Testis and epididymis
Germ cell tumors
Osteosarcoma

Author: Jennifer Gordetsky, M.D. (see Authors page)

Revised: 16 May 2017, last major update February 2014

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

PubMed Search: Osteosarcoma [title] testis

Cite this page: Osteosarcoma. PathologyOutlines.com website. http://pathologyoutlines.com/topic/testisosteosarcoma.html. Accessed May 25th, 2017.
Definition / general
  • A testicular tumor composed of pure osteoid forming malignant cells with no skeletal origin
Epidemiology
  • Pure testicular osteosarcoma is exceptionally rare
  • Case reports: mean 59 years, range 30 - 78 years
Pathophysiology
  • Usually derive from sarcomatous transformation of germ cell tumors (teratoma)
  • May also occur as a component of malignant mixed sex cord / stromal tumor
  • Pure osteosarcomas without teratomatous elements have also been reported; may arise from primitive testicular stromal cells or metaplastic stromal cells (Virchows Arch 2004;445:210, Int J Urol 2006;13:323)
Clinical features
  • Scrotal mass
Radiology description
  • Intratesticular heterogeneous solid mass with focal calcification
Prognostic factors
  • Organ confined disease is associated with a favorable prognosis
Case reports
Treatment
  • Orchiectomy
Clinical images

Images hosted on other servers:

Left testicular mass almost entirely calcified

Gross description
  • Well circumscribed, solid, firm, whitish tan, expansile mass compressing the surrounding testicular parenchyma
Gross images

Images hosted on other servers:

Off white colored tumor

Microscopic (histologic) description
  • Sheets of pleomorphic round to spindled cells with prominent nucleoli
  • Areas of neoplastic osteoid with scattered foci of mineralization
  • High mitotic activity and atypical mitoses
  • Osteoclasts can be seen among the area of osteoid formation
Microscopic (histologic) images

Images hosted on other servers:

Sarcomatous cell proliferation - H&E

Molecular / cytogenetics description
Differential diagnosis