A tumorous type of pulmonary rhabdomyomatous dysplasia

We report an extraordinary case of tumorous type of rhabdomyomatous dysplasia without any other malformation in a fetus of 23 weeks gestation. Histologically, autopsy showed distinctive striated muscle tissue in the upper and middle lobes of the right lung. Unusual in this case, compared with previously published reports, is the absence of further malformations, the occurrence in the apical parts of the lung and the marked degree of rhabdomyomatous dysplasia. The case report is followed by a differential diagnosis, review of the literature and discussion of the pathogenesis.