Sarcomas, including soft tissue sarcomas, are rare types of cancer which develop in the connective tissues of the body. This includes bones, cartilage, muscles, and fat.
If a sarcoma is discovered at an early stage and hasn’t spread from where it originated, surgery is the often the primary treatment, aiming to completely remove the tumour.
With early diagnosis, a sarcoma can be treated aiming to cure it. However, if it has spread to other areas in the body, including lungs, bones and lymph nodes, known as metastatic disease, then it may be more challenging to treat.
What is the most common type of sarcoma?
Sarcoma is a complex disease that originates from different types of cells in the body. There are more than 100 subtypes of sarcoma, each with its own unique characteristics.
In the UK, the most common type of sarcoma is soft tissue sarcoma. Soft tissue sarcomas are a diverse group of cancers that originate from soft tissues in the body, such as muscles, nerves, fat, and blood vessels.
Within soft tissue sarcomas, there are many subtypes, including:
- liposarcoma
- leiomyosarcoma
- myxofibrosarcoma
It’s important to note that sarcomas are still considered rare compared to other types of cancer with approximately 4000 cases diagnosed in England each year, and their overall incidence is relatively low, representing less than 1% of all cancers diagnosed.
What are the causes of sarcomas?
Like most cancers, soft tissue sarcomas are typically caused by multiple factors, and not just a single identifiable cause.
However, generally speaking, changes to the DNA in the cells of connective tissues can lead to uncontrolled growth, which can ultimately cause the formation of tumours.
With that said, here are known causes and risk factors in sarcomas patients:
- Inherited syndromes – Certain genetic syndromes, such as Li-Fraumeni syndrome, familial retinoblastoma, and neurofibromatosis, can lead to an increased risk of developing a sarcoma.
- Exposure to radiation – If you have received any kind of radiotherapy in the past as part of cancer treatment, then you may be at a higher risk of developing a cancer, which can include a sarcoma.
- Exposure to chemicals – Exposure to certain chemicals may increase your risk, such as those used in making plastics and other chemicals which include arsenic, herbicides, and dioxin.
- Chronic swelling – Significant lymphoedema or swelling in the arms and legs for a prolonged duration may increase the risk of developing a sarcoma in the affected limb.
- Other risk factors – These may include viral infections such as the human herpesvirus 8 which can cause Kaposi’s sarcoma, and specific bone diseases which can also increase the risk of developing certain kinds of bone sarcomas.
Why sarcomas can be challenging to treat
Finding the best treatment for sarcoma in itself can be challenging and this is due to the rarity, variety, and likelihood of it developing in difficult-to-reach areas of the body. It is, after all, among the more rare cancers currently known in the medical space.
Here’s a more detailed breakdown of the challenges patients face:
Sarcomas are rare and diverse
Since sarcomas represent a rare group of cancers with many subtypes, it can be challenging to advise a universal treatment plan, and so treatment plans need to be tailored to the individual patient.
It is therefore very important to be seen by a doctor working in a specialist sarcoma team, to give access to the greatest clinical experience, and have the input of the whole multi-disciplinary team in agreeing on a treatment plan.
They can grow in any part of the body
Soft tissue sarcomas can develop in many different areas of the body, including the bones, muscles, blood vessels and nerves. If they develop close to vital structures, for example, nerves, spinal cord, blood vessels, surgery to remove the tumour can become complex and more challenging.
They can be undetected until they have spread to other parts of the body
Early diagnosis for sarcomas can be challenging in some cases; their symptoms can either be vague or mimic other health conditions.
This can result in a delay in diagnosis which may lead to more advanced disease with the primary tumour spreading to other parts of the body. This can make it difficult to treat the cancer curatively with the aim of completely getting rid of it.
Challenges of clinical trials in rare cancers
Clinical trials can be an important treatment option, which can give patients the opportunity to access a treatment that might not be otherwise available to them, and allows doctors to study the effectiveness and side effects of new treatments in order to understand if they should be adopted as part of standard treatment.
Clinical trials can cover all aspects of care, including surgery, radiotherapy, chemotherapy, diagnosis and follow-up after treatment, and are a very important part of improving patient care.
However, it is well recognised that carrying out clinical trials in rare cancers such as sarcoma can be difficult, because of the diverse range of sarcomas that all behave differently, and because of the relatively smaller number of patients available to take part in a clinical trial compared to commoner cancers.
