Mycosis fungoides (MF), the most prevalent cutaneous T-cell lymphoma, is characterized by malignant T-cell proliferation within a chronic inflammatory environment with variable disease progression from indolent to aggressive forms. Our hypothesis is that the interaction between malignant and reactive T cells in MF lesions is influenced by the microbiome, thereby affecting disease progression. Our research aims to link these interactions with the microbiome to identify prognostic markers and develop novel therapies.