Therapeutic targets in childhood B‐acute lymphoblastic leukemia: what about HER2/neu?

Abstract

Acute lymphoblastic leukemia (ALL), the most common cancer in childhood, 1 has nowadays a 5-year overall survival (OS) exceeding 90%. 2 Unfortunately, relapse occurs in about 20% of the cases and even after a second cytological remission (CR), 5-year OS does not exceed 30%-40%. 3 Some antigens expressed by malignant leukemic cells can serve as therapeutic targets in refractory ALL for unconjugated monoclonal antibodies (MoAbs), alone or associated to chemotherapy, MoAbs conjugated to toxins or radionuclides or bispecific antibodies engaging T-cells. 4 Here, we evaluated the expression level of CD19, CD20, CD38, CD22, and HER2/neu on childhood B-ALL blasts, as potential therapeutic targets in case of treatment failure or relapse.Between January 2011 and February 2020, 125 young patients were diagnosed with B-ALL (n ¼ 115) or relapsed (n ¼ 10) in Nantes University Hospital. Their median age was 5.5 years old (range 1 year 3 months-24 years 9 months). There were 102 children (median age 4 years 9 months) and 23 adolescent-young adults (AYA; median age 19 years 5 months). Patients, or their parents, signed a written

The two‐hit hypothesis in practice: Monozygotic twins with simultaneous hyperdiploid acute lymphoblastic leukemia

“…While typically associated with breast cancer, HER2 expression has been found in approximately 13% of pediatric B-ALL. 12 Twin B additionally had a somatic PTPN11 E76Q mutation, which is a regulator of the RAS pathway and is a known lesion in pediatric B-ALL. 13 The germline CD36 and CDH1 mutations are of unclear significance.…”