Biologics Do Not Increase Melanoma Risk in Patients With Inflammatory Disease

Findings of a systematic review and meta-analysis showed there was no significant association in the increase in melanoma risk in those treated with biologic therapy for common inflammatory diseases compared to those treated with conventional systemic therapy alone.

Shamarke Esse, a PhD student, and colleagues examined whether biologic treatment of inflammatory bowel disease (IBD), rheumatoid arthritis, or psoriasis was associated with an increased risk of melanoma compared with conventional systemic therapy. The investigators searched Embase, MEDLINE, and the Cochrane Central Register of Controlled Trials for articles published from January 1, 1995-February 7, 2019 for eligible studies.

The team identified randomized clinical trials, open-label extension trials, cohort studies, and nested case-control studies comparing the risk of melanoma in patients with IBD, rheumatoid arthritis, or psoriasis. Studies were eligible for inclusion if patients were treated with biologic therapy for >12 months and were compared with biologic-naïve patients with similar clinical and disease characteristics treated with conventional systemic therapy alone.

The investigators extracted the lead author and year of the study publication, the study design, and source population and baseline demographics. They also collected the type(s) of biologic therapy, comparator therapy, treatment durations, follow-up period, outcomes, and quantitative estimates with 95% CIs.

Overall, the team identified 1532 records and, after title screening, removed an additional 1363. Additional records were removed, leaving only 7 eligible for analysis.

Among the 7 studies included, they were published between 2007-2019 and were cohort studies conducted in the US (3 studies), Denmark (2 studies), Sweden (1 study), and Australia (1 study). A majority of the studies (4) were conducted with patients with rheumatoid arthritis, while 2 had IBD patients and 1 had patients with psoriasis.

A total of 34,029 patients received biologic treatment and 135,370 biologic-naïve patients received conventional systemic therapy. The mean patient follow-up duration ranged from 1-5.48 years.

Compared with conventional systemic therapy, the pooled relative risk estimates for patients treated with biologic therapy were 1.2 (95% CI, .6-2.4) for patients with IBD and 1.2 (95% CI, .83- 1.74) for patients with rheumatoid arthritis. The relative risk estimate for patients with rheumatoid arthritis treated only with tumor necrosis factor inhibitors compared to those with conventional systemic therapy was 1.08 (95% CI, .81-1.43).

When the investigators compared with biologic-naïve patients who received conventional systemic therapy, the relative risk of melanoma among rituximab-treated patients with rheumatoid arthritis was .73 (95% CI, .38-1.39) and the risk among abatacept-treated patients with rheumatoid arthritis was 1.43 (95% CI, .66-3.09).

The systematic review and meta-analysis did not yield a significantly significant association between biologic exposure and the development of melanoma in patients with IBD, rheumatoid arthritis, or psoriasis compared with those who received conventional systemic therapy. The investigators believed there is a need for a larger, well-designed study to help improve certainty.

The team recommended prospective cohort studies using an active-comparator, new-user study design with treatment history, concomitant treatment, duration, UV exposure and diagnoses to get a better, more clear result. The studies would need to account for key risk factors and the latency period of melanoma.

The study, “Melanoma Risk in Patients Treated With Biologic Therapy for Common Inflammatory Diseases,” was published online in JAMA Dermatology.