Testis and epididymis
Other tumors not specific to testis
Granulocytic / myeloid sarcoma

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

Revised: 19 June 2017, last major update August 2013

Copyright: (c) 2003-2017, PathologyOutlines.com, Inc.

PubMed Search: Granulocytic sarcoma[title] or myeloid sarcoma[title] testis
Cite this page: Granulocytic sarcoma. PathologyOutlines.com website. http://pathologyoutlines.com/topic/testisgranulocyticsarcoma.html. Accessed October 20th, 2017.
Definition / general
  • Neoplasm composed of immature and mature granulocytes or monocytes that involves an extramedullary anatomic site
  • Includes leukemic involvement of testis
    • Common with ALL: 8% clinically, 20% microscopically; also AML
    • Bilateral involvement common
    • Testis may be first site of relapse
Terminology
  • Also called chloroma, myeloid sarcoma, monocytic sarcoma, extramedullary myeloid cell tumor, myelosarcoma, myeloblastoma
Epidemiology
  • Rare; case reports of ages 24 - 68 years
Pathophysiology
  • Usually history of myeloid neoplasm, most often acute myeloid leukemia, less often a myelodysplastic or myeloproliferative disease
  • Testicular involvement can be initial manifestation of AML that subsequently involves blood and bone marrow
  • Very rarely, testis is only site
  • Relatively more common with leukemias with prominent monocytic differentiation (acute myelomonocytic or acute monocytic leukemia, chronic myelomonocytic leukemia, Am J Clin Pathol 2005;124:445)
Clinical features
  • Testicular mass, testicular pain, constitutional symptoms (fever, general weakness, night sweats, weight loss)
Diagnosis
  • Based on histology and confirmed by immunohistochemical stains or flow cytometry
  • Clinical history can be very helpful
Laboratory
  • AFP and beta HCG within normal limits
Radiology description
Case reports
Treatment
  • Chemotherapy or radiation therapy, although bone marrow relapse is common
Gross description
  • Cream colored to yellowish tan, rubbery / firm testicular tumor with extensive paratesticular spread
Gross images

Images hosted on other servers:

Cream colored tumor

Microscopic (histologic) description
  • Normal testis architecture is effaced by primitive cells with scant cytoplasm; or cells with eosinophilic, occasionally granular cytoplasm
  • Prominent myelocytes with moderately abundant cytoplasm and round eccentric nuclei, resembling plasma cells
Microscopic (histologic) images

Images hosted on other servers:

Bone marrow: immature myeloid cells

Bone tumor: myeloblasts

Bone tumor: blast crisis

Myeloperoxidase

Cytology description
  • Cellular, discohesive cells with moderate cytoplasm, large oval to indented nuclei, distinct nuclear membranes
  • Also cells with scant cytoplasm, no eosinophilic granules, round / oval nuclei with prominent nucleoli (Ann Diagn Pathol 2000;4:17, Cancer 2000;90:364)
  • Variable numbers of eosinophilic myeloblasts, myelocytes and other maturing cells with eosinophilic granules - in some cases, myeloid differentiation is absent
  • Lymphoglandular bodies may be present in background
Cytology images

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Bone marrow - various images

Bone marrow

Negative stains
Differential diagnosis