Soft tissue sarcoma occurs when the cells present in the soft tissues start dividing uncontrollably and form a tumor. There are several types of soft tissue sarcoma. The classification is required to determine the prognosis and appropriate treatment strategy. The staging of this condition is done according to the grade (aggressiveness) and size of the tumor.
Soft tissue sarcoma is a rare condition, and its incidence stands at 1.8–5 per 100,000 people per year. This sarcoma type constitutes 1–2% of all solid malignant neoplasms.
Several soft tissues are present in the body. These include tendons, muscles, blood vessels, nerves, and joint tissues. Soft tissue sarcoma occurs when the cells of these soft tissues grow uncontrollably, resulting in the formation of tumors, and it may develop in any soft tissue in the body. The most commonly affected soft tissues are the legs, arms, and abdomen. Soft tissue sarcomas are relatively rare compared to other types of cancer. This condition can affect children and adults, but adults are more commonly affected. The exact cause of this condition remains unknown, and the condition may occur spontaneously. Environmental factors and the presence of certain genetic factors enhance the risk of this condition.
There are several types of soft tissue sarcomas, and they are classified based on the tissues in which they occur. Some of the common types of soft tissue sarcoma in adults and children include:
Certain types of soft tissue sarcomas are more common in adults. The exact reason for this is unknown. The following are the types of soft tissue sarcomas commonly occurring in adults:
Liposarcoma is a soft tissue sarcoma tumor that develops from the connective tissues, particularly the fat cells. It is one of the most common soft tissue sarcomas in adults and accounts for about 20% of all adult soft tissue sarcomas. Liposarcoma can occur in any body part but is most frequent in the extremities (thighs or upper arms), the back of the abdominal cavity, and the inguinal area.
Some liposarcoma types include well-differentiated liposarcoma, myxoid liposarcoma, and dedifferentiated liposarcoma.
Patients with liposarcoma experience painless swelling or lumps, and the condition is usually diagnosed with imaging studies (CT and MRI) and a biopsy. The prognosis of liposarcoma depends on various factors, including the stage of diagnosis, response to treatment, and the affected body organ.
It is also a common subtype of soft tissue sarcoma in adults. It occurs in the smooth muscle cells. These cells are present in various body parts, including the gastrointestinal tract, uterus (uterine leiomyosarcoma), and blood vessels. Uterine leiomyosarcoma is a rare but aggressive form of leiomyosarcoma. Patients may have a painful palpable mass and other symptoms specific to the tumor location. Regarding prognosis, uterine leiomyosarcoma has a relatively poor prognosis compared to other leiomyosarcoma subtypes.
Undifferentiated pleomorphic sarcoma was previously known as malignant fibrous histiocytoma (MFH). This condition is characterized by a lack of differentiation. In this sarcoma, the tumor cells do not resemble any specific type of normal tissue cells. Undifferentiated pleomorphic sarcoma is a high-grade and aggressive form of sarcoma and can occur in various soft tissues, including the legs, arms, trunk, and retroperitoneum. It grows rapidly and has the potential to metastasize to other body parts quickly. Given its aggressive nature and rapid metastasis, early diagnosis and prompt management improve outcomes in patients with undifferentiated pleomorphic sarcoma.
Certain types of soft tissue sarcoma are more common in children, and they include:
Rhabdomyoblasts are the precursors to skeletal muscle cells. Rhabdomyosarcoma arises from rhabdomyoblasts. It is one of the most common types of soft tissue sarcoma in children. The two main types of rhabdomyosarcoma are embryonal rhabdomyosarcoma and alveolar rhabdomyosarcoma. The most common sites for this condition include the head and neck region and the genitourinary tract. The symptoms include pain, the presence of a visible mass, and swelling. The other signs are specific to the location of the tumor. Compared to adults, the overall survival rate for rhabdomyosarcoma is better in children.
