Benefit/risk Ratio of Low-dose Methotrexate in Cutaneous Lesions of Mycosis Fungoides and Sézary Syndrome

Low-dose methotrexate is widely used in mycosis fungoides and Sézary syndrome, but few studies have evaluated this treatment. The aim of this study was to evaluate the benefit/risk ratio of this regimen on skin lesions. A retrospective survey of a series of patients treated for mycosis fungoides or Sézary syndrome with low-dose methotrexate and followed for at least one year in a tertiary referral centre was performed. From a total of 48 patients, complete response and partial response were achieved in 10 (21%) and 25 (52%) patients, respectively, with no significant difference in response rates between mycosis fungoides and Sézary syndrome. Of the responders, 20 out of 35 (57%) relapsed after a median time of 11 months. Forty-four of the total of 48 patients discontinued methotrexate, mainly due to primary or secondary failure and/or limiting toxicity (9 patients). Overall, the benefit/risk ratio of low-dose methotrexate in mycosis fungoides and Sézary syndrome appears favorable and this treatment remains a valid option in mycosis fungoides/Sézary syndrome. However, its activity is limited in duration and significant toxicity may occur in some patients.