Paediatric Soft Tissue Sarcomas: Comprehensive Cancer Information

Paediatric Soft Tissue Sarcomas: Overview

General Information

Soft tissue sarcomas (STS) represent a diverse group of cancers that begin in the supportive and connective tissues of the body. These tissues surround, connect, or support the body's structure and organs.

This group of cancers includes those arising from:

Fat (adipose tissue)

Cartilage

Connective tissue (fascia, ligaments, tendons)

Muscle

Skin

Nerves

Joints

Blood vessels

Lymph vessels

The most common sites for soft tissue sarcomas are the arms and legs, but they can also develop in the head and neck, chest, abdomen, and pelvis. While soft tissue sarcomas affect both adults and children, the following information is focused on the condition as it presents in children.

Rhabdomyosarcoma

Rhabdomyosarcoma is the most common form of soft tissue sarcoma found in children. It develops in the muscles that are attached to the skeleton. Each year, approximately 340 children across the nation are diagnosed with rhabdomyosarcoma. This cancer accounts for about 3% of all childhood cancers and 2% of adolescent cancers.

Other Soft Tissue Sarcomas (NRSTS)

Other childhood soft tissue tumours are classified as non-rhabdomyosarcoma soft tissue sarcomas (NRSTS). Collectively, this group makes up approximately 4% of paediatric cancers. Many types exist and are classified according to their tissue of origin. The most common soft tissue sarcomas in children, other than rhabdomyosarcoma, include:

Fat Tissue Tumours (Liposarcoma)

In children, this is typically a low-grade, slow-growing tumour. The most common type is myxoid liposarcoma.

Bone and Cartilage Tumours (Extraskeletal Chondrosarcoma)

This type develops in the cartilage outside of the bone structure, although it is more common in adults.

Connective Tissue Tumours

  • Desmoid Tumours (Aggressive Fibromatosis): These tumours usually grow slowly and are generally unlikely to spread to other parts of the body. Children with the inherited genetic condition familial adenomatous polyposis (FAP) are at an increased risk.
  • Fibrosarcoma: This is often seen in children under four years old, particularly infants. Tumours tend to be large and grow quickly but generally do not spread.

Muscle Tumours (Leiomyosarcoma)

This is associated with the Epstein-Barr virus in children with HIV/AIDS. Survivors of retinoblastoma also have a higher risk.

Skin Tumours (Fibrohistiocytic Tumours)

  • Plexiform Fibrohistiocytic Tumours: These start as a painless mass on or just beneath the skin of the arm, hand, or wrist.
  • Undifferentiated Pleomorphic Sarcoma: This tends to develop in the arms or legs of children who have received prior radiation therapy or have a history of retinoblastoma.

Nerve Tumours (Malignant Peripheral Nerve Sheath Tumours)

These grow in the protective covering of the nerves outside of the brain and spinal cord. Children with the genetic condition neurofibromatosis type 1 (NF1) are at an increased risk.

Tumours of Unknown Origin (Synovial Sarcoma)

These tumours are typically found in the joints of the legs or arms, or in the head, neck, or trunk. Children under 10 with small tumours have the best chance for successful treatment.

Blood Vessel Tumours

  • Angiosarcomas: These grow quickly in lymph or blood vessels.
  • Epithelioid Hemangioendotheliomas: These typically develop in the liver of infants and are usually benign (not cancerous).

Paediatric Soft Tissue Sarcoma Risk Factors

A risk factor is anything that increases a child's likelihood of developing soft tissue sarcoma. These factors include:

Inherited Genetic Conditions:

  • Neurofibromatosis type 1 (NF1)
  • Li-Fraumeni syndrome
  • Inherited retinoblastoma
  • Werner syndrome
  • Familial adenomatous polyposis (FAP)

Viral Infections:

  • HIV/AIDS and Epstein-Barr virus

Age:

Teenagers and infants under 1 year of age are at a higher risk.

Prior Treatment:

Previous radiation therapy.

It is important to remember that the presence of a risk factor does not mean your child will definitely develop the disease. If any of the above conditions are part of your family's medical history, we encourage you to inform your child's doctor, as genetic testing may be suggested.

Childhood Soft Tissue Sarcoma Symptoms

The signs of soft tissue sarcoma can differ greatly depending on the child and the specific disease type. The location of the sarcoma also plays a significant role in the symptoms that appear.

Initial Symptom

The first sign of a soft tissue sarcoma is usually a painless mass or lump. This may be located on an arm, leg, or the trunk of the body.

Later Symptoms

As the sarcoma grows, it may press on adjacent body parts, such as nerves, muscles, blood vessels, and organs. When this occurs, other symptoms may present, including muscle weakness or pain.

Soft tissue sarcomas are rare. If your child exhibits these symptoms, they are most likely caused by a less serious condition. Nevertheless, it is always advisable to consult with a doctor to rule out other health concerns.

Childhood Soft Tissue Sarcoma Diagnosis

Soft tissue sarcomas are complex and can originate in many different parts of the body. This complexity often makes them challenging to diagnose accurately. However, an accurate diagnosis is absolutely critical to successful treatment, as an incorrect diagnosis can be detrimental.

We strongly advise that the initial biopsy, if possible, be carried out at the cancer centre where your child will be treated. It is best to choose a cancer centre that treats a large number of paediatric sarcoma patients and has a specialised team, including dedicated pathologists.

