B Lymphoblastic Leukemia/Lymphoma with Intrachromosomal Amplification of Chromosome 21

**Semantic type:** Neoplastic Process

**Definition:** B lymphoblastic leukemia/lymphoma characterized by amplification of a portion of chromosome 21. It usually occurs in children and is associated with an adverse prognosis.

**Synonyms:** - B Lymphoblastic Leukemia/Lymphoma with iAMP21 - B-Lymphoblastic Leukemia/Lymphoma with Intrachromosomal Amplification of Chromosome 21 - B-Lymphoblastic Leukemia/Lymphoma with iAMP21