It is also a type of soft tissue sarcoma in children. Ewing sarcoma usually occurs in the bones. However, it may also occur in the soft tissues of some patients. Ewing sarcoma of the soft tissues commonly occurs in the abdominal wall, chest wall, and other soft tissue locations. The symptoms experienced by the patients include pain, swelling, lumps, functional impairment, and limited range of motion. The diagnosis of the disease is confirmed by the presence of an EWSR1 gene rearrangement detected through genetic testing. The prognosis is relatively better in patients with early disease diagnosis and prompt treatment.
Several factors affect the seriousness and severity of this condition. These factors include types of soft tissue sarcoma, tumor location, size, grade of tumor, and extent of tumor spread. High-grade aggressive sarcomas have a relatively poor prognosis. Further, sarcomas of the extremities, such as legs or arms, have a relatively better prognosis than those in critical locations, such as the neck, head, or retroperitoneum. Some subtypes of soft tissue sarcoma have high resistance to treatment and have high recurrence potential. Patients with those subtypes have a poor prognosis.
Stages of soft tissue sarcoma include:
It is an early-stage soft tissue sarcoma. At stage 1, the tumor is of low grade (grade 1) and may be of any size. Nearby lymph nodes or distant organs are not affected.
The tumor at stage 2 is of grade 2 or grade 3. The tumor size is <5 cm. It has not affected the surrounding lymph nodes or the distant organs.
Stage 3 soft tissue sarcoma is of grade 2 or 3. The size is greater than 5 cm but not more than 10 cm (stage 3A) or greater (stage 3B). It has not affected the surrounding lymph nodes or the distant organs.
The stage 4 soft tissue sarcoma refers to a tumor that may be of any size and either spread to the nearby lymph nodes (stage 4A) or distant organs such as the liver (stage 4B). The tumor may be of any grade.
Soft tissue sarcoma, a rare cancer, may present as painless lumps or swelling. Symptoms are not presented in the early stages. Causes include genetic factors and radiation therapy. Early detection improves treatment outcomes.
Patients may have soft tissue sarcoma signs based on the tumor size and location. Some of the soft tissue sarcoma cancer symptoms include:
Lumps may be one of the most common soft tissue sarcoma cancer symptoms. The lump is usually painless. However, in some patients, painful lumps may be present. A lump may raise concerns about soft tissue sarcoma, especially in the legs, arms, or trunk. Patients with painless lumps in the initial stage may experience pain later due to pressure on the nerves by the lump. This is also one of the classic symptoms of soft tissue cancer in the leg.
A fast-growing lump may also be a soft tissue sarcoma sign. Although the growth rate of soft tissue sarcoma tumors is unpredictable, any tissue growth or lump should be immediately brought to the attention of a healthcare provider. A fast-growing lump, along with a change in texture and limited mobility, raises concerns about the presence of soft tissue sarcoma.
Abdominal pain may also be a soft tissue sarcoma sign, especially when the tumor grows in the abdominal region. Sarcoma in the uterus may also cause abdominal pain. Patients with persistent abdominal pain should consult the doctor for an appropriate diagnosis and optimal treatment. It is important to note that soft tissue sarcoma is not the primary consideration for abdominal pain, as several other less serious conditions may cause abdominal pain. However, abdominal pain should not be ignored and should be evaluated by the doctor.
Nausea and vomiting are not the common soft tissue sarcoma cancer symptoms. However, if the patients have soft tissue sarcoma in the abdominal region, they may experience nausea and vomiting. During the advanced stages of the disease, the abdominal sarcoma grows in size and obstructs the normal functioning of the digestive tract, resulting in nausea and vomiting.
Unexplained weight loss may also be a soft tissue sarcoma sign. There are several causes of weight loss in patients with soft tissue sarcoma. These include reduced appetite, increased metabolism, malabsorption, and treatment-related side effects. Weight loss is more prominent in the advanced stages of the disease when the cancer invades other body parts.
Tarry stools may also be a soft tissue sarcoma sign, especially when the tumor grows in the abdominal cavity. The tarry stools suggest internal bleeding in the gastrointestinal tract. In advanced stages, the cancer may spread from the primary site to the abdominal regions and may cause blood in the stools.
