Treatment of Soft Tissue Sarcoma

Sarcoma is a malignant, or cancerous tumour that arises from connective tissue, such as bones, fat, cartilage and muscles. In general, sarcoma treatment may include chemotherapy, radiation therapy and surgery. The best chance to cure a soft tissue sarcoma is to remove it with surgery, so surgery is part of the treatment for all soft tissue sarcomas whenever possible. Your surgeon and other doctors must be experienced in the treatment of sarcomas. These tumours are hard to treat and require both experience and expertise. Studies have shown that patients with sarcomas have better outcomes when they're treated at specialized cancer centres that have experience in sarcoma treatment.

1. Surgery for soft tissue sarcomas:

Depending on the site and size of a sarcoma, surgery might be able to remove cancer. The goal of surgery is to remove the entire tumour along with at least 1 to 2 cm (less than an inch) of the normal tissue around it. This is to make sure that no cancer cells are left behind. When the removed tissue is looked at under a microscope, the doctor will check to see if cancer is growing in the edges (margins) of the specimen.

• If cancer cells are found at the edges of the removed tissue, it is said to have positive margins. This means that cancer cells may have been left behind. When cancer cells are left after surgery, more treatment? such as radiation or another surgery -- might be needed.
• If cancer isnt growing into the edges of the tissue removed, it's said to have negative or clear margins. The sarcoma has much less chance of coming back after surgery.

In the past, many sarcomas in the arms and legs were treated by removing the limb (amputation). Today, this is rarely needed. Instead, the standard is surgery to remove the tumour without amputation. This is called limb-sparing surgery. A tissue graft or an implant may be used to replace the removed tissue. This might be followed by radiation therapy.

If the sarcoma has spread to distant sites (like the lungs or other organs), all of the cancer will be removed if possible. If it isn't possible to remove all of the sarcomas, then surgery may not be done at all. Most of the time, surgery alone cannot cure a sarcoma once it has spread. But if it has only spread to a few spots in the lung, the metastatic tumours can sometimes be removed. This can cure patients, or at least lead to long-term survival.

2. Radiation therapy for soft tissue sarcomas:

Radiation therapy uses high-energy rays (such as X-rays) or particles to kill cancer cells. It's a key part of soft tissue sarcoma treatment. Most of the time radiation is given after surgery. This is called adjuvant treatment. It's done to kill any cancer cells that may be left behind after surgery. Radiation can affect wound healing, so it may not be started until a month or so after surgery. Radiation may also be used before surgery to shrink the tumour and make it easier to remove. This is called neoadjuvant treatment. Radiation can be the main treatment for sarcoma in someone who isn't healthy enough to have surgery. Radiation therapy can also be used to help ease symptoms of sarcoma when it has spread. This is called palliative treatment.

Types of radiation therapy

• External beam radiation: This is the type of radiation therapy most often used to treat sarcomas. Treatments are often given daily, 5 days a week, usually for several weeks. This better focuses the radiation on the cancer and lessens the damage to healthy tissue.
• Proton beam radiation: This uses streams of protons instead of x-ray beams to treat the cancer. It hasn't been proven to be a better treatment for soft tissue sarcoma. Proton beam therapy is not widely available.
• Intraoperative radiation therapy (IORT): For this treatment, one large dose of radiation is given in the operating room after the tumour is removed but before the wound is closed. It also allows nearby healthy areas to be shielded more easily from the radiation. IORT is only one part of radiation therapy, and the patient gets some other type of radiation after surgery.
• Brachytherapy: Sometimes called internal radiation therapy, is a treatment that places small pellets (or seeds) of radioactive material in or near the cancer. For soft tissue sarcoma, these pellets are put into catheters (very thin, soft tubes) that have been placed during surgery. Brachytherapy may be the only form of radiation therapy used or it can be combined with external beam radiation.

