Placenta
Nontrophoblastic neoplasms
Chorangioma

Author: Shipra Garg, M.D. (see Authors page)

Revised: 19 October 2017, last major update July 2017

Copyright: (c) 2002-2017, PathologyOutlines.com, Inc.

PubMed Search: Chorangioma [title] placenta

Cite this page: Garg, S. Chorangioma. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/placentachorangioma.html. Accessed October 23rd, 2017.
Definition / general
  • Most common tumor of the placenta (incidence 1%) (Rare Tumors 2010;2:e67)
  • Hamartoma-like or hyperplastic capillary lesion rather than a true neoplasm
  • If size > 4 - 5 cm, associated with significant effects on the fetal hemodynamic and circulatory processes leading to clinical complications (J Clin Diagn Res 2016;10:ED03)
  • These tumors have no malignant potential
Essential features
  • Arise from major stem villi under the chorionic plate or at the placental margin
  • Angiomatous (capillary) are the most frequent histologic type
  • Chorangiomas must be differentiated from other villous capillary lesions, namely chorangiomatosis and chorangiosis
  • Atypical chorangioma: rare, characterized by increased cellularity and mitotic activity, necrosis and solid areas, may resemble sarcoma but benign behavior (Int J Surg Pathol 2015;23:364)
Risk factors
  • More common in high altitudes (hypoxia related), increased maternal age, diabetes, hypertension, multiple pregnancy
Clinical features
  • Most are small in size, clinically unimportant and sometimes regress
  • Large (> 4 - 5 cm) and multiple chorangiomas associated with dismal prognosis due to high association with maternal and fetal complications (30 - 50%) (Case Rep Obstet Gynecol 2012;2012:913878)
  • Complications include (Indian Pediatr 1996;33:520):
    • Polyhydramnios
    • Toxemia
    • Preterm labor
    • Fetal congestive cardiac failure (due to arteriovenous shunt)
    • Hydrops
    • IUGR
    • Fetal hemolytic anemia / thrombocytopenia
Radiology description
  • Obstetric ultrasound images may show hypoechoic circumscribed intraplacental mass containing small anechoic spaces
Case reports
Treatment
  • In situations where maternal and fetal complications exist, possible interventions include (Fetal Pediatr Pathol 2010;29:199):
    • Serial fetal transfusions (Ginekol Pol 2011;82:304)
    • Fetoscopic laser coagulation of vessels
    • Chemosclerosis with absolute alcohol
    • Endoscopic surgical devascularization
  • Interventions however, all carry dismal prognosis
Gross description
  • Solitary or multiple nodules mostly located on the chorionic plate and or placental margin
  • Mostly fleshy, congested, red / tan cut surface resembling a blood clot, when perfused
  • May appear as a firm white lesion when infarcted
Gross images

Images hosted on other servers:

Chorangioma

Tumor close up

Cut surface with almost 5 cm chorangioma

Microscopic (histologic) description
  • Well circumscribed mass arising from stem villi and resembling capillary hemangioma
  • Proliferation of capillary sized vessels causing expansion of contiguous affected villi
  • Composed of a mixture of endothelial cells, pericytes and myofibroblastic stromal cells
  • There may be associated nonspecific surface trophoblastic proliferation (up to 40% cases), which is benign
  • Occasionally associated with degenerative changes like hyalinization, necrosis and calcification
Microscopic (histologic) images

Images hosted on other servers:

Chorangioma intermediate power view

Chorangioma higher power view

Cavernous vessels present in some cases

Evenly spaced vessels in fibroblastic matrix

Positive stains
Negative stains
Electron microscopy description
  • Normal endothelial cells and various vascular structures
Differential diagnosis
Board review question #1
Which of the following is not associated with atypical chorangioma?

  1. Immunohistochemical staining for factor VIII antigen.
  2. Increased cellularity and high mitotic activity.
  3. Invasion, metastasis and biological aggressiveness.
  4. Large tumor size.
  5. Tumor necrosis.
Board review answer #1
C. Atypical chorangioma may be associated with increased cellularity, high mitotic activity, tumor necrosis, positive staining with factor VIII antigen and may have large tumor size. It however, lacks metastasis, invasion or biological aggressiveness.