At SSCHRC, we treat more children with soft tissue sarcoma than most hospitals. Our specialist experts possess a remarkable level of skill, which helps them accurately pinpoint the tumour's location and extent. We utilise the latest diagnostic methods and technology to ensure your child receives the most accurate diagnosis possible, which can significantly influence treatment success.

Soft Tissue Sarcoma Diagnostic Tests

If your child presents with symptoms that may suggest a soft tissue sarcoma, the doctor will examine them closely and gather details about their health and medical history, as well as the family's medical history. One or more of the following diagnostic tests may be used to confirm if your child has a soft tissue sarcoma, determine if it has spread, and check if treatment is effective:

1. Biopsy

A biopsy is the only way to be certain of a soft tissue sarcoma diagnosis. This involves removing a small sample of cells from the tumour to be examined under a microscope. Surrounding tissue and lymph nodes may also be biopsied. Imaging tests may be used before or after the biopsy to determine the exact location and extent of the tumour.

The doctor will select one of the following types of biopsy based on the tumour's location:

  • Fine Needle Aspiration (FNA): A very thin needle is guided into the mass and suction is applied to draw out cells. CT scans may be used to help guide the needle. If this test suggests a soft tissue sarcoma, a core biopsy is often performed to remove a larger tissue sample.
  • Core Needle Biopsy: The doctor uses a needle slightly thicker than the one used for FNA to remove a cylindrical sample of tissue.
  • Incisional Biopsy: An incision (cut) is made in the skin, and a small part of the tumour is surgically removed.
  • Excisional Biopsy: An incision is made in the skin, and the entire growth is removed surgically.

2. Imaging Tests

Several imaging tests can be used to help diagnose soft tissue sarcoma, including:

  • CT or CAT (computed axial tomography) scans
  • MRI (magnetic resonance imaging) scans
  • PET (positron emission tomography) scans
  • Chest X-ray
  • Ultrasound

Childhood Soft Tissue Sarcoma Treatment

If your child is diagnosed with a soft tissue sarcoma, the medical team will discuss the best treatment strategies. The plan is always customised and carefully planned, depending on several factors:

  • The location and specific type of sarcoma
  • Whether the cancer has spread (metastasis)
  • Your child's age and overall health

Treatment for soft tissue sarcoma may include one or more of the following therapies.

Surgery

Surgery is the primary treatment for soft tissue sarcoma. If the entire tumour can be successfully removed, the chance of a positive outcome is higher.

Sarcoma surgery, like all complex procedures, is most successful when performed by a specialist with considerable experience in that particular field. Surgeons at SSCHRC are among the most skilled and recognised globally. They are specialised in soft tissue sarcoma treatment and employ the least-invasive and most advanced surgical techniques.

During the operation, the surgeon removes as much of the tumour as possible, along with a margin of surrounding tissue to ensure the maximum removal of cancer cells. Lymph nodes may also be removed.

Your child may receive chemotherapy or radiation therapy either before or after the surgical procedure. A special type of surgery, called limb-sparing surgery, which is often followed by radiation therapy, means that the majority of patients do not require the removal of an arm or leg to treat the sarcoma.

Chemotherapy

Chemotherapy may be administered before surgery to shrink the tumour, making it easier to remove surgically. For certain types of soft tissue sarcoma, or if the cancer has spread, chemotherapy may also be given after surgery. SSCHRC offers a range of current and advanced chemotherapy options.

Radiation Therapy

Advanced radiation therapy techniques and the renowned skill of SSCHRC doctors allow them to target tumours with high precision, delivering the maximum necessary amount of radiation while minimising the impact on healthy cells.

Although radiation therapy is generally not the main treatment for soft tissue sarcoma, it may be used:

  • Before surgery to shrink the tumour.
  • After surgery to eliminate any remaining cancer cells.
  • If the tumour cannot be completely removed by surgery.

SSCHRC provides the most advanced radiation treatments, including:

  • 3D-conformal radiation therapy: Multiple radiation beams are precisely shaped to the exact shape of the tumour.
  • Intensity-modulated radiotherapy (IMRT): Treatment is meticulously tailored to the specific shape of the tumour.

Watchful Waiting

In some instances, the most appropriate approach may be to closely monitor your child for a period of time before initiating treatment.

Targeted Therapies

SSCHRC is actively leading the future of soft tissue sarcoma treatment by developing innovative targeted therapies. These specialised agents are designed to treat a cancer's specific genetic and molecular profile, helping the body to fight the disease.

Many doctors at SSCHRC are dedicated researchers who have pioneered and actively lead national and international clinical trials involving novel targeted agents.

Our Treatment Approach and Specialized Expertise

At SSCHRC, one of the world's foremost teams of experts customises a treatment plan for your child. This multidisciplinary group is among the few in the nation with specialised experience in treating these rare types of cancers.

SSCHRC is committed to providing the most advanced treatments for soft tissue sarcoma with the least impact on your child's body, both today and in the future.

The specialised team that treats your child includes highly trained doctors such as oncologists, surgical oncologists, and radiation oncologists. They are supported by a group of dedicated professionals, including advanced practice nurses, physician assistants, therapists, and social workers.

Since surgery is often the main treatment, and the procedures can be delicate and complex, our surgeons are among the most skilled in the world in soft tissue sarcoma surgery. They employ the latest techniques and technology to give your child the best possible chance for successful treatment.

SSCHRC offers a range of clinical trials for soft tissue sarcomas, keeping us at the forefront of discovering new and better treatment methods, which translates to better chances for successful treatment for your child.

Sri Shankara Cancer Hospital Footer Shankara Cancer Hospital & Research Center