Testis & epididymis
Germ cell tumors
Choriocarcinoma
Author: Andres Matoso, M.D.
Topic Completed: 1 December 2017
Minor changes: 9 September 2020
Copyright: 2002-2020, PathologyOutlines.com, Inc.
PubMed Search: Choriocarcinoma[TI] testis
Table of Contents
Definition / general | Essential features | Epidemiology | Sites | Pathophysiology | Etiology | Clinical features | Diagnosis | Laboratory | Prognostic factors | Case reports | Treatment | Gross description | Gross images | Microscopic (histologic) description | Microscopic (histologic) images | Positive stains | Negative stains | Molecular / cytogenetics description | Differential diagnosis | Additional references | Board review style question #1 | Board review answer #1 | Board review style question #2 | Board review answer #2 | Board review style question #3 | Board review answer #3Cite this page: Matoso A. Choriocarcinoma. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/testischorio.html. Accessed September 19th, 2020.
Definition / general
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
- 20 year old man with pure testicular choriocarcinoma with pulmonary metastases (Case Rep Oncol Med 2015;2015:345018)
Treatment
- Surgery and chemotherapy
Gross description
- Hemorrhagic tumor or scar
Gross images
Contributed by Andres Matoso, M.D.
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
Contributed by Andres Matoso, M.D.
Cytotrophoblasts and syncytio-trophoblasts
In a vessel of the albuginea
Images hosted on other servers:
hCG+
Positive stains
- hCG, PLAP, GATA3, EMA, cytokeratin 7, SALL4, glypican 3
Molecular / cytogenetics description
- Isochrome 12p
Differential diagnosis
- Embryonal carcinoma
- Nonchoricarcinoma trophoblastic tumors
- Seminoma with syncytiotrophoblastic cells: these are usually found in clusters around blood vessels; may cause elevation of hCG in the hundreds of IU/ml
- Trophoblastic differentiation in carcinomas: i.e. urothelial carcinoma (very rare)
Additional references
Board review style question #1
Which biomarker is most frequently elevated in choriocarcinoma?
- hCG in the hundreds level
- hCG in the thousands level
- hGH
- T4
Board review answer #1
B. hCG in the thousands level
Board review style question #2
Which of the following germ cell tumor markers is positive in choriocarcinoma?
- CD30
- CD117
- OCT3 / 4
- SALL4
Board review answer #2
D. SALL4
Board review style question #3
Which of the following markers helps to differentiate choriocarcinoma from embryonal carcinoma?
- CD117
- Cytokeratin
- EMA
- OCT4
Board review answer #3
D. OCT4
