Placenta
Nontrophoblastic neoplasms
Chorangiomatosis

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

Revised: 30 October 2017, last major update October 2017

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

PubMed Search: Chorangiomatosis

Cite this page: Garg,S. Chorangiomatosis. PathologyOutlines.com website. http://pathologyoutlines.com/topic/placentachorangiomatosis.html. Accessed November 20th, 2017.
Definition / general
  • Nonexpansile vascular proliferation similar to chorangioma but occurring in otherwise normal stem villi
  • Associated with preeclampia, multiple gestation, premature delivery at 26 to 32 weeks (Hum Pathol 2000;31:945)
  • Diffuse multifocal subtype asssociated with extreme prematurity (< 32 weeks), congenital malformations, intrauterine growth restriction, delayed villous maturation, avascular villi and placentomegaly (Pediatr Dev Pathol 2011;14:38)
Essential features
  • Villous capillary lesion occurring due to reactive hyperplasia to hypoxia (similar to the other villous capillary lesions of placenta, J Pregnancy 2014;2014:193925)
  • Overall prevalence is 0.55% (less common than chorangiosis)
  • Heterogeneous and less well defined lesion with features intermediate between chorangioma and chorangiosis
  • Diffuse multifocal chorangiomatosis is morphologically similar to chorangioma and localized chorangiomatosis but has a distinct clinicopathologic profile (may occur in < 32 weeks gestation)
Pathophysiology
  • Capillary hyperplasia occurs as a reaction to tissue hypoxia that stimulates neoangiogenesis by activating growth factors such as VEGF and PDGF.
Etiology
  • Chorangioma and localized chorangiomatosis are etiologically similar hyperplastic lesions arising in subtrophoblastic reticular connective tissue of stem villi
  • More prevalent in maternal preeclampsia, multiple gestation and prematurity
  • No definite association with maternal diabetes mellitus (unlike chorangiosis)
Clinical features
  • Chorangioma and chorangiomatosis often coexist
  • Higher rate of association with preeclampsia
Case reports
Microscopic (histologic) description
  • Proliferation of small capillaries surrounded by a circumferential layer of pericytes and loose reticulin fibers that merge into surrounding villous stroma
  • Occurs within the stem villi (contain a dense vimentin positive collagenized core) and does not form a discrete mass
  • Focal subtype involves < 5 contiguous villi
  • Segmental subtype involves > 5 contiguous villi
  • Diffuse / multifocal subtype involves several noncontiguous areas of the placenta
  • Occasional cases of diffuse multifocal chorangiomatosis can show peripheral areas of smaller capillaries more typical of chorangiosis
Microscopic (histologic) images

Images hosted on other servers:

Various images

Positive stains
Differential diagnosis
  • Chorangioma: well circumscribed nodular lesion showing capillary hyperplasia surrounded by trophoblastic cells
  • Chorangiosis: individual capillaries are surrounded by distinct basement membranes and there is no circumferential lining of pericytes or loose reticulin bundles
Additional references
Board review question #1
Which of the following statements is true?

  1. Chorangiomatosis arises in the terminal villi of the placenta.
  2. Chorangiosis is 10 times more prevalent than chorangioma or chorangiomatosis.
  3. Chorangiomatosis lesion is always negative for muscle specific actin stain.
  4. All of the above.

Board review answer #1
B. Chorangiosis is 10 times more prevalent than chorangioma or chorangiomatosis.