Nevertheless, there are clinical trials being carried out for sarcoma patients, and it always worth asking your doctor if there is a trial that is suitable for you, or indeed researching this yourself on the internet.
What are the standard treatment options for localised sarcoma that has not spread?
Sarcomas can be treated in several ways. Treatment depends on a patient-to-patient basis, as it is determined by the type, grade, stage, and location of the sarcoma, as well as the patient’s general health.
Treatment options may include:
Surgery
Surgery is typically the primary treatment for sarcomas, where your surgeon will plan to remove the tumour completely, including a surrounding margin of healthy tissue, to minimise or prevent recurrence of the tumour in the future.
As sarcomas can arise in all sites of the body, many different types of surgeons may be involved, for example, orthopaedic surgeons, abdominal surgeons, head and neck surgeons.
Chemotherapy
Chemotherapy involves the use of cancer-treating drugs in order to kill cancer cells. When a tumour is diagnosed as a primary tumour with no signs of spread elsewhere in the body, chemotherapy is sometimes added to surgery, either before or after.
The decision on the need for chemotherapy is made by the multidisciplinary team, and is based on the sarcoma type, grade, location and stage. Not all tumours need chemotherapy as part of their primary treatment.
Radiation therapy
This treatment uses high-energy rays to destroy cancer cells and is often combined with surgery — either before, to shrink the tumour and make surgery more effective, or after, to help eliminate any remaining cancer cells, and reduce the risk of the tumour recurring at the site of surgery, in the future.
Radiotherapy is one of the most common treatments for sarcoma. Not all tumours need radiotherapy as part of their primary treatment, and the decision is based on tumour type, size, grade and surgical normal tissue margins, and is made by the multidisciplinary team.
Are there new treatments for sarcoma?
New drugs are being investigated for use in sarcomas for patients with advanced disease that has spread around the body, these can be accessed in clinical trials. However, there are also new advances in the local therapies used for treating sarcomas, including radiotherapy.
Proton beam therapy (PBT), an advanced form of radiotherapy, is a new treatment option for a number of cancers, including bone and soft tissue sarcoma.
Treatment for sarcoma using proton beam therapy involves highly targeted radiation using protons rather than the more usually used photons, sparing nearby healthy cells and tissues.
How does proton therapy differ from traditional radiation therapy for sarcoma?
Traditional radiotherapy delivers beams of photons or X-rays to the tumour site — and to tissues beyond, in what’s known as the exit dose. This means healthy surrounding tissue can also be exposed and potentially damaged. Such damage to otherwise healthy soft tissue can lead to significant side effects, potentially impacting long-term health.
Proton beam therapy, on the other hand, delivers a targeted beam of protons which deposits its energy at the primary tumour site, but does not travel on through the body and so has no exit dose. This reduces the radiation dose delivered to nearby normal tissues which can potentially reduce side effects.
Many sarcomas require high doses of radiation to be effective against the tumour, and this ability of proton beam therapy to deliver the optimal dose of radiation to the tumour while sparing normal tissues, means that it can be a good option for some sarcomas. This is particularly the case for sarcomas involving or close to the spine, brain, and heart and lungs.
Globally, a growing number of oncologists are recommending proton beam therapy as the preferred treatment option for suitable sarcomas.
To learn more about the difference between proton beam therapy and radiotherapy, read our blog.
Hope and innovation in sarcoma treatment
Being diagnosed with a sarcoma can be an incredibly difficult and uncertain time for patients and their families, particularly given their rarity, and the feeling of being alone with the diagnosis.
While sarcomas are undoubtedly rare and often complex to treat, there are skilled saroma teams who have the skill to treat these tumours, and a variety of treatment options available, including proton beam therapy which can offer an additional option for some patients, depending on the type, location, and stage of the tumour.
At Proton International London (PIL), our team of consultant radiation oncologists, proton beam therapy planners, and therapy radiographers plan and deliver highly targeted proton beam therapy that focuses precisely on the tumour, helping to minimise damage to surrounding healthy tissue.
Although proton beam therapy is not suitable for every patient, it may be considered as part of a personalised treatment plan, especially when conventional photon radiotherapy presents higher risks to nearby organs. Our role is to offer expert, balanced guidance, supporting patients and their specialist doctors in making informed choices about the best path forward.
Book an appointment now with complete peace of mind: 0203 9255 885.
Further reading:
