Topoisomerase II alpha (TOP2A)

Author: Semir Vranić, M.D., Ph.D. (see Authors page)

Revised: 10 August 2018, last major update June 2010

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

PubMed Search: Topoisomerase II alpha[TI] OR TOP2A[TI] free full text[sb]

Page views in 2018: 227
Page views in 2019 to date: 31
Cite this page: Vranić, S. Topoisomerase II alpha (TOP2A). website. Accessed January 22nd, 2019.
Definition / general
  • The best tool and cutoff values for TOP2A assessment are unknown
  • The most commonly used method is TOP2A gene analysis by FISH (Pathol Res Pract 2010;206:156)
  • TOP2A protein expression by immunohistochemistry is also commonly used
Uses by pathologists
Microscopic (histologic) images

Images hosted on other servers:
Missing Image

Breast carcinoma, c/o Semir Vranić, M.D., Ph.D.

Missing Image

Breast carcinomas

Missing Image

Hodgkin lymphoma

Missing Image Missing Image

Lung cancer: small cell (+) versus adenocarcinoma (focal +)

Missing Image


Missing Image

Pancreatic endocrine neoplasm

Missing Image

Prostate, hormone insensitive

Missing Image

Prostate, various

Missing Image


Positive staining - normal
  • Tissues with proliferating cells, especially spermatocytes, germinal centers and proliferative endometrium (Mod Pathol 1997;10:168)
Positive staining - not malignant
Positive staining - malignant
Negative staining
  • Terminally differentiated tissues (because TOP2A is not expressed in G0 phase): cerebral cortex, skeletal muscle and nerve
  • Rare positive cells in breast, salivary gland and kidney (Mod Pathol 1997;10:168)
Molecular / cytogenetics images

Images hosted on other servers:

no gene amplification,
c/o Semir Vranić, M.D., Ph.D.

Breast carcinoma: FISH of HER2 and TOP2A