Pleuropulmonary Blastoma: More Than a Lung Neoplasm of Childhood.
Dehner Lp, Schultz Ka, Hill Da
Abstract
Pleuropulmonary blastoma (PPB), the most common primary malignant neoplasm of the lung in childhood, occurs in the same early age group (0-6 years) as the other more common solid tumors such as neuroblastoma and Wilms tumor. The tumor begins as a cystic lung lesion with the potential over a period of 3-5 years to progress to a high grade multipatterned primitive sarcoma in the absence of a malignant epithelial component. Several years after its initial description as a unique clinicopathologic entity, this and other tumors appeared to have a familial predilection which was later confirmed with the discovery of a heterozygous germline mutation in DICER1 whose protein is a member of ribonuclease III family of enzymes. It is estimated that 75%-80% of children with a PPB have the germline mutation. The other notable finding from our studies is the identification of a family of extrapulmonary neoplasms, including cystic nephroma and Sertoli-Leydig cell tumor of the ovary as two examples, also with DICER1 mutations.