In children, lymphoblastic lymphomas represent 30% of Non-Hodgkin lymphomas (NHL), and approximately 15% are precursor B-cell lymphomas (PBLL). Our study evaluated their main clinical characteristics, evolution, and prognosis in three trials. From 1989 to 2008, 53 children with PBLL (median age 7·75 years) were included in three protocols: Malignant Lymphoma Therapy (LMT) 96, European Organization for Research and Treatment of Cancer (EORTC) 58881, and EORTC 58951 using Berlin-Frankfürt-Münster-derived acute lymphoblastic leukaemia (ALL) therapy. There were 10 stage I disease, 9 stage II, 9 stage III and 25 stage IV. Clinical presentation was heterogeneous with a majority of bone lesions and cutaneous or subcutaneous manifestations. At diagnosis 23 patients had bone marrow involvement, and only three had central nervous system involvement. The median follow-up was 74 months. At last follow-up, 45 patients were in continuous complete remission, whereas eight had progressed or had relapsed (7 Stages IV and 1 Stage III) and died. Two patients had a secondary neoplasia, and are still alive. Disease stage was a major prognostic factor, with better overall survival (OS) and event-free survival (EFS) (P < 0·05) rates observed in patients with Stage I to III as compared to those with Stage IV. Treatment with protocols derived from ALL therapy are efficient with an 82% EFS and an 85% OS at 5 years.