Sarcoma is a rare malignant disease beginning from soft tissues or bones. Because they hardly cause any pain, sarcomas are often dismissed as harmless swellings at first. Treatment methods include surgery, chemotherapy or local chemo (transarterial chemoembolization and chemoperfusion), immuno-, target, radiation (including internal), and proton beams.
Sarcomas are malignant tumors that originate in the connective or supportive tissue of the body. They affect cells of muscle, fat, cartilaginous connective, and bone tissues. In addition, the tumor can involve blood and lymphatic vessels and nerves.
The disease can occur anywhere in the body. However, doctors distinguish between so-called soft tissue sarcomas and sarcomas of the skeletal system. Important subtypes of the disease:
- Soft tissue sarcomas
- Connective tissue sarcomas;
- Sarcomas of adipose tissue;
- Sarcomas of smooth muscle tissue.
- Bone sarcomas
- Osteosarcoma (originating in bone tissue);
- Chondrosarcoma (starting in cartilage tissue);
- Ewing's sarcoma (arising mainly in bone tissue).
According to the cells, the disease has its classification, which includes about 100 types. Since sarcoma does not belong to any organ, these neoplasms are classified according to the tissues in which they were found.
Statistics say that just over 1% of all cancers are sarcomas. The larger group is soft tissue tumors. Bone sarcomas are even rarer. However, the disease is more common among children - it accounts for 15% of all types of malignant neoplasms. It is considered dangerous because it is characterized by frequent relapses and the rapid appearance of metastases that spread throughout the body.
Causes for sarcoma
In most cases, the oncologist cannot identify a clear cause for sarcoma. However, experts have established some factors that can lead to the disease. At the same time, the presence of one or more signs from the list does not necessarily indicate the appearance of the tumour.
- Heredity plays a relatively minor role. However, if close family members already have cancer, there may be an increased risk of developing the disease.
- Radiation therapy in connection with another disease can, in rare cases, promote sarcoma development.
- Environmental toxins and chemicals (wood preservatives, herbicides, dioxin or arsenic) and chronic inflammation also appear to form soft tissue sarcomas.
- Smoking and excessive alcohol consumption are also risk factors.
What can be sarcoma signs?
Usually, the disease is symptomatic and fast-growing. Therefore, patients may suffer from compressing the nearby organs by malignant tissue. Symptoms of sarcoma can be:
- Painless swelling;
- Lymph node swelling;
- The pain of unclear origin;
- Local signs of inflammation (reddening, swelling, overheating);
- Functional limitations due to the growth of the sarcoma;
- Pathologic fractures (bones broken by a minor impact);
- Night sweats, fever, pallor and a general feeling of illness.
Pain does not occur immediately. It develops when the tumour affects the nerve tissues. The pain becomes severe and spreads in different directions (irradiate). It intensifies at night, and painkillers usually do not help. If you notice an unusual area, you should immediately consult a doctor. Sometimes a few weeks are enough to progress from localized sarcoma (which can be successfully treated) to advanced metastatic disease (4th stage sarcomas is hard to treat).
If the tumour occurs close to the external tissues, it should be visible (a palpable nodule). At first, the knot is soft and elastic. However, as it grows, several forming centres are noticed in it. The colour of the skin changes, and pain occurs under pressure. The final sarcoma size can reach 30 centimetres in diameter, sometimes even more.
Along with local symptoms, a general malaise can appear. Patients constantly feel broken, tired, and lose weight. They lose their appetite and complain of nausea and vomiting. It is due to intoxication. For the same reason, the temperature rises and does not disappear after medications. Blood tests reveal anaemia and signs of severe inflammation.
How do oncologists diagnose sarcomas?
For sarcoma diagnosis, various studies can be conducted that add information to the general picture. They help the clinical oncologist determine the stage, type and localisation of the malignant tumour. After the initial examination, the doctor prescribes a list of tests:
Imaging (scans) is a primary method for proper diagnosis. As with any malignant condition, doctors should check the sarcoma's location and size:
- An X-ray gives the doctor the first orientation. Then, he can see the soft tissue shadows in the picture. The method is also suitable, for example, for localising metastases in the lungs.
- Magnetic resonance imaging (MRI) is the most informative diagnostic method for soft tissue sarcomas on the arms and legs. Using the images, specialists determine the position and size of the sarcoma.
- Computer tomography (CT) images show a cross-section of the organs in the abdomen or chest, the brain or the lymph nodes. Using CT, oncologists determine the location and extent of soft tissue sarcomas. In addition, PET-CT scans can be used in advanced diseases when doctors require checking metastases.
- Ultrasound examination (sonography) shows changes in the tissue. In contrast to most benign soft tissue tumours, malignant soft tissue sarcomas are very well supplied with blood, which we can detect using modern ultrasound devices.
A biopsy is always needed to determine the type and aggressiveness of the soft tissue tumour. In addition, it is crucial to plan the following therapy. Depending on the biopsy results, doctors differentiate between four stages of sarcoma:
- Stage I - describes a localised sarcoma that has not affected any lymph nodes and organs.
- Stage II - is less than 5 cm sarcoma without lymph node involvement and metastases.
- Stage III - is the sarcoma to over 14 cm, lymph nodes can be involved, and no metastases are present.
- Finally, stage IV - refers to any tumour, regardless of size and grade, that has distant metastases.
