Cutaneous Lymphomas

Primary cutaneous lymphomas are the second most common form of extra-nodal lymphomas. They have special characteristics compared with other lymphomas. They are most frequently of T-cell origin and they generally have a much more indolent course than lymphomas of similar histology in other locations. Mycosis fungoides is the most common type of cutaneous lymphoma. Primary cutaneous lymphomas remain confined to the skin for a long time. Skin-directed therapies are the main treatments; systemic treatments are not very effective for the skin lesions. Skin-directed therapies used for the early and thin lesions are topical corticosteroids, phototherapy and topical retinoids and, for the more widespread or thick lesions, topical nitrogen mustard and radiation. Radiation therapy is highly effective and is indicated in virtually all cases of localised disease. Radiation therapy may be given to the whole skin surface, so-called total skin electron beam therapy. However, if the disease spreads to other organs, systemic treatments are indicated, often combined with skin-directed therapies. Conventional cytotoxic therapy is less effective in cutaneous lymphomas. The commonly used therapies, such as interferon, enhanced anti-tumour immunity and the recent advances in immune therapies may improve our treatments for cutaneous lymphomas. (C) 2019 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.