Treatment of lupus may raise cervical cancer risk

Women with the autoimmune disorder systemic lupus erythematosus (SLE) seem to have a heightened risk for cervical cancer when they're been treated with the immune-suppressing drug cyclophosphamide, according to a new study.

In fact, women treated with other immunosuppressive drugs should also "be considered potentially at higher risk," Dr. W. Joseph McCune from University of Michigan Health System, Ann Arbor, told AMN Health.

McCune and his colleagues monitored the occurrence of a precancerous condition called cervical intraepithelial neoplasia, or CIN, over a 3-year period among in 61 women with lupus who were treated with injections of cyclophosphamide and/or azathioprine plus prednisone.

Six women treated with cyclophosphamide alone or in combination with azathioprine developed CIN, the team reports in the Journal of Rheumatology, compared with none of the women treated only with prednisone alone or azathioprine plus prednisone.

Compared with the general population, the rate of CIN was three times higher for women with SLE who were given cyclophosphamide.

Only two additional patients developed abnormal cervical smears in the following 4 years, neither of which showed CIN, the researchers note.

"The frequency of monitoring probably should be increased in high-risk women, but there are no data to support a particular approach," McCune advised.

Also, his study did not look at whether the type of human papilloma virus (the cause of nearly all cases of cervical cancer) harbored by the women played into their risk for developing CIN. In general, certain virus subtypes are known to be more virulent than others.

The next step to clarify the causal role of cyclophosphamide "would be to serotype HPV in women starting treatment," McCune added.

SOURCE: Journal of Rheumatology, September 2004.