[Clinical characteristics and treatment outcome of 36 cases with non-Hodgkin's lymphoma arising from mediastinum in children].

OBJECTIVE: Non-Hodgkin's lymphoma (NHL) presenting as mediastinal mass is usually progressive and may cause severe respiratory distress and death. This study aimed to summarize the clinical features and prognosis of NHL arising from mediastinum. METHODS: Totally 36 patients with NHL arising from mediastinum reported herein were diagnosed between 1999 and 2007. Their clinical characteristics, pathologic classification, diagnosis, outcome of different treatment protocol were retrospectively analyzed. Of these 36 patients, 25 were male, 11 were female (2.2:1). The mean age was 7.9 (range 1 - 12) years. Diagnosis was established on pathology that was achieved by mediastinal mass or peripheral lymph nodes biopsy, while some were diagnosed based on bone marrow or pleural effusion cytology study and immunophenotyping. For staging, the St. Jude system was applied. Patients received T-NHL-CCCG97, T-NHL-2002 or B-NHL-2001 protocol according to morphology and immunophenotyping. Patients who experienced superior vena cava syndrome (SVCS) and/or superior mediastinum syndrome (SMS) received induction chemotherapy with cyclophosphamide (C), vincristine (O) and prednisone (P) for one week. RESULTS: Twenty-seven cases experienced mediastinal mass or peripheral lympho nodes biopsy and were diagnosed by histopathology and immunohistochemistry. Of them, 24 were lymphoblastic lymphoma and 3 were anaplastic large cell lymphoma. Nine patients were diagnosed by cytological study of bone marrow aspiration or pleural fluid. All the 36 cases were T-cell type. Twenty-four cases were in stage III, 12 in stage IV. Twenty-four patients had urgent situation of SVCS and airway obstruction, 22 patients reached good response after emergency management including COP induction chemotherapy and pleural effusion suction. Twenty-nine cases achieved complete remission (CR) while in 6 patients the disease relapsed. Thirteen patients died from disease progression, relapse or severe infection during chemotherapy. The Kaplan-Meier estimate of 5-year progression-free survival (PFS) was 61% +/- 8% (median follow up 35 months) for these 36 patients. CONCLUSION: Establishment of a diagnosis as soon as possible was important to reduce the mortality and improve long term survival of patients. Induction chemotherapy for emergency situation was efficacious. The regimen of T-NHL-CCCG97, T-NHL-2002, and B-NHL-2001 for NHL arising from mediastinum based on pathological classification is feasible.