An old term for a chronic eruption of the skin characterised by erythematous (see ERYTHEMA) itching plaques (raised patches on the skin resulting from the merging or enlargement of papules) (see PAPULE), which, if left untreated, eventually form tumours and ulcers. The disease is now known to be a form of cancer of lymphocytes (see LYMPHOCYTE) called T-cell LYMPHOMA. It may be responsive to PHOTOCHEMOTHERAPY in its early stages and to RADIOTHERAPY when more advanced.