Treatment strategy for sarcomas
Cancer treatment involves using several methods to achieve a positive result. The primary option for sarcomas is surgical intervention. In addition, chemotherapy and radiation therapy delivers a complex effect and help prevent tumour metastasis to distant tissues and organs.
Surgery is the treatment of choice for soft tissue sarcoma. Especially if the malignant cells are well differentiated and there are no metastases, the chances are high that the doctor can remove the tumour altogether. If possible, the surgeon also cuts out some healthy tissue around the malignant neoplasm. It reduces the risk that sarcomas will reappear at this point (local recurrence). Limb-salvage (limb-sparing) surgery means removing a tumour in a limb (arm or leg) without removing the whole extremity. Up to 20% of soft tissue sarcomas are only diagnosed today through an unplanned operation (so-called "whoops"). It happens when swelling is operated on to analyse it then. Some patients might require surgical reconstruction, joint replacement or prosthesis after sarcoma surgery.
Radiation therapy is a standard method before, during, or after surgery. Radiotherapy can help prevent the sarcoma from forming again (recurrence) by destroying individual cancerous cells that may have remained after surgery. As a single measure, however, it is often not sufficient. One of the radiation types is brachytherapy (internal radiotherapy). In addition, it is contact radiation therapy for sarcomas treatment, which involves the installation of radioactive drugs directly into the tumour. Proton therapy is the most advanced radiation option. It uses high-powered energy, which is safer and more targeted than conventional radiotherapy. It kills malignant sarcoma cells and has minimal effect on surrounding tissues.
Chemotherapy is an option if the sarcoma is aggressive and tends to metastasise. It acts systemically and can also kill individual malignant cells before they grow into new daughter tumours. In addition, there are more specific types of chemotherapy:
- Transarterial chemoembolisation (TACE) - is the injection of drugs into the vessel feeding cancerous cells. The simultaneous blockage of this artery kills metastasis.
- Transarterial chemoperfusion (TACP) - is an introducing antitumour drug into the arteries feeding the sarcoma.
Also, more modern methods of therapy are now available for sarcoma treatment. They provide a targeted approach to malignant neoplasms without invasive intervention and damage to normal tissues:
- Cancer immunotherapies use unique properties of the tumour cells to support the body's immune system in the fight against sarcoma.
- Targeted therapies can also be used for sarcomas, depending on the properties of the cancerous cells. An example of this is tyrosine kinase inhibitors. They suppress a specific signal that the tumour cells need to grow and slow the malignant cells' pathological development.
- Cancer vaccines - use dendritic cells to activate them against sarcomas to eliminate the tumour. Dendritic cancer vaccines are newly developed that can be used in advanced sarcoma treatment.
What are the chances for successful sarcoma treatment?
The prognosis of sarcoma depends on the tumour stage, age and the patient's general condition. In the case of early diagnosis, the forecast is good: the 5-year survival rate is 85 to 96%. It is 72 to 78% in stage II, 50% in stage III and 10% in stage IV. However, about 80% of recurrences occur within the first two years.
People diagnosed at an early phase with the tumour localised in the extremities have the most excellent chance of survival. 75% of them overcome the five-year milestone. Sarcoma in the body and internal organs reduce survival to 60%. If cancer cells have spread, only 35% of patients can be saved.
How is Kaposi sarcoma treated?
Treatment methods for sarcoma include surgery (radical removal and limb-sparing operation), chemo- (transarterial chemoembolization and chemoperfusion), immuno-, target, radiation, proton, and brachytherapy.
Is Ewing sarcoma curable?
About 70% of children with Ewing sarcoma are curable. However, teens aged 15 to 19 have a lower survival rate of about 56%. The survival rate for children with metastatic Ewing sarcoma is less than 30%.
Why do sarcomas spread fast?
Soft tissue sarcoma affects muscle, blood vessels, connective fibres, and fatty tissue. It is most often localised in the mammary glands, limbs, large vessels and organs of the gastrointestinal tract. Rapid development is associated with the fact that all the tissues mentioned above are characterised by active natural growth, especially at a younger age. Also, the malignant process often affects the walls of blood and lymphatic vessels. Therefore, rapid metastasis is a widespread phenomenon.
What is the best treatment for sarcoma?
Because of the high prevalence of the process throughout the body, the best treatment is systemic chemotherapy. But, of course, a complex approach has the most positive results. In addition, if the sarcoma has not had time to spread, then surgical removal, in this case, is the best option.
What alternative treatment is available for sarcomas?
Such modern methods as brachytherapy (targeted irradiation of the neoplasm) and proton therapy (with the help of proton beams) allow treating sarcomas with minimal damage to the surrounding tissues. The USA FDA has granted accelerated approval to olaratumab (Lartruvo®) for treating some patients with soft tissue sarcoma.
Where can I get Sarcoma treatment?
What are the best clinics for Sarcoma treatment?
Who are the best doctors for Sarcoma?
Prof. Dr. med. Thomas J. Vogl from University Hospital Frankfurt am Main of Goethe-University
Dr. med. Anett Tillmann, MBA from Academic Hospital Bundeswehr Berlin
Prof. Dr. med. Roland Ladurner from Academic Hospital Martha-Maria Munich
Prof. Dr. med. Stefan Hinterwimmer from ATOS Orthopaedic Clinic Munich
Prof. Dr. med. Alexander Muacevic from European Radiosurgery Centre Munich