Abstract: Objective: To analyze the clinical characteristics, diagnostic criteria and treatment methods of the children with degenerative large cell lymphoma (ALCL), and to improve the diagnosis and treatment level of the clinicians. Methods: The clinical data of one child with ALCL were retrospectively analyzed, including clinical symptoms, signs, auxiliary examination, diagnosis basis, differential diagnosis, treatment plan and disease outcome,and the key factors of diagnosis and treatment of the disease were summarized combined with literature review. Results: The child went to hospital because of progressive lymph node enlargement as the first symptom. The lips were red, the epidermis was cleft, the skin was dry, both hands were prominent, and the palm was cleft and the flaky desquamation was visible on the fingertips;multiple swollen lymph nodes were found on the sides of neck, the boundary was unclear, the activity was poor,and tenderness was also found; the tongue nipple presented strawberry tongue. The biopsy pathological results showed ALK-positive ALCL. There were no abnormalities in the bone marrow smear; the abnormal phenotypic T lymphocytes were found in the bone marrow immunotype, peripheral blood immunotype and cerebrospinal fluid immunotype. According to the International Childhood Non-Hodgkin's Lymphoma Staging System (2012),the chlid was clearly diagnosed as ALK-positive ALCL (stage Ⅳ, R3 group).After the induction chemotherapy of APO regimen was given, the condition of the patient was up to partial remission(PR),and the treatment regimen was replaced with B-NHL-BFM-90 regimen; after one cycle of modified AA regimen, the bone marrow and peripheral blood immunotype of the patient turned negative. Conclusion: The clinical manifestations of ALCL patients are different; the lymph node biopsy is the only basis for the diagnosis of ALCL,and hormones could not be blindly used before definitive diagnosis.

Key words: biopsy, bone marrow immunotype, anaplastic lymphoma kinase, anaplastic large cell lymphoma, T lymphocyte, lymph node