Mediastinum
Cystic lesions
Teratoma - cystic

Author: Hanni Gulwani, M.D. (see Authors page)

Revised: 15 June 2018, last major update December 2012

Copyright: (c) 2003-2018, PathologyOutlines.com, Inc.

PubMed Search: Teratoma cystic mediastinum

Cite this page: Gulwani, H. Teratoma - cystic. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/mediastinumteratoma.html. Accessed August 16th, 2018.
Definition / general
  • Common; 10 - 20% of mediastinal lesions
  • In anterosuperior mediastinum
  • Neoplastic, not a developmental malformation
  • Usually contain tissue derived from at least 2 of 3 germ cell layers - endoderm, mesoderm, ectoderm
  • 50% have cough, dyspnea or chest pain
  • Tumors adhering to lung, pericardium or blood vessels are either malignant or ruptured mature teratomas with inflammatory reaction
Epidemiology
  • Usually children or young adults (mean age 20 years)
Clinical features
  • May be associated with Klinefelter syndrome (XXY)
  • Rarely associated with acute myelogenous leukemia
Case reports
Gross description
  • Cystic with variable solid component
  • Malignant tumors are often adherent to adjacent structures or have necrosis
  • Benign tumors often have keratinous debris, cartilage or mucus
Microscopic (histologic) description
  • Mature squamous epithelium with cutaneous appendages (commonly), GI columnar epithelium, neuroglia, bone, cartilage, fat, striated muscle
  • Also choroid plexus, hepatocytes, pancreas, retinal type tissue
  • May contain immature neuroepithelial tissue (see Immature teratoma below)
  • No cholesterol granulomas
Microscopic (histologic) images

Images hosted on other servers:

Mature cystic teratoma

Respiratory epithelium

Bone, cartilage and mucinous glands

Mature cystic teratoma

Mature teratoma

Immature teratoma
Definition / general
  • Contains immature neuroepithelial tissue such as embryonic tubules
  • Benign behavior in patents under age 15
Mature teratoma with malignant transformation
Definition / general
  • Very rare
  • Contain overtly malignant tissue
  • Tumors with germ cell components are classified as malignant mixed germ cell tumors

Case reports