Retrospective analysis of relapsed or primary refractory childhood lymphoblastic lymphoma in Japan

To assess the clinical course with response to second-line treatment and to evaluate the role of hematopoietic stem cell transplantation (SCT) in children with relapsed or primary refractory lymphoblastic lymphoma (LBL), we analyzed data of 48 patients with relapsed/primary refractory diseases among 260 LBL patients identified in a national survey of 1996-2004.

Twenty-six patients achieved second complete remission; 9 achieved partial remission. Of 13 patients who showed progression despite first and second line therapy, only one patient was alive on the second relapse after unrelated cord blood transplantation. Among 40 relapsed patients, the median time between initial diagnosis and relapse was 12.5 months (range 3-56 months). The sites of relapse were isolated BM (n = 9), primary local site with BM (9), primary local site (6), isolated CNS (4), local site with mediastinum (4), primary local site with other site (4), and others (4). Of all 48 patients, 3 were alive after chemotherapy alone. Of the 33 patients, 14 were alive after high dose chemotherapy (HDC)/SCT. With a 27.5-month median follow up period, the 3-year OS rate was 43.2 +/- 7.4% (estimate +/- SE). Univariate analysis identified two features (relapse within 12 months, T cell phenotype) as significant variables that predicted poor survival. Multivariate analysis showed novel statistically significant variables including relapse within 12 months from initial diagnosis (Hazard ratio 3.60) and absence of HDC/SCT (2.64).

Outcomes of patients with relapsed/primary refractory LBL were poor, but HDC/SCT for these patients was associated with good results.