Blood cancer risk increased with lupus drugs

NEW YORK (Reuters Health) - The results of a new study provide more evidence that the immune-suppressing drugs used to treat lupus may increase the risk of leukemia and other blood, or "hematologic," cancers.

In lupus and several other autoimmune diseases, in which the body attacks itself, there is "increasing evidence" that cancer, particularly hematologic and lung cancers, is a common cause of death and other serious complications, the study team notes.

To investigate further, Dr. Sasha Bernatsky of McGill University Health Centre in Montreal, and colleagues conducted a study using an international group of lupus patients. They focused on 246 patients with cancer, which included 46 with hematologic cancer and 35 with lung cancer, and 538 patients without cancer.

According to their report in the Annals of the Rheumatic Diseases, the overall cancer risk with lupus was increased with older age and with more severe lupus damage. For lung cancer, smoking also appeared to be a risk factor, as expected.

In addition, the results suggested that immune-suppressing drugs may increase the risk of blood cancer, but not lung, cancer. In one analysis, the use of such drugs more than doubled the risk of hematologic cancers.

"Our results set the stage for future evaluations of long-term effects of emerging agents" for the treatment of lupus that are not associated with an increased risk of cancer, Bernatsky and colleagues add.

SOURCE: Annals of the Rheumatic Diseases, January 2008.