Soft tissue sarcoma is not an easily recognizable condition due to non-specific symptoms. Advanced diagnostic techniques, such as MRI, CT scans, or biopsy, are required for diagnosing soft tissue sarcoma. Soft tissue sarcoma cancer symptoms, such as lumps, abdominal pain, nausea, vomiting, and tarry stools, are also the symptoms of various other conditions. The doctor should evaluate any new lump or rapid change in the size of the pre-existing lump. The appearance of the soft tissue sarcoma lump varies depending on the specific type of soft tissue sarcoma.
Several patients inquire about what causes sarcoma cancer. Some of the soft tissue sarcoma causes include:
While most soft tissue sarcomas are not directly associated with inherited or genetic disorders, certain genetic conditions increase the risk of developing these tumors and serve as possible soft tissue sarcoma causes. The following are the genetic disorders that are associated with the possible development of soft tissue sarcoma:
It is a rare genetic disorder that is caused by mutations in the TP53 gene. Individuals with Li-Fraumeni syndrome have a higher risk of developing various types of cancer, including soft tissue sarcomas.
It is a genetic disorder caused by an NF1 gene mutation. In several cases, patients with NF1 develop benign tumors, such as neurofibroma. However, in some cases, patients with NF1 develop malignant peripheral nerve sheath tumors.
People with Gardner syndrome have an enhanced risk of various tumors, including soft tissue sarcomas.
History of radiation therapy is also one of the possible soft tissue sarcoma causes. The risk of soft tissue sarcoma is higher in patients who have undergone radiation therapy, especially at a younger age.
Lymphedema is a condition that involves the accumulation of fluid in the tissues, resulting in swelling. Patients suffering from chronic lymphedema, which is caused by surgical removal of the lymph nodes or radiation therapy to the lymph nodes, are at higher risk of developing soft tissue sarcoma.
Exposure to certain chemicals is also one of the possible soft tissue sarcoma causes. These chemicals include dioxins, chlorophenols, phenoxy herbicides, and vinyl chloride.
Patients with HIV infections are at higher risk of developing several types of cancer, including soft tissue sarcoma. It is mainly due to the compromised immune system in such patients.
Patients should not ignore soft tissue sarcoma cancer symptoms, such as lumps, abdominal pain, nausea and vomiting, and blood in stools. Consult an oncologist if the patients experience these or additional symptoms that cause concern.
Soft tissue sarcoma diagnosis involves blood tests, imaging studies, and biopsy. Treatment may include surgery, radiation therapy, chemotherapy, targeted therapy, or immunotherapy. A multidisciplinary team approach is required to develop customized treatment plans and improve overall outcomes. The survival rate for soft tissue sarcoma depends on several factors.
Multiple tests are available for soft tissue sarcoma diagnosis. The following are the commonly recommended techniques for soft tissue sarcoma diagnosis:
The patients consulting the doctor for their symptoms undergo a comprehensive physical evaluation to determine the appropriate cause of the symptoms. The doctor may inquire about the severity of the symptoms. They may also ask about the onset and progression of the symptoms. The healthcare provider examines the affected area and assesses the pain, mobility, and any neurological symptoms.
The medical history of the patients and their family history are important considerations for soft tissue sarcoma diagnosis. Patients with a history of soft tissue sarcoma have a higher chance of developing the disease again, and the doctor should evaluate any symptoms at the same or any other place. Certain genetic syndromes also increase the risk of soft tissue sarcoma. Studies suggest that individuals with a family history of soft tissue sarcoma have a slightly higher risk for this disease. Thus, evaluating family history is important for soft tissue sarcoma diagnosis.
Blood work is not primarily recommended for soft tissue sarcoma diagnosis. However, they may provide crucial information about the patient's overall health. Further, specific blood tests also inform about the metastasis of soft tissue sarcoma to specific organs. Blood tests are also helpful during chemotherapy treatment to detect the levels of blood cells. Some patients with soft tissue sarcoma have elevated levels of lactate dehydrogenase. C-reactive protein and erythrocyte sedimentation rate are linked with inflammation and should be monitored to evaluate the presence of systemic inflammation.
