Leukemic phase of ALK-negative anaplastic large cell lymphoma presenting as leukostasis: the first case report in Thailand

Anaplastic large cell lymphoma (ALCL) is an aggressive T-cell lymphoma characterized by hallmark cells that are CD30-positive. ALCL is subcategorized as anaplastic lymphoma kinase (ALK)-positive and ALK-negative types. The leukemic phase of ALK-negative ALCL is extremely rare and usually has a poor prognosis. We report the first case of the leukemic phase of ALK-negative ALCL in Thailand. A 60-year-old man presented bilateral cervical lymphadenopathy and night sweats for 6 months. He was admitted to the hospital with acute fever, progressive dyspnea on exertion, severe headache and blurred vision. His complete blood count revealed marked leukocytosis (352.5 x 109/L) with numerous atypical medium- to large-sized mononuclear cells. The results of his laboratory investigations were compatible with spontaneous tumor lysis syndrome and disseminated intravascular coagulation. The flow cytometry analysis from bone marrow aspiration along with histopathologic findings and immunohistochemistry from bone marrow study were consistent with ALK-negative ALCL. The patient was treated with leukapheresis, renal replacement therapy and high-dose dexamethasone. After achieving hemodynamic stability, a computed tomography scan of the brain was performed due to persistent alteration of consciousness. The results showed extensive intracerebral hemorrhage with severe brain edema and tonsillar herniation. Due to this complication, the treatment plan was adjusted to palliative care with supportive treatment after discussion with his family. The patient subsequently passed away from septic shock.