Testis and epididymis
Germ cell tumors

Author: Turki Al-Hussain, M.D. (see Authors page)

Revised: 16 May 2017, last major update January 2013

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PubMed Search: PNET testis

Cite this page: PNET. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/testispnet.html. Accessed February 23rd, 2018.
Definition / general
  • Primitive NEuroectodermal Tumor / Ewing sarcoma
  • Frequent "nongerm cell" tumor in patients with testicular germ cell tumors (Mod Pathol 2010;23:972)
  • Composed entirely of immature neural tissue
  • Considered a monodermal teratoma
  • Often fatal if metastases present (extratesticular), longer survival if neuroblastoma-like metastases
  • May arise in germ cell tumors and be testicular, extratesticular or both (Am J Surg Pathol 1997;21:896)
Case reports
Gross description
  • Grayish white, necrotic
Microscopic (histologic) description
  • Small cells with minimal cytoplasm in sheets, tubules, rosettes, pseudorosettes, medullary tubules and focally forming glia; overt overgrowth over immature teratoma by these cells
Microscopic (histologic) images

Images hosted on other servers:

Various Images

Positive stains
Electron microscopy description
  • Neurosecretory granules