X-rays are not usually the primary imaging technique for soft tissue sarcoma diagnosis. This imaging technique is ineffective for soft tissue scans, such as connective tissues and muscles, where soft tissue sarcoma usually develops. However, the doctors may recommend an x-ray examination if bone involvement is suspected in patients with soft tissue sarcoma.
Computed tomography is an effective imaging modality for soft tissue sarcoma diagnosis. The technique provides comprehensive and clear cross-sectional images of various body soft tissues where soft tissue sarcoma is suspected. A CT scan provides important information about the location, size, and other characteristics of the soft tissue sarcoma. The technique also assists oncologists in detecting any bone involvement or bone damage caused by the tumor. CT scans also effectively evaluate the vascular system near the soft tissue sarcoma and examine the vascular invasion. Oncologists recommend computed tomography to stage the disease, which assists in treatment planning and monitoring responses to treatment. However, it is important to consider ionizing radiation in the CT scan, especially when repeated imaging is required.
MRI is also an important imaging modality for soft tissue sarcoma diagnosis. Soft tissue MRI provides detailed, high-resolution images of the soft tissues and effectively demarcates the extent of the tumor. It is highly effective for detailed visualization of the soft tissues, including ligaments, muscles, tendons, and other soft tissues. Like CT scans, MRI also assists oncologists in determining the location, size, and cellular characteristics of the tumor. This information is used to determine the type and aggressiveness of the cancer. The scan also helps provide information about the involvement of nearby structures, such as nerves and blood vessels. The images provided by the MRI are obtained from multiple angles, helping to detect the tumor precisely. MRI helps in staging the cancer and assists the oncologists in planning the treatment. Once the treatment is started, the oncologists may use MRI to monitor the treatment response.
A PET scan is also an important imaging technique used in soft tissue sarcoma diagnosis as it provides valuable information regarding the metabolic activity of the abnormal tissues. PET scans measure the uptake of a radioactive glucose analog to determine metabolic activity. A PET scan is a complete body scan; this helps specialists determine the site of the primary tumor and possible metastases. Staging the disease is done through the results provided by the PET scan, as it assesses the spread of the tumor to nearby structures, lymph nodes, and distant organs. PET scans can help differentiate between scar tissue and active tumors, offering important information for clinical decision-making. Doctors may also recommend PET scans to monitor the treatment response and evaluate recurrence, especially in high-risk patients.
Ultrasound is not a preferred imaging technique for soft tissue sarcoma diagnosis. However, doctors may recommend this imaging technique to evaluate the superficial mass or during a biopsy (ultrasound-guided biopsy). It provides a real-time image of the abnormal site, helping visualize the tumor mass and surrounding structures. Ultrasound may also examine blood flow within the tumor and surrounding tissues. Increased vascularity may suggest certain types of soft tissue sarcomas. Ultrasound may be preferred over other imaging techniques that involve ionizing radiation in pediatric patients or pregnant women.
A biopsy is recommended as a confirmatory test for a soft tissue sarcoma diagnosis. It involves obtaining a tissue sample from the suspicious area for pathological examination. While imaging tests, such as CT scans and MRIs, provide valuable information about the characteristics, location, and extent of the tissue mass, a biopsy confirms the presence of soft tissue sarcoma. Several techniques are implemented in the biopsy. These include a needle biopsy, an incisional biopsy, and an excisional biopsy. A biopsy is also performed under the guidance of various imaging techniques, including ultrasound, MRI, and CT scans.
Once the samples reach the laboratory, the pathologists examine them under the microscope. Pathologists provide detailed information about the types of cells present, the grade of the tumor, and other characteristics that help diagnose and classify soft tissue sarcoma. Oncologists develop appropriate treatment strategies based on the results of the biopsy.
