Wilms tumor Incidence Wilms tumor (nephroblastoma) is the most common primary renal tumor of childhood and the sixth most common childhood malignancy in the United States. Wilms tumor comprises approximately 6% of all childhood cancers and nearly 10% of all…
Neuroblastoma originates from primordial neural crest cells that normally give rise to adrenal medulla and sympathetic ganglia. Epidemiology Neuroblastoma is the most common extracranial solid tumor in children, accounting for 6% of all childhood malignancies. Neuroblastoma is the most common…
Tumors of the central nervous system (CNS) are frequently encountered tumors in children; approximately 35 cases per million in children under 15 years of age. Brain tumors are the second most common group of malignant tumors in childhood, accounting for…
Introduction Childhood non-Hodgkin lymphoma (NHL) is distinguished from adult NHL by differing frequencies of histopathologic types and by the greater frequency of extranodal presentations. With current combination chemotherapy regimens, survival is generally excellent (85 to over 90%) for all patients,…
Hodgkin lymphoma (HL) is characterized by progressive enlargement of lymph nodes. It is considered unicentric in origin and has a predictable pattern of spread by extension to contiguous nodes. Etiology and epidemiology 1. Specific etiology is unknown. 2. Overall there…
Acute myeloid leukemia (AML) is characterized by the abnormal proliferation and differentiation of myeloid precursors in the bone marrow. While the etiology of primary AML is unknown, certain predisposing factors can lead to secondary AML as discussed next. While AML…
Acute leukemias represent a clonal expansion and arrest at a specific stage of myeloid or lymphoid hematopoiesis. They constitute 97% of all childhood leukemias and consist of the following types: Acute lymphoblastic leukemia (ALL)—80%: of which 85% are B-cell acute…
Myelodysplastic syndromes Myelodysplastic syndromes (MDS) are clonal hematopoietic stem cell disorders characterized by varying degrees of cytopenias secondary to ineffective and dysplastic hematopoiesis and increased propensity to evolve into acute myeloid leukemia (AML). In contrast to adult MDS patients, who…
Lymphoproliferative disorders (LPDs) manifest with uncontrolled hyperplasia of lymphoid tissues (lymph nodes, spleen, bone marrow, liver). They are a heterogeneous group of diseases that range from reactive polyclonal hyperplasia (immunologic disorders) to true monoclonal (malignant) diseases. Angioimmunoblastic lymphadenopathy with dysproteinemia…
Introduction Langerhans cell histiocytosis and related neoplastic histiocytoses (Erdheim–Chester disease, juvenile xanthogranuloma, and Rosai–Dorfman disease) typically arise from clonal proliferation of myeloid precursor cells driven by pathologically activated MAPK signaling, where hemophagocytic lymphohistiocytosis is a heterogeneous syndrome characterized by excessive…