Undifferentiated pleomorphic sarcoma (UPS) is a rare type of cancer that begins mostly in the soft tissues of the body. Soft tissues connect, support and surround other body structures.
UPS usually occurs in the arms or legs. Less often it can happen in the area behind the abdominal organs (retroperitoneum).
The name undifferentiated pleomorphic sarcoma comes from the way the cancer cells appear under the microscope. Undifferentiated means the cells don't look like the body tissues in which they develop. The cancer is called pleomorphic (plee-o-MOR-fik) because the cells grow in multiple shapes and sizes.
Treatment for UPS depends on the location of the cancer, but often involves surgery, radiation and drug treatments.
UPS used to be called malignant fibrous histiocytoma.
Undifferentiated pleomorphic sarcoma symptoms depend on where the cancer occurs. It most often happens in the arms and legs, but it can happen anywhere in the body.
Signs and symptoms may include:
Make an appointment with a doctor if you develop any persistent signs or symptoms that worry you.
It's not clear what causes undifferentiated pleomorphic sarcoma.
Doctors know this cancer begins when a cell develops changes in its DNA. A cell's DNA contains the instructions that tell a cell what to do. The changes tell the cell to multiply rapidly, creating a mass of abnormal cells (tumor). The cells can invade and destroy nearby healthy tissue. In time, the cancer cells can break away and spread (metastasize) to other parts of the body, such as the lungs and bones.
Factors that may increase the risk of undifferentiated pleomorphic sarcoma include:
Most people who develop undifferentiated pleomorphic sarcoma have no known risk factors, and many people who have risk factors never develop the cancer.
Diagnosis for undifferentiated pleomorphic sarcoma usually starts with a review of your symptoms and a physical examination. This cancer is often diagnosed after other types of cancer have been ruled out.
Tests and procedures may include:
Removing a sample of tissue for testing (biopsy). To make a definitive diagnosis, your doctor collects a sample of the tumor tissue and sends it to a lab for testing. Depending on your particular situation, the tissue sample may be collected with a needle inserted through your skin or during an operation.
In the lab, doctors trained in analyzing body tissues (pathologists) examine the sample to determine the types of cells involved and whether the cells are likely to be aggressive. This information helps rule out other types of cancer and guides your treatment.
Determining the type of biopsy needed and the specifics of how it should be performed requires careful planning by the medical team. Doctors need to perform the biopsy in a way that won't interfere with future surgery to remove the cancer. For this reason, ask your doctor for a referral to a team of experts with extensive experience in treating soft tissue sarcomas before the biopsy.
Treatment for undifferentiated pleomorphic sarcoma usually involves surgery to remove the cancer cells. Other options include radiation therapy and drug treatments (systemic therapies), such as chemotherapy, targeted therapy and immunotherapy. Which treatments are best for you will depend on the size and location of your cancer.
When possible, doctors try to remove the sarcoma completely with surgery. The goal is to remove the cancer and a margin of healthy tissue around it with as minimal an impact as possible.
When the cancer affects the arms and legs, surgeons prefer to use limb-sparing operations. However, in some cases it may be necessary to amputate the affected arm or leg. Other treatments, such as radiation therapy and chemotherapy, might be recommended before surgery to shrink a cancer so that it's easier to remove without amputating the affected limb.
Radiation therapy uses high-powered beams of energy, such as X-rays or protons, to kill cancer cells. Radiation therapy can be given as:
External beam radiation. This type of radiation comes from a machine that moves around you as you lie on a table. The machine directs the radiation to precise points on your body.
Radiation may be used before surgery to shrink a sarcoma and make it easier to remove. It may also be used after surgery to kill any cancer cells that remain.
Chemotherapy is a drug treatment that uses chemicals to kill cancer cells. It can be administered by pill or through a vein (intravenously), or both.
Chemotherapy is most often used to treat undifferentiated pleomorphic sarcoma that comes back after initial treatment or that spreads to other areas of the body.
Sometimes chemotherapy is used before surgery to shrink the cancer so that it's easier to remove during an operation.
Chemotherapy may also be combined with radiation.
Targeted drug treatments focus on specific abnormalities present within cancer cells. By blocking these abnormalities, targeted drug treatments can cause cancer cells to die.
For undifferentiated pleomorphic sarcoma, targeted therapy drugs may be combined with chemotherapy.
Some targeted therapies only work in people whose cancer cells have certain genetic mutations. Your cancer cells may be tested in a laboratory to see if these drugs might help you.
Immunotherapy uses your immune system to fight cancer. Your body's disease-fighting immune system may not attack your cancer because the cancer cells produce proteins that help them hide. Immunotherapy works by interfering with that process.
Immunotherapy treatments are generally reserved for people with advanced cancer.
No alternative treatments have been found helpful in treating undifferentiated pleomorphic sarcoma. But some complementary and alternative treatments may relieve the symptoms you experience due to cancer or cancer treatment.
Alternative treatments that may help relieve symptoms include:
A diagnosis of cancer such as undifferentiated pleomorphic sarcoma can be overwhelming. With time you'll find ways to cope with the distress and uncertainty of cancer. Until then, you may find it helps to:
Find someone to talk with. Find a good listener who is willing to listen to you talk about your hopes and fears. This may be a friend or family member. The concern and understanding of a counselor, medical social worker, clergy member or cancer support group also may be helpful.
Ask your doctor about support groups in your area. Or check your phone book, library or a cancer organization, such as the National Cancer Institute or the American Cancer Society.
If your family doctor suspects you have undifferentiated pleomorphic sarcoma, you'll likely be referred to a cancer doctor (oncologist) who specializes in sarcomas. Undifferentiated pleomorphic sarcoma is rare and often requires complex care. It's best treated by someone who has significant experience with it, which often means an academic or multispecialized cancer center.
Because appointments can be brief, and there's often a lot of information to discuss, it's a good idea to arrive well prepared. Here's some information to help you get ready.
Your time with your doctor is limited, so preparing a list of questions can help you make the most of your time together. List your questions from most important to least important in case time runs out. For undifferentiated pleomorphic sarcoma, some basic questions to ask your doctor include:
Your doctor is likely to ask you a number of questions. Being ready to answer them may make time to cover other points you want to discuss. Your doctor may ask:
In addition to the questions that you've prepared to ask your doctor, don't hesitate to ask other questions.
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