Terms in bone, joint and soft-tissue tumors

This page is designed to provide the definition of commonly used terms in musculoskeletal oncology.

Musculoskeletal oncology is virtually synonymous with orthopedic oncology. It is a field of medicine that deals with all aspects of tumors, benign and malignant, primary, metastatic and palliative of the bones, joints and soft tissues (ie. fat, muscle, fascia, bone, ligaments, tendons, nerves etc).

Oncology is a field of medicine dealing with tumors (benign and malignant).

Cancers are conditions where there is deregulated growth of cells in the body. They are characterized by local spread and metastasis. When these cancers involve the body liners (ie. skin, the lining of glands, respiratory tract, gastrointestinal tract), they are called carcinomas. If they involve the bones, joints and soft tissues they are called sarcomas. Specifically cancers of the blood end with -aemia (leukemia, polycythemia).

Benign tumors are named after the tissue they look like (less accurately described as 'tissue of origin'). Hence a tumor of fat ( latin 'lipo') would be a lipoma if it is benign or liposarcoma if malignant. Similarly, examples are to be had in bone (osteoma, osteosarcoma), cartilage (chondroma, chondrosarcoma), ligaments and tendons (fibroma, fibrosarcoma), muscle (rhabdomyoma, rhabdomyosarcoma). As a rule these tumors do not metastasize. Nevertheless, in musculoskeletal oncology these tumors can grow very large and turn malignant. Also oddly, some of these benign tumors like giant cell tumors can metastasize.

In musculoskeletal oncology there are in addition numerous other tumors named after components of the bone marrow like giant cells (giant cell tumor, giant cell rich sarcoma) also known as osteoclasts (osteoclastoma). And then there are the tumors that bear their founder's names Ewing's sarcoma (after James Ewing). These are specifically dealt with elsewhere on this website.

Figure. The type of surgeries in musculoskeletal oncology are divided into amputations or resections. Amputations obviously involve a loss of a limb and resections facilitate the limb salvage procedures. Intralesional excisions occur within the tumor margins, marginal at the margin, wide with a cuff of normal tissue (beyond the reactive zone) and radical involves loss of the compartment.