Testis and epididymis
Germ cell tumors
Choriocarcinoma

Author: Andres Matoso, M.D. (see Authors page)

Revised: 8 January 2018, last major update December 2017

Copyright: (c) 2002-2018, PathologyOutlines.com, Inc.

PubMed Search: Choriocarcinoma[TI] testis

Cite this page: Matoso, A. Choriocarcinoma. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/testischorio.html. Accessed December 11th, 2018.
Definition / general
  • Malignant germ cell tumor composed of syncytiotrophoblast, cytotrophoblast and intermediate trophoblast cells
  • Identical tumors arise in placenta, ovary, mediastinum and abdomen (from sequestered cell rests)
Essential features
  • Hemorrhagic mass
  • Early metastases
  • Three cell types: syncytiotrophoblast, cytotrophoblast, intermediate trophoblast
Epidemiology
  • Young men, 25 - 35 years old
Sites
  • Testis, retroperitoneum, mediastinum
Pathophysiology
  • Unknown
Etiology
  • Unknown
Clinical features
  • 0.3 - 1% of germ cell tumors are pure choriocarcinoma but mixed tumors are more common (8%)
  • May present initially with metastases (liver, lung, mediastinum, retroperitoneum) with normal testis or small tumor but with increased serum hCG
  • Early hematogenous spread to lungs, liver and brain
  • Poor prognosis if pure
  • May present with gynecomastia or hyperthyroidism
Diagnosis
  • Histopathology
Laboratory
  • High hCG levels (greater than 100,000 mIU/ml)
Prognostic factors
  • Poor prognosis if pure and presents in advanced stage
Case reports
Treatment
  • Surgery and chemotherapy
Gross description
  • Hemorrhagic tumor or scar
Gross images

Images hosted on PathOut server:

Images contributed by Dr. Andres Matoso:

Large hemorrhagic tumor

Microscopic (histologic) description
  • Tumor is composed of varying amounts of:
    • Syncytiotrophoblast cells: large multinucleated cells with large irregular nuclei
    • Cytotrophoblast cells: pale cytoplasm with single large nucleus and prominent nucleolus
    • Intermediate trophoblast cells: clear cytoplasm, larger than cytotrophoblasts with single nuclei
    • Adjacent testicular parenchyma with intratubular germ cell neoplasia in situ
Microscopic (histologic) images

Images hosted on PathOut server:

Images contributed by Dr. Andres Matoso:

Cytotrophoblasts and syncytio-trophoblasts

In a vessel of the albuginea



Images hosted on other servers:

Cytotrophoblasts and syncytio-trophoblasts

Cytotrophoblastic cells

Syncytio-trophoblastic cells

Abundant syncytio-trophoblasts

Syncytio-trophoblasts

hCG+

Positive stains
Negative stains
Molecular / cytogenetics description
  • Isochrome 12p
Differential diagnosis
Board review question #1
Which biomarker is most frequently elevated in choriocarcinoma?

  1. hCG in the hundreds level
  2. hCG in the thousands level
  3. hGH
  4. T4
Board review answer #1
B. hCG in the thousands level
Board review question #2
Which of the following germ cell tumor markers is positive in choriocarcinoma?

  1. CD30
  2. CD117
  3. OCT3 / 4
  4. SALL4
Board review answer #2
D. SALL4
Board review question #3
Which of the following markers helps to differentiate choriocarcinoma from embryonal carcinoma?

  1. CD117
  2. Cytokeratin
  3. EMA
  4. OCT4
Board review answer #3
D. OCT4