Bone cancer (sarcoma)

Introduction

Sarcomas are rare cancers that develop in the supporting or connective tissues of the body such as muscle, bone, nerves, cartilage, blood vessels and fat.

There are around 320 new cases of sarcoma diagnosed each year in Scotland.

Sarcomas account for about 11% of childhood cancers and about 14% of cancers in teenagers.

Most sarcomas (about 55%) affect the limbs, most frequently the leg. About 15% affect the head and neck area or are found externally on the trunk, while the remainder will be found internally in the retroperitoneum (abdominal area).

Types of sarcoma

Sarcomas fall into three broad categories:

There are around 70 different sub-types of sarcoma within these broad categories. These sub-types are determined by the tissue of origin (the tissue in the body where the tumour originally formed), genetic characteristics or by other molecular analysis undertaken by expert pathologists.

How does cancer begin?

Bone sarcomas occur when the cells in the bones grow more quickly than normal. This produces a lump of tissue known as a tumour.

About bone sarcoma

Bone sarcomas affect less than 50 people in Scotland each year, making it a very rare form of cancer.

Most bone sarcomas in younger people affect the leg while in adults they will occur in more varied sites around the body.

Not all bone cancers are sarcomas. If a cancer has spread from another primary location (e.g. breast or prostate cancer) to the bone, this is a different type of cancer known as secondary disease (metastasis). All primary bone cancers originating in the bone are sarcomas.

There are five main types of bone sarcoma:

  • Osteosarcoma
  • Chondrosarcoma
  • Ewing's sarcoma
  • Chordoma
  • Giant cell tumour (GCT)

Sarcoma services in Scotland

All patients with sarcomas in Scotland are managed by health professionals who are members of the Scottish Sarcoma Network (SSN) .

The Scottish Sarcoma Network is one of the three national managed clinical networks for some of the rarer cancers in Scotland.  It was officially launched in November 2004 during its first AGM.  Its primary aim is to ensure equity of care for all patients in Scotland with sarcoma.  The aim will be achieved by prospectively auditing the quality of care provided to all patients in Scotland so that continual improvements can be made.  This will hopefully lead to the outcomes and quality of life for patients being improved.

The skeleton

To understand bone sarcoma it can be helpful to know more about the skeleton. There are more than 200 bones in the human body. The function of the bones is to:

  • support the body
  • protect parts of the body
  • act as levers and allow us to move.

The following diagram shows the skeleton.

This diagram has been taken from Cancer Research UK's information about the bones.

Diagram showing the skeleton

The long bones of the arms and legs are supporting bones. The bones of the rib cage protect the organs of the chest. The skull bones protect the brain.

The end of every long bone in the body is covered in a smooth, shiny tissue called cartilage. Fibrous straps called tendons hold the long bones together. The tendons and cartilage make joints that allow the bones to move smoothly against each other.

The bone cells

Bone consists of a framework of supporting material called connective tissue. This framework gives the bone its strength. Throughout this framework are the bone cells.

Bone contains minerals such as calcium.

There are three main types of cells in our bones:

  • Osteoblasts – these build up the bone framework.
  • Osteoclasts – these break down bone.
  • Osteocytes – these are osteoclasts that have become part of the bone framework.

The following diagram shows an osteocyte - a type of bone cell.

This diagram has been taken from Cancer Research UK's information about the bones.

Diagram showing an osteocyte - a type of bone cell

Last updated: 12 December 2014

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