22-year-old woman with gestational diabetes    

Findings and diagnosis

Microscopic findings

A microscopic exam of the placenta shows a circumscribed mass composed of small vascular structures. The vessels are predominantly capillaries. There is a compact, sheetlike arrangement of capillaries in some regions, while others show edema between the capillaries. The vascular endothelium itself is flat, and there is no cytologic atypia. These microscopic features are consistent with a chorangioma.

Differential diagnosis

  • Chorangiosis
  • Teratoma
  • Infantile hemangioma
  • Diffuse multifocal chorangiomatosis
  • Localized chorangiomatosis
  • Chorangioma

Diagnosis: Chorangioma