Is there truly a risk of lymphoma from biologic therapies?

The treatment of psoriasis has undergone a revolution with the advent of biologic therapies, including infliximab, etanercept, adalimumab, efalizumab, and alefacept. Biologics are generally safe and well tolerated. However, there has been concern over the risk of lymphoma with use of these agents because of their immunosuppressive properties. This review summarizes the current evidence in regards to lymphoma risk with biologic therapy obtained from case reports and case series, observational studies, clinical trials, and meta-analyses. The majority of data for T-cell inhibitors comes from case reports and relatively small, short-term clinical trials. In addition to published case reports and case series, TNF-alpha inhibitors have also been studied extensively in large cohort studies and meta-analyses of clinical trials derived primarily from the rheumatoid arthritis population. Current data are neither sufficient to completely rule out an increased risk of lymphoma associated with biologics, nor to firmly establish a causal relationship between biologics and lymphoma. Short- to intermediate-term treatment with biologics (e.g., up to 4 years) appears to be very safe with respect to lymphoma risk, especially with TNF-alpha inhibitors in which their potential risks appear to be well defined. Continued vigilance is warranted; however, in the appropriate patient, the risk-to-benefit profile of psoriasis treatment with respect to lymphoma risk appears highly favorable.