Clinical Profile and Therapeutic Aspects of Mycosis Fungoides: a Retrospective Analysis of 210 Cases in Russia

Background. Mycosis fungoides (MF) is classified as an orphan disease. Due to the rarity of pathology, and until recently the absence of an expert group and a specialized reference center for cutaneous lymphomas in Russia, possible treatment options for MF are presented by listing them without recommendations on the preferred indications for one or another option. This creates difficulties in choosing treatment methods and assessing their effectiveness.Aim. To characterize current treatment methods and their results in MF patients who were observed or received consultative and diagnostic care at the National Medical Research Center for Hematology.Materials and methods. The study included 210 patients: 115 with early disease stages and 95 with advanced stages.Results and conclusion. The most common treatment options were for early stages – local therapy, interferon therapy and systemic chemotherapy (CT), for advanced stages – combination therapy with interferon (+ PUVA therapy, methotrexate), interferon monotherapy and systemic CT. The frequency of systemic chemotherapy use in all lines of MF treatment was 21 %. When integrating statistical analysis using the probability of achieving an antitumor response, switching to 2nd line therapy, and accumulated incidence, the negative results of using chemotherapy in the MF treatment were clearly demonstrated.For the first time in Russia, a real practical situation of the applied MF treatment options is presented on our own large sample of patients. As the first line of therapy, the most common options were immunotherapy and phototherapy, however, in 12.4 % of cases, the use of systemic CT was registered, which is unjustified and leads to a decrease in the time to the next line of treatment and an increase in the cumulative incidence of adverse events. As a result of the use of non-chemotherapeutic approaches (interferon, etc.), the 3-year relapse-free survival rate is about 40 %, after chemotherapy – 9.4 %. Secondand third-line therapy provided more varied options, including combination treatment with interferon and methotrexate, as well as gemcitabine monotherapy, targeted therapy with brentuximab vedotin, and epigenetic therapy in the 3rd line. Studies with targeted agents in this patient population have demonstrated improved clinical outcomes, highlighting the need for their early use to achieve the best results.