Immunosuppressants associated with modestly increased risk of malignancy

Douglas R. Lazzaro, MD, FACS, FAAO

This article addresses the malignancy risk of medicines used to control ocular inflammation in inflammatory eye disease. The retrospective study looked at data from Australia between 1985 and 2007 in which 58 patients had been on corticosteroids only and 132 patients had been on immunosuppressants only. Most cases with inflammatory eye disease were idiopathic in both groups. Patients with underlying systemic diseases with an increased risk of malignancy were excluded. Median follow-up in the overall cohort was 7.34 years. The absolute and relative rates of de novo malignancy risk were computed for the two treated groups and compared with the general population.

Fifty-five percent of patients were treated with one agent, 28% with two agents, 13% with three and 4% with four. The most commonly used drug was methotrexate, followed by mycophenolate. Twenty-five incident malignancies (two in the steroid group, 23 in the immunosuppressant group) developed in 17 patients during the follow-up period, and the most common ones were nonmelanoma skin cancer. Relative to the general population, the risk of any malignancy in the immunosuppressant group was more than fourfold overall and more than fivefold when excluding the nonmelanoma skin cancer group. The absolute risk of malignancy was increased slightly in both the steroid and immunosuppressant groups, and an excess of 0.89 malignancies per 100 person-years was noted in the immunosuppressant group.

There was no difference in risk between the steroid group and immunosuppressant group when looking at only the first malignancy, but was higher in both the immunosuppressant group (twofold increase) and steroid group (fourfold increase) when multiple malignancies in the same person were counted.