Side effects of radiation treatment

• Skin changes where the radiation goes through the skin, which can range from redness to blistering and peeling
• Fatigue
• Nausea and vomiting
• Diarrhea Pain with swallowingLung damage leading to problems breathing Bone weakness, which can lead to fractures or breaks years later
• Radiation of large areas of an arm or leg can cause swelling, pain, and weakness in that limb.
• If given before surgery, radiation may cause problems with wound healing.
• If given after surgery, it can cause long-term stiffness and swelling that can affect how well the limb works.

3. Chemotherapy for soft tissue sarcomas:

Chemotherapy is the use of drugs given into a vein or taken by mouth to treat cancer. These drugs enter the bloodstream and reach all areas of the body, making this treatment useful for cancer that has spread to other organs. Depending on the type and stage of sarcoma, chemotherapy may be given as the main treatment or as an adjuvant to surgery. Different types of sarcoma respond better to chemo than others and also respond to different types of chemo. Chemotherapy for soft tissue sarcoma generally uses a combination of several anti-cancer drugs.

The most commonly used drugs are ifosfamide and doxorubicin. When ifosfamide is used, the drug mesna is also given. Mesna is not a chemo drug. It's used to protect the bladder from the toxic effects of ifosfamide.

• Isolated limb perfusion (ILP) is a different way to give chemo. The circulation of the limb (arm or leg) with the tumour in it is separated from that of the rest of the body. Chemo is then given just to that limb. Sometimes the blood is warmed up a bit to help the chemo work better (this is called hyperthermia). ILP may be used to treat tumours that cannot be removed or to treat high-grade tumours before surgery. It can help shrink tumours.

Side effects depend on the type of drugs, the amount taken, and the length of treatment. Most side effects go away over time once treatment is stopped. Common chemo side effects include:

• Nausea and vomiting
• Loss of appetite
• Loss of hair
• Mouth sores
• Fatigue
• Low blood count

4. Targeted drug therapy for Soft tissue sarcomas:

Targeted therapy drugs attack parts of cancer cells that make them different from normal, healthy cells. These drugs work differently from standard chemotherapy drugs, and they often have different. Each type of targeted therapy works differently, but all of them affect the way a cancer cell grows, divides, repairs itself, or interacts with other cells. Targeted therapy is becoming an important treatment option for some of these cancers.

Many other targeted drugs are now being used to treat other types of cancer, and some of these might also help treat certain types of soft tissue sarcomas. Examples of these drugs include:

• Regorafenib (Stivarga)
• Sorafenib (Nexavar)
• Sunitinib (Sutent)

5. Treatment of Soft Tissue Sarcomas, by Stage

• Stage I soft tissue sarcoma- Stage I soft tissue sarcomas are low-grade tumours of any size. Small (less than 5 cm or about 2 inches across) tumours of the arms or legs may be treated with surgery only. If the tumour is not in a limb, (for example it's in the head, neck, or abdomen), it can be harder to take out the entire tumour with enough normal tissue around it. For these tumours, radiation with or without chemo may be given before surgery. This may be able to shrink the tumour enough to remove it entirely with surgery.

• Stages II and III soft tissue sarcoma- Most stage II and III sarcomas are high-grade tumours. They tend to grow and spread quickly. Some stage III tumours have already spread to nearby lymph nodes. These tumours also tend to grow back in the same area after they're removed. This is called local recurrence. For all stage II and III sarcomas, removing the tumour with surgery is the main treatment. If the tumour is large or in a place that would make surgery difficult, but not in lymph nodes, the patient may be treated with chemo, radiation, or both before surgery. These treatments lower the chance of the tumour coming back in or near the same place it started.
• Stage IV soft tissue sarcoma- A sarcoma is considered stage IV when it has spread to distant parts of the body. Stage IV sarcomas are rarely curable. However, some patients may be cured if the primary tumour and all of the areas of cancer spread can be removed by surgery. For people whose primary tumours and all metastases cannot be completely removed by surgery, radiation therapy and/or chemotherapy are often used to relieve symptoms.