A

Gingival hypertrophy is most typical of acute myeloid leukemia—especially the monocytic subtypes—and is uncommon in the majority of childhood acute leukemias, which are acute lymphoblastic leukemia (≈80%) [Chan, 2002, PMID 11951089; Ravikumar, 2016, PMID 27433057]. In contrast, mucosal pallor from anemia and purpura from thrombocytopenia are frequent presenting signs, and the pediatric disease is indeed usually of the lymphoblastic variety [Clarke, 2016, PMID 27647842; Chan, 2002, PMID 11951089].