Can CD34(+)CD38(−) lymphoblasts, as likely leukemia stem cells, be a prognostic factor in B-cell precursor acute lymphoblastic leukemia in children?

BACKGROUND: CD34(+)CD38(−) lymphoblasts as likely leukemia stem cells (LSCs) may be responsible for a worse response to treatment and may be a risk factor for recurrence in B-cell precursor acute lymphoblastic leukemia (BCP-ALL). OBJECTIVE: The study objective was to assess the prognostic role of CD34(+)CD38(−) lymphoblasts in bone marrow on the day of BCP-ALL diagnosis. METHODS: 115 patients with BCP-ALL, the median age of 4.5 years (range 1.5–17.9 years), gender: female 63 (54.8%) with BCP-ALL were enrolled; Group I (n = 90)—patients with CD34(+)CD38(+) antigens and Group II (n = 20)—patients with CD34(+)CD38(−) antigens on the lymphoblast surface. RESULTS: A worse response on Days 8, 15, and 33 of therapy and at the end of treatment in Group II (CD34(+)CD38(−)) was more often observed but these differences were not statistically significant. A significantly higher incidence of BCP-ALL recurrence was in Group II. CONCLUSIONS: 1. In BCP-ALL in children, the presence of CD34(+)CD38(−) lymphoblasts at the diagnosis does not affect the first remission. 2. In BCP-ALL in children, the presence of CD34(+)CD38(−) lymphoblasts at the diagnosis may be considered an unfavorable prognostic factor for disease recurrence. 3. It is necessary to further search for prognostic factors in BCP-ALL in children.