A Case of Primary Cutaneous Anaplastic Large Cell Lymphoma Mimmicking Keratoacanthoma / 대한피부과학회지

ABSTRACT

Pseudoepitheliomatous hyperplasia with a massive neutrophil infiltrate associated with primary cutaneous anaplastic large cell lymphoma has been rarely reported. Herein we report on a 33-year-old man who presented with multiple asymptomatic erythematous walnut-sized rapidly growing tumors on the axilla, trunk and left inguinal area for 1 month. The histopathologic features showed a keratoacanthoma-like epithelial hyperplasia in the epidermis and several large atypical lymphoid cells with nuclear plemorphism and abundant cytoplasm in the dermis. The atypical cells were obscured by a rich infiltrate of neutrophils and some eosionophils. Immunohistochemical studies confirmed the majority of the large anaplastic cells in the dermis were CD30+ cells. In addition, the expressions of anaplastic lymphoma kinase (ALK) and epithelial membrane antigen (EMA) were negative. There was no evidence of extracutaneous involvement. The patient was diagnosed with primary cutaneous anaplastic large cell lymphoma (ALCL) and he was treated with low dose methotrexate (15 mg/week). We think that this case was challenging both clinically and histologically.