title: Intraplacental smooth muscle tumor: a case report.
abstract: We present the second reported case of a smooth muscle neoplasm involving the placental parenchyma. On gross examination, the tumor easily separated from the uterus and had a whorled cut surface with finger-like extensions into the villous parenchyma, very similar to the previously described case. The differential diagnosis included a primary smooth muscle tumor of the placenta (placental leiomyoma), a primary uterine neoplasm incorporated into the placenta, and a metastatic sarcoma. In this case, the infant was male, and the polymerase chain reaction technique demonstrated the presence of Y chromosome gene in the placental parenchyma and its absence in the placental neoplasm. Thus, this neoplasm, despite its gross appearance of a primary placental tumor, actually represented an incorporated benign uterine leiomyoma.
authors.affiliation: Department of Anatomic Pathology, Yale University School of Medicine, New Haven, Connecticut, USA.
authors.forename: L M
authors.initials: LM
authors.lastname: Ernst
authors.forename: P
authors.initials: P
authors.lastname: Hui
authors.forename: V
authors.initials: V
authors.lastname: Parkash
mesh_terms: D000328:Adult; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007889:Leiomyoma / Q000473:pathology*; D008297:Male; D009130:Muscle, Smooth / Q000473:pathology; D010922:Placenta Diseases / Q000473:pathology*; D016133:Polymerase Chain Reaction; D011247:Pregnancy; D011252:Pregnancy Complications, Neoplastic / Q000473:pathology*; D012509:Sarcoma / Q000473:pathology*; D014594:Uterine Neoplasms / Q000473:pathology*; D014998:Y Chromosome