Once the diagnosis is confirmed and the staging is confirmed, specialists begin devising a customized treatment plan based on the type of soft tissue sarcoma, its stage, its grade, the patient’s overall health, etc. The following are the different options available for soft tissue sarcoma treatment:
Surgery is often the primary line of soft tissue sarcoma treatment. The surgery aims to remove the tumor while preserving function and lowering the risk of recurrence. The extent and type of surgery depend on various factors, such as the size, location, grade, and stage of the sarcoma. Some soft tissue sarcoma surgery techniques include wide local excision, limb-sparing surgery, sentinel lymph node biopsy, amputation, and reconstruction. Surgery is usually the only treatment required in patients with localized soft tissue sarcoma. However, in patients with advanced disease, surgery usually accompanies other soft tissue sarcoma treatments, such as radiation therapy and chemotherapy.
Soft tissue sarcoma chemotherapy is a systemic treatment that uses drugs to kill or delay the growth of cancer cells throughout the body. Chemotherapy as a soft tissue sarcoma treatment is used along with surgery or in the treatment strategy for patients with metastatic soft tissue sarcoma. Drugs under chemotherapy are used in combination to improve the outcomes. Chemotherapy for soft tissue sarcoma includes adjuvant chemotherapy, neoadjuvant chemotherapy, and palliative chemotherapy.
Soft tissue sarcoma radiation therapy is a common treatment modality. Radiation therapy for soft tissue sarcoma treatment is used at different stages of the disease to target and kill cancer cells. The technique may be adjuvant radiation therapy, neoadjuvant radiation therapy, brachytherapy, external beam radiation therapy, and intensity-modulated radiation therapy. In case the surgery is not feasible, radiation therapy may be considered as the definitive therapy for soft tissue sarcoma treatment. In addition, radiation therapy may also be recommended as a part of palliative care to improve the symptoms of advanced and metastatic soft tissue sarcoma.
Targeted therapy for soft tissue sarcoma involves administering the drugs specifically targeting molecules or pathways vital for cancer cells' growth and survival. Unlike traditional chemotherapy, which affects rapidly dividing cells throughout the body, targeted therapies interfere specifically with the cancer cell function. The targeted therapy's side effects are relatively fewer than traditional chemotherapy. Different classes of drugs used in targeted therapy for soft tissue sarcoma treatment include tyrosine kinase inhibitors, mTOR Inhibitors, PD-1/PD-L1 Inhibitors, KIT Inhibitors, fibroblast growth factor receptor inhibitors, and hormone receptor inhibitors.
Immunotherapy improves the body's immune system to recognize and attack cancer cells. It is an effective soft tissue sarcoma treatment. Cancer cells evade the damaging effects of the immune system through certain cellular processes. Immunotherapy interferes with these processes and makes the cancer cells sensitive to the immune system. Some of the drugs used include immune checkpoint inhibitors and PD-1 inhibitors.
Palliative care is provided to patients with advanced and metastatic soft tissue sarcoma. Palliative care aims to manage the symptoms, provide emotional and psychological support, and improve the quality of life of the patients. Surgery, radiotherapy, and chemotherapy are usually the components of a palliative care strategy. Patients with advanced-stage soft tissue sarcoma that is untreatable and progressive may have the option to register themselves for soft tissue sarcoma clinical trials.
The choice of a hospital for soft tissue sarcoma diagnosis and treatment depends on various factors, including the hospital's expertise in sarcoma care, the range of treatment options offered, the availability of modern facilities and soft tissue sarcoma specialists, and the overall quality of medical care provided. HCG offers comprehensive medical care to patients suffering from soft tissue sarcoma. The hospital also has the latest imaging techniques to diagnose and stage the disease accurately.
Several factors enhance the risk of soft tissue sarcoma. Clinicians must identify those risk factors and provide appropriate preventive measures to lower the risk of developing soft tissue sarcoma.
Some of the common soft tissue sarcoma risk factors include:
Age is a non-modifiable soft tissue sarcoma risk factor. Although soft tissue sarcoma may occur at any age, the risk rises as age increases. The disease may also affect adolescents and children. Older adults have a higher risk of developing soft tissue sarcoma than younger adults. The condition is most frequently diagnosed in individuals between 50 and 70. The age-related patterns vary according to the soft tissue sarcoma subtypes.
