Frequency of Malignant Neoplasms in 248 Long-Term Methotrexate-Treated Psoriatics

Abstract

The frequency of malignant neoplasms was studied in 248 psoriatics treated with a single, weekly, oral dose of methotrexate ranging from 5 to 25 mg. The follow-up period ranged from 5 to 14 years with a median of 7 years. The following 10 malignant neoplasms were found: ovarian cancer 3, breast cancer 2, esophageal cancer in 1 male, pancreatic cancer in 1 female, malignant lymphoma in 1 female and 1 male and 1 squamous cell carcinoma of the scrotal skin. As the observed number of malignant neoplasms was considerably smaller than the expected number, it is concluded that methotrexate therapy as used in the treatment of psoriasis does not seem to contribute to the development of malignant neoplasms.

Three cases of malignant neoplasm, pneumonitis, and pancytopenia during treatment with low-dose methotrexate

“…The possibility of methotrexate carcinogenicity due to its immunosuppressive action has been discussed [8,12,13], and single cases of malignant neoplasm during low-dose treatment have been described [5], mainly after several years of treatment. In addition, folate deficiency induced by methotrexate can be carcinogenic [19].…”

“…In addition, folate deficiency induced by methotrexate can be carcinogenic [19]. However, the only larger follow-up study of 248 patients with psoriasis receiving low-dose methotrexate (5-25 mg per week) [13] revealed only 9 malignant neoplasms (as compared to the statistically expected number of 22). Therefore, contrary to our clinical experience (cases 1-3), the limited epidemiological data do not show a clearcut carcinogenic effect of low-dose methotrexate.…”

Methotrexate in rheumatoid arthritis

“…No evidence of MTX-induced carcinogenicity has been found in rats, and its carcinogenicity in mice and hamsters could not be evaluated, according to the International Agency for Research of Cancer, a division of the World Health Organization (67). There have been a few case reports of carcinomas or lymphomas occurring in RA or psoriasis patients given low-dose methotrexate (73)(74)(75). In contrast, no increase in malignant neoplasms was found in 3,522 patient-years-of-risk in patients given MTX for choriocarcinoma, or in 248 psoriasis patients given long-term MTX treatment (75,76).…”

Golimumab and malignancies: true or false association?

“…Some studies suggest lymphoma risk after biological therapy [3,30,31], but the cumulative incidence of lymphoma, throughout 248 long-term MTX-treated psoriatics cases, is not expected to be much higher than 1% [28,32]. Recent systematic reviews, performed on MTX-treated patients with RA, suggest that there is no sufficient data to assess the risk of lymphoma and also malignancies [33,34].…”