Tumour Frequently Asked Questions

Resources and Answers

FAQ on Tumour

What is a Tumour?
A tumour literally means a lump. We generally take a tumour to mean a neoplasm or “new growth”. Most tumours are benign, which means that they have the potential to grow locally but they do not typically spread or represent a threat to life. If they are causing symptoms or are likely to cause problems if they grow too big, then it is usually recommended to remove them surgically. Some tumours can be managed without the need for surgery. Occasionally, benign tumours can undergo change into a malignant tumour or “cancer”.
What are Benign Tumours?
Benign tumours are new growths that arise when cells mutate and lose their normal regulatory control. This allows the cells to multiply until they form a lump. They typically have a capacity to grow locally, but they do not typically spread to other sites or represent a threat to life.

Examples of common benign tumours are listed below.

A lipoma is a benign growth of fat tissue. They are commonly small and superficial but may grow very large and occur deep within muscles. They occur all over the body. They usually grow very slowly and can undergo malignant change when they enlarge.

Nerve tumour
Benign nerve tumours may arise in the nerve (Neurilemmoma) or from the insulating cells that surround them (Schwannoma). They are often very sensitive and may cause pain. They grow slowly but can undergo malignant change. If they are symptomatic, surgery is usually recommended.

Enchondromas are the most common benign tumour of bone. They are usually found as an incidental finding when an x-ray or MRI scan has been performed for other reasons. Malignant change is very unusual but larger lesions will usually require distinction from its malignant cousin – the chondrosarcoma. This will usually require a number of investigations or a period of observation.

An osteochondroma is a developmental tumour that results in a bony lump extending from the surface of a bone, typically near a joint. They arise from juvenile growth plates within the bone and grow as the skeleton matures. Where they cause symptoms they can be resected.

Osteoid Osteoma
Osteoid osteoma is a benign bone tumour that typically affects adolescents and young adults, although it can occur at any age. It is characterised by bone pain, especially at night and will often wake affected people from their sleep. It has usually been present for some time before diagnosis is made. The tumour has a typical appearance as a “nidus” or seed that sits within a cocoon of reactive new bone. This new bone is often obvious as a bony swelling. Once the diagnosis is confirmed, it is usually treated by surgery. In the past, treatment required complete excision of the nidus. This was difficult to achieve accurately. In the late 1990’s radio frequency ablation (RFA) became available, allowing clinicians to burn the nidus via a needle placed directly inside it under CT scanner guidance. This procedure is usually performed under a General Anaesthetic. RFA for osteoid osteoma was introduced into Australia by Dr Powell in 1998. It is now the gold standard of care for treatment of this tumour.

Pigmented Villo-Nodular Synovitis (PVNS) is a benign but often aggressive condition that occurs in joints. It almost always affects a single joint and results in pain and swelling. It arises in 2 distinct forms. The localised form is usually easily controlled with surgical resection and recurrence is uncommon. The more diffuse form of the disease may be difficult to control and may require multi-modal management, depending upon symptoms. It can result in arthritis in chronic cases.

A gangion cyst is a degenerative gelatinous collection that arises from joints or tendon sheaths. They tend to come and go. They are often small. When they cause symptoms they may be aspirated but there is a tendency for them to recur and they may then warrant excision.

What are Malignant Tumours?

Malignant tumours are growths that can invade local tissues and spread to other parts of the body (metastasis). In common parlance they are called cancers. Not all cancers are the same and treatment will depend specifically on the type. Cancers may be primary – i.e. arising in the local tissues – or secondary, where they have spread (metastasized) from a primary site to the location where they are discovered. Bone is a common site for secondary metastases from other sites, including lung, breast, kidney, prostate, thyroid etc.

What types of Malignant Tumours are there?


Malignant tumours that arise from the connective tissues that bind us together (bone, muscle, tendon, cartilage, blood vessels, nerves) are called sarcomas. These are very rare tumours and make up only about 1% of all adult cancers. It is estimated that an average GP might see one in their working lifetime. Many sarcomas can be cured and the best likelihood of this is if they are treated by a sarcoma specialist within a multidisciplinary sarcoma service.

Sarcomas are generally divided into sarcomas affecting bone (osteosarcoma, chondrosarcoma, and Ewing Sarcoma) or soft tissue sarcomas (MFH, UPS, liposarcoma, fibromyxoid sarcoma, PNET, synovial sarcoma, epithelioid sarcoma etc.)


Bone Cancer

Many different types of cancer may affect the bone.

The most common type is metastasis of a carcinoma or melanoma that has spread from another part of the body. These are called secondary cancers.

Primary cancers can also arise in the bones. In older patients, these include lymphoma and multiple myeloma, but may also be due to sarcoma.

In younger patients primary cancers of bone are more likely to be a sarcoma and include Osteosarcoma and Ewing Sarcoma. It is very important to identify these correctly to ensure that correct management is instituted at an early stage.

​Useful Links

Types of Sarcoma

Soft Tissue Sarcoma


Ewing Sarcoma




Sarcoma Resources in Australia

Cancer in Adolescents and Young Adults (CanTeen)

Australia & New Zealand Sarcoma Association (ANZSA)

Peter MacCallum Cancer Institute (Sarcoma Service)