Pagetoid reticulosis with a keloid-like appearance

A 31-year-old Vietnamese woman presented with a 10-year history of asymptomatic plaques on her left ankle that had slowly increased in size. She denied prior trauma to this area. The lesion did not respond to topical corticosteroid treatment. Her general health was good without other diseases and she was not taking any medication. On examination, two erythematous, welldemarcated plaques with an irregular edge were seen on her left ankle (Figure 1A and B). The clinical appearance was similar to a keloid. Histological examination revealed a strikingly epidermotropic infiltrate of medium-sized atypical lymphoid cells (Figure 2A). The atypical cells, demonstrating pagetoid spread, had hyperchromatic nuclei and a perilymphocyte halo (Figure 2B). Aggregation of atypical cells into Pautrier’s microabscess was also noted. The papillary dermis was fibrotic and contained a band-like infiltrate of small lymphocytes and few atypical lymphoid cells. Immunohistochemical studies showed that most of these atypical cells in the epidermis were positive for CD30 (Figure 2C), weakly positive for CD4, and negative for CD7, CD8, and CD79a. The small lymphocytes that had infiltrated the papillary dermis were positive for CD4 or CD8, but negative for CD30. A systemic workup was negative for other sites of involvement and the results of laboratory examinations were within normal limits. The patient’s lesion was most consistent with a diagnosis of PR. Our patient was treated with local electron-beam radiotherapy to her left ankle to a total of 40 Gy in 2-Gy fractions over a 2month period. The skin lesions became much thinner and smaller