Primary Cutaneous B‐Cell Lymphoblastic Lymphoma Arising from a Long‐Standing Lesion in a Child and Review of the Literature

Abstract Precursor B‐cell lymphoblastic lymphoma (B‐ LBL ) is a rare entity and primary cutaneous B‐ LBL is an even more uncommon diagnosis that typically affects children. A 4‐year‐old boy presented with a persistent rash on his left cheek for almost 2 years and was found to have primary cutaneous B‐ LBL . We report this case to emphasize that B‐ LBL should be in the differential diagnosis for an otherwise unimpressive persistent lesion in the head and neck region and review all reported pediatric cases of primary cutaneous B‐ LBL without extracutaneous involvement.