Soft Tissue Sarcoma: Specialists and Information

Cancer occurs when the body’s own tissue undergoes changes and then begins to grow uncontrollably.

Soft tissue sarcomas are classified into different subtypes based on their tissue of origin.

The common liposarcoma (10 percent of cases) develops from fat cells. The tumor cells exhibit histological characteristics of fat cells. The more similar the cancer cells are to the tissue of origin, the less aggressive they are.

Liposarcoma is a slow-growing, painless tumor that is usually found in the extremities @ timonina /AdobeStock

In total, there are over 50 different types of soft tissue sarcomas. With about one to two cases per 100,000 people annually, soft tissue sarcomas are very rare tumors in adults. The peak incidence in adults occurs between the ages of 45 and 55.

In children and adolescents, soft tissue tumors are the fourth most common group of solid tumors. Most children are under 15 years of age when they develop a soft tissue sarcoma.

The symptoms and their severity depend heavily on the location and extent of the soft tissue sarcoma. Some soft tissue sarcomas—particularly those of the lower extremities—are initially noticeable as painless swelling.

In approximately 60 percent of cases, a soft tissue sarcoma is located in the upper extremities (arms and legs). Forty percent of soft tissue sarcomas develop in the lower extremities.

Soft tissue sarcomas occur less frequently in the following areas:

• the trunk
• the abdominal cavity, or
• in the head and neck region

Depending on its location and size, the tumor can impair the function of neighboring structures. For example, tumors near a joint can lead to restricted joint movement.

Tumors in the urinary and reproductive systems can cause:

• Abdominal pain
• Blood in the urine
• Painful urination
• Constipation and/or
• Swelling of the testicles

Less commonly, however, general symptoms may appear, such as:

• Decreased energy
• Fatigue
• Exhaustion or
• weight loss

In about one in ten patients, the tumor has already metastasized (spread) by the time of diagnosis. Soft tissue sarcomas often spread to the lungs and cause symptoms such as a dry cough and shortness of breath, especially during physical exertion.

The development and causes of soft tissue sarcomas remain largely unclear today.

A genetic component has so far been identified in only a very small proportion of soft tissue sarcomas. People with Recklinghausen’s disease therefore have a significantly increased risk of developing a malignant tumor of the nerve sheath tissue. Recklinghausen’s disease is a hereditary form of neurofibromatosis type 1 and can cause nerve tumors.

Certain chemicals can also increase the risk of soft tissue sarcoma, particularly when combined with prior radiation therapy.

These dangerous chemicals include:

• the thermoplastic polyvinyl chloride (PVC)
• asbestos fibers, and
• arsenic

Asbestos fibers increase the risk of developing soft tissue sarcoma @ ALEXEY /AdobeStock

Finally, as with all types of cancer, the risk of developing soft tissue sarcoma also increases with age.

Treatment for soft tissue sarcomas is less standardized than for other types of tumors. The optimal strategy is currently still the subject of research.

The following specialists should be involved in planning treatment:

• Surgery
• Radiation Oncology, and
• Medical Oncology (Tumor Medicine)

Treatment for soft tissue sarcoma aims to surgically remove the tumor (resection of the primary tumor) and its metastases. 

The surgical technique and strategy depend on:

• Size
• location, and
• Growth behavior of the sarcoma
• Surgery on the primary tumor

Most soft tissue sarcomas remain confined to the body’s natural anatomical boundaries for an extended period. Therefore, doctors often remove the tumor along with all the tissue in the affected area of the body. This includes the surrounding tissue compartment. This procedure is therefore referred to as a compartment resection.

This procedure is not always possible for tumors in the head and neck region or on the trunk due to their unfavorable location and extent. As an alternative, doctors often remove the sarcoma along with a margin of healthy tissue. 

This is followed by radiation therapy to the affected regions to kill any remaining tumor cells (adjuvant radiation therapy).

For patients with locally confined tumors in early stages, surgical removal of the tumor is sufficient in many cases.

In cases of extensive spread and the presence of metastases, additional chemotherapy and/or radiation therapy is usually required.

• Neoadjuvant therapy to reduce the size of the sarcoma

In most cases, metastases from soft tissue sarcomas are limited to the lungs. This is particularly true in the early stages of the disease.

As the cancer progresses, metastases may also occur outside the lungs. In these cases, systemic chemotherapy is recommended as first-line therapy. 

It is administered before surgery. Doctors refer to this as neoadjuvant therapy. Even if the tumor can only be removed through amputation, neoadjuvant therapy can be helpful.

The goal is to shrink the sarcoma enough so that doctors can remove it completely without amputating the affected limb. 

The following methods are available to reduce the size of the tumor:

• Systemic chemotherapy with or without additional heating of the tumor cells (hyperthermia)
• Radiation therapy or
• Isolated hyperthermic limb perfusion (ILP)

Isolated hyperthermic limb perfusion results in limb preservation in approximately 80 percent of cases. This does not worsen the overall prognosis.

First, physicians surgically isolate the circulation of the affected limb from the rest of the body’s circulatory system. A heart-lung machine takes over the heart’s function during this procedure.

They then administer anticancer drugs (cytostatics) into this isolated circulatory system to kill the tumor cells. In most cases, the anticancer drug melphalan is used in perfusion therapy.

This helps prevent serious systemic (affecting the entire body) side effects.

In addition, doctors heat the tissue of the limb to enhance the effect of the anticancer drugs.

Treatment for soft tissue sarcoma includes surgery, radiation therapy, and chemotherapy @ Seventyfour /AdobeStock

• Reconstructive Surgery

In some cases, doctors must remove such large areas of tissue that reconstructive surgery is necessary. This surgery serves to compensate for large tissue defects and restore the functionality of the affected body part as much as possible.

Reconstructive surgery can be performed immediately following the removal of the sarcoma. If further treatments such as chemotherapy or radiation therapy are planned after the surgery, the reconstructive surgery is performed afterward.

In this way, doctors move or transplant the body’s own tissue, such as muscle flaps, to cover skin and soft tissue defects. 

Specialists are now able to transplant the following structures to compensate for tissue loss:

• Skin
• Muscle
• Limb segments and
• even some nerve tissue

Doctors can also correct potential bone defects using what are known as endoprostheses. Endoprostheses are implants that replace natural structures in the body.