Through thick and thin: confronting the aggressive cutaneous T-cell lymphomas

The cutaneous T-cell lymphomas (CTCLs) comprise a diverse set of diseases with equally diverse presentations ranging from asymptomatic solitary lesions to highly aggressive diseases with propensity for visceral spread. The more aggressive CTCLs, which herein we consider as certain cases of advanced-stage mycosis fungoides/Sézary syndrome (MF/SS), primary cutaneous CD8+ aggressive epidermotropic cytotoxic T-cell lymphoma (PCAETCL), and primary cutaneous gamma delta T-cell lymphoma (PCGDTCL), require systemic therapy. Over the last 5 years, treatment options for MF/SS have expanded with biological insights leading to new therapeutic options and increasingly unique management strategies. An enhanced appreciation of the compartmental efficacy of these agents (skin, blood, lymph nodes, visceral organs) is incorporated in current management strategies in MF/SS. In addition, approaches that combine modalities in attempts to increase depth and durability of responses across multiple compartments are being trialed. In contrast to MF/SS, PCAETCL and PCGDTCL remain diseases with few prospective studies to guide treatment. However, recent genomic insights on these diseases, such as the presence of JAK2 fusions in PCAETCL and cell of origin findings in PCGDTCL, have created options for new biomarker-driven strategies.