Case for diagnosis.

Ketron-Goodman disease was formerly considered a disseminated type of pagetoid reticulosis. However, according to the new classification consensus, it should be regarded as aggressive epidermotropic CD8 T-cutaneous lymphoma, cutaneous gamma/delta T-lymphoma, or tumor-stage mycosis fungoides, depending on the clinical-histological picture. This case highlights a rare and challenging presentation of Ketron-Goodman disease with an indolent presentation and evolution and good response to a low-grade treatment regimen, not fitting well into the new classification criteria.