Difficulties in diagnosing ALK-negative anaplastic large cell lymphoma manifesting from a skin lesion

Anaplastic large cell lymphoma is a rare form of non-Hodgkin's lymphoma that requires an early diagnosis and urgent therapy due to aggressive tumor process. Clinically, most non-Hodgkin's lymphoma present with lymphoadenopathy and В-symptoms (such as weakness, drowsiness, fatigue, subfebrile fever, profuse night sweats). However, anaplastic large cell lymphoma may present with nonspecific skin lesions with minimal or no B-symptoms. The skin lesions are heterogeneous, which may also delay verification of the diagnosis. We present a case of widespread anaplastic large cell lymphoma skin lesions mimicking a case of erysipelas, which progressed rapidly from a single rash on the wrist to an extensive lesion of the right breast within 1 month. Prior to verification of the diagnosis, the patient was treated for erysipelas, pyoderma, and herpes zoster with no response to therapy. Immunohistochemical examination of a skin biopsy confirmed the diagnosis of ALK-negative anaplastic large cell lymphoma. At the time of publication, the patient had completed 1 course of the CHOEP regimen, and 6 cycles of the program were planned. Our case demonstrates the necessity of a broad differential diagnosis of rashes torpid to the current therapy.