IntroductionPrimary cutaneous lymphomas (CLs) represent the second most common extranodal group of non-Hodgkin lymphomas and are characterized by an accumulation of clonal T or B lymphocytes preferentially homing to the skin (1). Most CLs are indolent diseases with good prognosis that display a chronic course, sometimes progressing over decades. This in turn creates an increasing need for treatment modalities that would effectively control the disease for a longer time period together with showing good tolerability. Immunotherapy is one such solution that currently belongs to the standard therapeutic armamentarium. The use of recombinant cytokines has found its rationale in the immunobiology of this disease group and aims to enhance antitumor immunity (1, 2). As an alternative to recombinant cytokines that are often associated with significant systemic side effects, we recently described adenovirusmediated (Ad-mediated) delivery of human IFN-γ gene directly into CL lesions, showing good tolerability together with promising efficacy (3). Adenoviral vectors belong to the most frequently used gene delivery systems due to their ability to transduce a broad spectrum of cells and package large sequences and their low production costs (4). The fact that they do not integrate into the host genome has made them attractive in cancer immunotherapy, where only