival was also significantly lower in AS patients.

Although the current study had a large sample size and a relatively long follow-up period, it was limited in that the database used did not contain certain key information such as the level of medical attention and biochemical test results. Nevertheless, the study provides evidence to link AS with higher cancer risk.

These findings have important implications for cancer screening in AS patients.

“Tumor screening during the first three years following the diagnosis of AS provides a chance for early detection of hematological malignancies in males and females, prostate cancer in males, and colon cancer in females,” the team said.