Find Information About:

Drugs & Supplements

Get information and reviews on prescription drugs, over-the-counter medications, vitamins, and supplements. Search by name or medical condition.

Pill Identifier

Pill Identifier

Having trouble identifying your pills?

Enter the shape, color, or imprint of your prescription or OTC drug. Our pill identification tool will display pictures that you can compare to your pill.

Get Started

My Medicine

Save your medicine, check interactions, sign up for FDA alerts, create family profiles and more.

Get Started

WebMD Health Experts and Community

Talk to health experts and other people like you in WebMD's Communities. It's a safe forum where you can create or participate in support groups and discussions about health topics that interest you.

  • Second Opinion

    Second Opinion

    Read expert perspectives on popular health topics.

  • Community


    Connect with people like you, and get expert guidance on living a healthy life.

Got a health question? Get answers provided by leading organizations, doctors, and experts.

Get Answers

Sign up to receive WebMD's award-winning content delivered to your inbox.

Sign Up

Cancer Health Center

Font Size

Adult Soft Tissue Sarcoma Treatment (PDQ®): Treatment - Health Professional Information [NCI] - Cellular Classification of Adult Soft Tissue Sarcoma

Soft tissue sarcomas are classified histologically according to the soft tissue cell of origin. Additional studies, including electron microscopy, specialized immunohistochemistry, flow cytometry, cytogenetics, and tissue culture studies may allow identification of particular subtypes within the major histologic categories. For example, S100 antigen suggests neural sheath origin, cytokeratin suggests epithelioid or synovial cell origin, and factor VIII-related antigen suggests endothelial origin. Likewise, some subtypes of sarcomas have characteristic genetic markers, but these markers are not generally used in the routine clinical setting (e.g., t(X;18)(p11;q11) in synovial sarcomas and t(12;16)(q13;p11) in myxoid and round-cell sarcomas).[1,2,3]

The histologic grade reflects the metastatic potential of these tumors more accurately than the classic cellular classification listed below. Pathologists assign a grade based on the number of mitoses per high-powered field, the presence of necrosis, cellular and nuclear morphology, and the degree of cellularity; discordance among expert pathologists regarding tumor grade, and even histologic subtype, can be substantial.[4]

Recommended Related to Cancer

What is prevention?

Cancer prevention is action taken to lower the chance of getting cancer. By preventing cancer, the number of new cases of cancer in a group or population is lowered. Hopefully, this will lower the number of deaths caused by cancer. To prevent new cancers from starting, scientists look at risk factors and protective factors. Anything that increases your chance of developing cancer is called a cancer risk factor; anything that decreases your chance of developing cancer is called a cancer protective...

Read the What is prevention? article > >

The World Health Organization lists the following cell types in its classification of soft tissue sarcomas:[5,6]

  • Adipocytic tumors.
    • Dedifferentiated liposarcoma.*
    • Myxoid/round cell liposarcoma.
    • Pleomorphic liposarcoma.
  • Fibroblastic/myofibroblastic tumors.
    • Fibrosarcoma.**
    • Myxofibrosarcoma, low grade.
    • Low-grade fibromyxoid sarcoma.
    • Sclerosing epithelioid fibrosarcoma.
  • So-called fibrohistiocytic tumors.
    • Undifferentiated pleomorphic sarcoma/malignant fibrous histiocytoma (MFH) (including pleomorphic, giant cell, myxoid/high-grade myxofibrosarcoma, and inflammatory forms).
  • Smooth muscle tumors.
    • Leiomyosarcoma.
  • Skeletal muscle tumors.
    • Rhabdomyosarcoma (embryonal, alveolar, and pleomorphic forms).
  • Vascular tumors.
    • Epithelioid hemangioendothelioma.
    • Angiosarcoma, deep.***
  • Tumors of peripheral nerves.
    • Malignant peripheral nerve sheath tumor.
  • Chondro-osseous tumors.
    • Extraskeletal chondrosarcoma (mesenchymal and other variants).
    • Extraskeletal osteosarcoma.
  • Tumors of uncertain differentiation.
    • Synovial sarcoma.
    • Epithelioid sarcoma.
    • Alveolar soft part sarcoma.
    • Clear cell sarcoma of soft tissue.
    • Extraskeletal myxoid chondrosarcoma.
    • Primitive neuroectodermal tumor (PNET)/extraskeletal Ewing tumor.
    • Desmoplastic small round cell tumor.
    • Extrarenal rhabdoid tumor.
    • Undifferentiated sarcoma; sarcoma, not otherwise specified (NOS).

*It is recognized that dedifferentiated liposarcoma primarily arises in the context of deep atypical lipomatous tumor/well-differentiated liposarcoma, a sarcoma of intermediate malignancy because of the lack of metastatic capacity. **The category of fibrosarcoma can be inclusive of fibrosarcomatous differentiation in dermatofibrosarcoma protuberans. ***Cutaneous angiosarcoma may be difficult to stage using the AJCC system. (Refer to the PDQ summary on Gastrointestinal stromal tumor [GIST] summary for more information.


  1. Singer S, Nielsen T, Antonescu CR: Molecular biology of soft tissue sarcoma. In: DeVita VT Jr, Lawrence TS, Rosenberg SA: Cancer: Principles and Practice of Oncology. 9th ed. Philadelphia, Pa: Lippincott Williams & Wilkins, 2011, pp 1522-32.
  2. Singer S, Maki RG, O'Sullivan B: Soft tissue sarcoma. In: DeVita VT Jr, Lawrence TS, Rosenberg SA: Cancer: Principles and Practice of Oncology. 9th ed. Philadelphia, Pa: Lippincott Williams & Wilkins, 2011, pp 1533-77.
  3. Malawer MM, Helman LJ, O'Sullivan B: Sarcomas of bone. In: DeVita VT Jr, Lawrence TS, Rosenberg SA: Cancer: Principles and Practice of Oncology. 9th ed. Philadelphia, Pa: Lippincott Williams & Wilkins, 2011, pp 1578-1609.
  4. Alvegård TA, Berg NO: Histopathology peer review of high-grade soft tissue sarcoma: the Scandinavian Sarcoma Group experience. J Clin Oncol 7 (12): 1845-51, 1989.
  5. Soft tissue sarcoma. In: Edge SB, Byrd DR, Compton CC, et al., eds.: AJCC Cancer Staging Manual. 7th ed. New York, NY: Springer, 2010, pp 291-6.
  6. Brodowicz T, Schwameis E, Widder J, et al.: Intensified Adjuvant IFADIC Chemotherapy for Adult Soft Tissue Sarcoma: A Prospective Randomized Feasibility Trial. Sarcoma 4 (4): 151-60, 2000.

    This information is produced and provided by the National Cancer Institute (NCI). The information in this topic may have changed since it was written. For the most current information, contact the National Cancer Institute via the Internet web site at http:// cancer .gov or call 1-800-4-CANCER.

    WebMD Public Information from the National Cancer Institute

    Last Updated: 8/, 015
    This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.
    Next Article:

    Today on WebMD

    Colorectal cancer cells
    New! I AM Not Cancer Facebook Group
    Lung cancer xray
    See it in pictures, plus read the facts.
    sauteed cherry tomatoes
    Fight cancer one plate at a time.
    Ovarian cancer illustration
    Real Cancer Perspectives
    Jennifer Goodman Linn self-portrait
    what is your cancer risk
    colorectal cancer treatment advances
    breast cancer overview slideshow
    prostate cancer overview
    lung cancer overview slideshow
    ovarian cancer overview slideshow
    Actor Michael Douglas