Although anti-TNFα agents have revolutionized the treatment of many inflammatory diseases, various concerns have been reported regarding the risks of cancer development, as well as acceleration of the progression of subclinical, preexisting malignancies. In this case series, we investigated the provocative effect of anti-TNFα drugs in the development of cutaneous mycosis fungoides (MF)-like lymphoproliferative reactions. We describe five patients aged between 25-63 diagnosed with autoimmune disorders (psoriatic arthritis - one patient, Crohn's disease - one patient and ankylosing spondylitis - three patients) who received anti-TNFα agents before the development of a cutaneous lymphoproliferative reaction. Histological and immunophenotypical analysis was typical for mycosis fungoides in all of them. Anti-TNFα agents were stopped with regression of the skin rash. A direct effect of anti-TNFα agents in the development of lymphoproliferative reactions (including MF) is suggested and further analyzed. Treatment cessation can be therapeutic.