Precursor B-cell lymphoblastic lymphoma in childhood and adolescence: clinical features, treatment, and results in trials NHL-BFM 86 and 90

Abstract

Background: Precursor B-cell lymphoblastic lymphoma (PBLL) is a rare subtype of childhood non-Hodgkin lymphoma (NHL). The purpose of our study was to investigate frequency and clinicopathological features of PBLL in children and to test prospectively the efficacy of an ALL-type therapy for treatment of these patients.

Procedure: From October, 1986, to March, 1995, 1,075 patients up to 18 years of age suffering from all kinds of NHL were registered in the two consecutive multicenter studies NHL-BFM 86 and 90. Of these, 27 patients were diagnosed with PBLL. Twenty-one PBLL patients were treated according to a BFM-ALL-type protocol: an eight-drug induction over 9 weeks was followed by an 8-week consolidation including methotrexate 5 g/m(2) x4. Patients in stages I and II continued with maintenance up to a total therapy duration of 24 months, whereas patients in stages III and IV received an additional eight-drug intensification and cranial radiotherapy (12 Gy for prophylaxis) after consolidation. Six PBLL patients were treated according to the BFM-protocol for B-NHL, stratified according to stage and tumor load and consisiting of two to six 5-day courses of chemotherapy.

Results: The median age of the 27 patients with PBLL (18 boys, 9 girls) was 6.2 (range 0.7-15) years. Stages (St. Jude) were: I (n = 3), II (n = 7), III (n = 9), and IV (n = 8). Twenty-one PBLL patients had nodal disease, 6 patients had subcutaneous manifestations, and 8 patients had bone marrow disease (<25% blasts). All patients achieved remission. With a median follow-up time of 4. 25 years, the estimated probability for event-free survival (pEFS) at 10 years for the total group was 0.73 (SE 0.10). Five patients (2, 1, 1, and 1 patients at stages I, II, III, and IV, respectively) relapsed: 2 of 21 patients who were treated according to the ALL strategy and 3 of 6 who were treated according to the B-NHL-protocol.

Conclusions: PBLL accounts for 2.5% of childhood NHL. An ALL-type therapy strategy appears to be superior to a short-pulse B-NHL protocol.