The history of radiation therapy is one of the soft tissue sarcoma risk factors. The use of ionizing radiation during radiation therapy may result in gene mutations that may transform healthy cells into malignant cells. Soft tissue sarcoma may have a latency period, meaning that the cancer may occur after several years of radiation therapy. The risk of soft tissue sarcoma increases with high radiation doses, more sessions, or a higher frequency of sessions. The oncologists need to monitor the patients for soft tissue sarcoma or other secondary cancers after radiation therapy.
People with excessive radiation exposure are at increased risk of developing soft tissue sarcoma. Exposure to radiation during the imaging techniques is also a soft tissue sarcoma risk factor. Certain occupational and environmental radiation exposures may also enhance the risk of soft tissue sarcoma. These include excessive exposure to solar radiation or radiation from nuclear power plants.
Exposure to certain chemicals is one of the soft tissue sarcoma risk factors. These chemicals include vinyl chloride (used in the production of plastics), dioxins (found in herbicides and other industrial processes), chlorophenols (used in the production of disinfectants and pesticides), and phenoxy herbicides.
Although family history is a soft tissue sarcoma risk factor, most cases occur spontaneously in patients with no family history. Specific genetic syndromes and hereditary conditions enhance the risk of soft tissue sarcoma. These include retinoblastoma, Garner syndrome, neurofibromatosis type 1, and Li-Fraumeni syndrome.
The immune system has a vital role in detecting and killing the abnormal cells present in the body. The compromised immune system is a modifiable soft tissue sarcoma risk factor. Patients with poor immune systems, such as HIV and AIDS, are at a higher risk of developing soft tissue sarcoma.
Patients with lymphedema have a slightly increased risk of developing soft tissue sarcoma. The condition involves fluid accumulation in the tissues that results in swelling. Lymphedema may be caused by the removal of the lymph nodes by radiation therapy or surgery.
Children born with an inguinal or congenital umbilical hernia are at increased risk of developing sarcoma. The reason for this association is not clear.
Although it is impossible to prevent soft tissue sarcoma, certain soft tissue sarcoma prevention measures lower its risk. Soft tissue sarcoma prevention strategies include minimizing modifiable risk factors and adhering to a healthy lifestyle. Some soft tissue sarcoma prevention measures are:
Minimizing exposure to ionizing radiation from medical treatments or occupational sources may lower the risk of radiation-induced soft tissue sarcomas.
Reducing exposure to harmful chemicals in the workplace or the environment, following safety guidelines, and using protective measures while working with harmful chemicals can reduce the risk of soft tissue sarcoma.
Individuals with a family history of soft tissue sarcoma or those who are suffering from genetic syndromes that enhance the risk of soft tissue sarcoma should be provided genetic counseling. Information should be obtained about their risk of developing soft tissue sarcoma.
Like other cancers, a healthy lifestyle reduces the risk of soft tissue sarcoma. It helps improve the immune system and enhances the body's ability to fight against abnormal cells. Engaging in regular physical activity may prevent cancer. A well-balanced diet comprising vegetables, fruits, and whole grains supports a healthy immune system.
Excessive exposure to solar radiation should be avoided to lower the risk of soft tissue sarcoma. It includes going out in the sun only when necessary and using sunscreen lotions.
It is important to consult the oncologists immediately if any symptom may cause concern, especially in people with a high risk for soft tissue sarcoma or individuals with a history of soft tissue sarcoma. Early detection helps with appropriate intervention and improves overall outcomes.
Soft tissue sarcoma originates from the soft tissues, such as connective tissues, blood vessels, and nerves. The types of soft tissue sarcomas include liposarcoma, leiomyosarcoma, and undifferentiated pleomorphic sarcoma in adults and rhabdomyosarcoma and Ewing sarcoma in soft tissue in children. Based on the extent of the disease’s growth and spread, this condition is staged between stages 1 and 4, with stage 1 referring to the early-stage disease and stage 4 referring to the advanced stage of the disease.
