Do Biologics Increase Melanoma Risk? Jury May Still Be Out

Patients with inflammatory diseases such as rheumatoid arthritis (RA), psoriasis, and inflammatory bowel disease (IBD) are often placed on biologic therapies for treatment. Questions have been asked about whether long-term biologic treatment, versus conventional systemic therapy treatment, could increase the risk for melanoma. A new systematic review and meta-analysis sought to identify the risk and concluded that biologics may—or may not—increase this risk.

The researchers queried Embase, MEDLINE, and the Cochrane Central Register of Controlled Trials for relevant trials published between Jan. 1, 1995, and Feb. 7, 2019, that quantified melanoma risk in IBD, RA, and psoriasis patients treated with biologics versus conventional systemic therapy. Eligibility criteria included randomized clinical trials, cohort studies, and nested case-control studies. Articles were assessed by two independent reviewers. The main outcome was the pooled relative risk (pRR) of melanoma compared between the biologic- versus conventional systemic therapy-treated IBD, RA, and psoriasis patients.

A total of seven eligible cohort studies were included, encompassing 34,029 biologic-treated patients and 135,370 biologic-naïve patients treated with conventional systemic therapy. Biologic treatment, compared to conventional systemic therapy treatment, was correlated with melanoma in IBD (pRR, 1.20; 95% CI, 0.60-2.40), RA (pRR, 1.20; 95% CI, 0.83-1.74), or psoriasis (hazard ratio, 1.57; 95% CI, 0.61-4.09), although the differences did not reach statistical significance. Most studies did not adjust for other risk factors, the authors noted.

The study was published in JAMA Dermatology.

“The findings suggest that clinically important increases in melanoma risk in patients treated with biologic therapy for common inflammatory diseases cannot be ruled out based on current evidence. However, further studies with large patient numbers that adjust for key risk factors are needed to resolve the issue of long-term safety of biologic therapy,” the researchers summarized.