Desmoplastic (des-moe-PLAS-tik) small round cell tumors (DSRCT) are a type of cancer that often begins in the abdomen. Sometimes this type of cancer can occur in other parts of the body.

Desmoplastic small round cell tumors are rare cancers that begin as a growth of cells. The growths often form on the tissue that lines the inside of the abdomen and pelvis. This tissue lining is called the peritoneum. The cancer cells can quickly spread to other nearby organs. This might include the bladder, colon and liver.

Desmoplastic small round cell tumors can happen to anyone, but they're more common in young men and boys.

Treatment for desmoplastic small round cell tumors typically involves a combination of treatments. Options might include surgery, chemotherapy and radiation therapy.

Desmoplastic small round cell tumors are a type of soft tissue sarcoma. Soft tissue sarcoma is a term used to describe a large group of cancers that all start in the tissues that connect, support and surround other body structures.

Symptoms

Desmoplastic small round cell tumor symptoms vary depending on where the cancer begins. Most often it begins in the abdomen.

Signs and symptoms of desmoplastic small round cell tumors in the abdomen include:

• Swelling of the abdomen
• Abdominal pain
• Constipation
• Difficulty urinating

When to see a doctor

Make an appointment with your health care provider if you have any persistent signs and symptoms that worry you.

Causes

It's not clear what causes desmoplastic small round cell tumors.

Doctors know that 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 quickly. This creates a clump of cancer cells called a tumor. The cancer cells can invade and destroy healthy body tissue. In time, the cancer cells can break away and spread to other parts of the body.

Diagnosis

Tests and procedures used to diagnose desmoplastic small round cell tumors include:

• Removing a sample of tissue for testing. Your health care provider might recommend a procedure to remove a sample of cells for testing. This is called a biopsy. The sample might be collected during surgery. Another option might be to get the sample with a needle that's passed through the skin.

  Tissue samples are sent to a lab for testing. Tests can tell your health care team whether cancer is present. Other lab tests analyze the cancer cells to understand which DNA changes are present. The results can help rule out other similar types of cancer and ensure your diagnosis is correct. The results also help your care team pick the treatments that are best for you.

• Imaging tests. Imaging tests help your care team understand the size and location of your cancer. Imaging tests may include ultrasound, CT, MRI and positron emission tomography (PET).

Treatment

Treatment for desmoplastic small round cell tumor depends on your situation. Your health care team considers your cancer's location and whether it has spread to other parts of the body. Most people with this type of cancer receive a combination of treatments.

Surgery

The goal of surgery is to remove all of the cancer. It might not be possible if the cancer has grown into nearby organs. If that happens, your health care provider may recommend chemotherapy with powerful drugs to shrink the cancer first.

When it's not possible to remove the cancer entirely, your surgeon may work to remove as much as possible. Chemotherapy and radiation may be recommended after surgery to kill any cancer cells that might remain.

Chemotherapy

Chemotherapy uses powerful drugs to kill cancer cells. Chemotherapy may be used before surgery to shrink the cancer. This makes it easier to remove with surgery. Chemotherapy may also be used after surgery to kill any cells that might remain after the operation.

Chemotherapy might also be an option for cancer that spreads to other parts of the body. In this situation, chemotherapy may help control symptoms, such as pain.

Chemotherapy options might include:

• Chemotherapy that affects the whole body. Chemotherapy is most often given as a drug that's injected through a vein. The medicine travels throughout your body. The medicine kills quickly growing cells, including cancer cells. It can be used to treat desmoplastic small round cell tumors anywhere in the body.
• Chemotherapy given only to the abdomen. For desmoplastic small round cell tumors in the abdomen, chemotherapy drugs can be given directly to the area around your abdominal organs. This part of the body is called the peritoneal cavity. To give chemotherapy to this area only, the drugs are heated and infused into the abdomen. The drugs are left in place for a set period of time and then removed. This procedure is called hyperthermic intraperitoneal chemotherapy (HIPEC). It might be an option after surgery.

Radiation therapy

Radiation therapy uses powerful beams of energy to kill cancer cells. The energy can come from sources such as X-rays and protons. During radiation therapy, you lie very still on a table and a machine moves around you. The machine directs radiation to precise points on your body.

For desmoplastic small round cell tumors that affect the abdomen, radiation might be an option to kill cancer cells that remain after surgery.

If your cancer has spread to other areas of the body, radiation might be an option to help control signs and symptoms, such as pain.

Targeted drug therapy

Targeted drug treatments attack specific chemicals present within cancer cells. By blocking these chemicals, targeted drug treatments can cause cancer cells to die.

Targeted therapy might be recommended if your cancer comes back after treatment. It may also be offered if your cancer has spread to other parts of the body. Your health care provider may have your cancer cells tested to see if targeted therapy drugs are likely to work against your cancer. Targeted therapy can be used alone or combined with chemotherapy.

Coping and support

Being diagnosed with cancer can feel overwhelming. With time you'll find ways to cope with the distress and uncertainty of cancer. Until then, you may find it helps to:

• Learn enough about cancer to make decisions about your care. Ask your health care provider for details about your cancer. Ask about your treatment options. If you like, ask about your prognosis. As you learn more about desmoplastic small round cell tumors, you may become more confident in making treatment decisions.
• Keep friends and family close. Keep your close relationships strong. They will help you deal with your diagnosis and the impact it has on your life. Friends and family can provide the practical support you'll need. For example, they can help with tasks like taking care of your home if you're in the hospital. They can serve as emotional support when you feel overwhelmed by cancer.

• 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 provider about support groups in your area. Or check with a cancer organization, such as the National Cancer Institute or the American Cancer Society.

Preparing for an appointment

If your health care provider suspects you have a desmoplastic small round cell tumor, you may be referred to a specialist. Often this is a doctor who specializes in treating cancer. This doctor is called an oncologist.

Because appointments can be brief, and there's often a lot to discuss, it's a good idea to arrive prepared. Here's some information to help you get ready.

What you can do

• Write down any symptoms you're experiencing, including any that may seem unrelated to the reason for which you scheduled the appointment.
• Make a list of all medications, vitamins or supplements that you're taking.
• Ask a family member or friend to come with you. Sometimes it can be difficult to remember all the information provided to you during an appointment. Someone who accompanies you may remember something that you missed or forgot.
• Write down questions to ask your health care provider.

Your time with your provider is limited. Prepare a list of questions to help you make the most of your time together. List your questions from most important to least important in case time runs out. For desmoplastic small round cell tumors, some basic questions to ask include:

• Do I have cancer?
• Are there other possible causes for my symptoms?
• What kinds of tests do I need to confirm the diagnosis? Do these tests require any special preparation?
• What stage is the cancer?
• What treatments are available for desmoplastic small round cell tumors, and which do you recommend?
• Can the cancer be removed?
• What types of side effects can I expect from treatment?
• Are there any alternatives to the primary approach that you're suggesting?
• I have other health conditions. How can I best manage these conditions together?
• Are there any dietary or activity restrictions that I need to follow?
• What's my prognosis?
• Are there any brochures or other printed material that I can take with me? What websites do you recommend?
• Should I get additional treatments before or after an operation?
• Is the surgeon you're recommending experienced in this specific type of cancer operation?

What to expect from your doctor

Your provider is likely to ask you a number of questions, such as:

• When did you first notice your signs and symptoms?
• Are you experiencing pain?
• Does anything seem to improve your symptoms?
• What, if anything, appears to worsen your symptoms?

In addition to the questions that you've prepared, don't hesitate to ask other questions.