Corticosteroid, DMARD use increase skin cancer risk in patients with RA
Patients with rheumatoid arthritis demonstrated a significantly increased risk for non-melanoma skin cancer, particularly those treated with higher cumulative doses of corticosteroids and methotrexate, as well as more types of disease-modifying anti-rheumatic drugs, according to findings published in Clinical and Experimental Rheumatology.
This association was also reported among patients treated with cyclosporine, d-penicillamine and etanercept (Enbrel, Amgen), and was much stronger among elderly patients.
“Several clinical studies have reported that the patients with RA had increasing incidences of malignancies, particularly lymphoma,” Hui-Wen Tseng, MD, MOH, of Kaohsiung Veterans General Hospital, Taiwan, told Healio Rhuematology. “The patients with RA using TNF inhibitors and prednisone therapy have been reported to be associated with skin cancer. We investigated this association in a Taiwan population.”
To evaluate the effects of certain treatments, including corticosteroids and disease-modifying anti-rheumatic drugs (DMARDs), on the link between RA and non-melanoma skin cancer, the researchers conducted a nationwide retrospective case-control study of the Taiwan National Health Insurance Research Database. Focusing on data from 1995 to 2013, the researchers matched 19,603 cases of newly-diagnosed non-melanoma skin cancer with patients without skin cancer in a control group on a 1:1 ratio, on the basis of age, sex and reference date.
The researchers used conditional logistic regression to analyze the associations between RA and non-melanoma skin cancer, adjusting for age, sex, geographical region, occupation and comorbidities. They also took special note that case-control studies cannot demonstrate causality.
According to the researchers, patients with RA had a significantly higher association with non-melanoma skin cancer (adjusted OR =2.23; 95% CI, 1.6-3.1) compared with those without RA (P < .001). That association was especially significant among RA patients who received cyclosporine (aOR = 5.7; 95% CI, 2.2-14.86), etanercept (aOR = 5.27; 95% CI, 1.15-24.27) and d-penicillamine (aOR = 4.79; 95% CI, 1.63-14.12). These effects were strengthened among patients aged 65 years and older (cyclosporine, aOR = 7.28 [95% CI, 2.16-24.56]; etanercept, aOR = 8.95 [95% CI, 1.12-71.85]; and d-penicillamine, aOR = 3.81 [95% CI, 1.26-11.52]).
The association between RA and non-melanoma skin cancer was also particularly significant in patients treated with cumulative doses of more than 10 g of corticosteroids (aOR = 2.96; 95% CI, 1.67-5.22) and more than 3 g of methotrexate (aOR = 4.64; 95% CI, 1.74-12.4). These effects were also more pronounced in patients aged 65 and older (corticosteroids, aOR = 3.5 [95% CI, 1.77-6.92]; methotrexate, aOR = 10.17 [95% CI, 2.34-44.26]).
Lastly, patients using more kinds of DMARDs also demonstrated an increased association, including those receiving any three (aOR = 3.72; 95% CI, 1.67-8.26), any five (aOR = 2.81; 95% CI, 1.13-7.04), any six (aOR = 5.23; 95% CI, 1.14-24.14) and any seven or eight (aOR = 4.06; 95% CI, 1.14-14.49).
“Patients with RA, especially elderly with long-term treatment, must be screened for skin cancer during daily practice,” Tseng said. – by Jason Laday
Disclosure: The researchers report no relevant financial disclosures.