Fibrosarcoma: Causes, Symptoms, and Treatment
Medically reviewed by Achuta Uppu, MD, Internal Medicine. Last reviewed: October 23, 2026.
What kind of doctor treats Fibrosarcoma?
An oncologist (a cancer doctor) usually treats fibrosarcoma, often with a surgeon who has experience with sarcomas (cancers of the soft tissues or bone). People with sarcomas tend to have better outcomes when they are treated at specialized cancer centers. A direct primary care or concierge doctor can be a first stop for an evaluation and can refer you to a specialist when needed.
What is fibrosarcoma?
Fibrosarcoma is a sarcoma, a cancer of the soft tissues, such as fibrous tissue. Sarcomas are an uncommon type of cancer that start from bone or soft tissues, like muscle, fat, nerves, fibrous tissue, or blood vessels.
Adult fibrosarcoma usually starts in the fibrous (connective) tissue of the legs, arms, or trunk.
Infantile fibrosarcoma is a different, usually less aggressive type.
Symptoms
About half of soft tissue sarcomas start in an arm or leg. Most people notice a lump that has grown over a few weeks or months. The lump may or may not hurt.
About 4 of 10 sarcomas begin in the abdomen (belly). Tumors in the back of the belly can cause blockages or bleeding in the stomach or bowels. They can press on nerves, blood vessels, or nearby organs. They can grow large enough to be felt in the belly. Sometimes they cause pain.
Causes and who gets it
Adult fibrosarcoma is most common in adults between the ages of 20 and 60, but it can occur in people of any age, even in infants. Infantile fibrosarcoma is the most common soft tissue sarcoma in children under 1 year of age.
Some changes in soft tissues are caused by inflammation or injury and can form a mass that looks like a soft tissue tumor. Any new lump still needs to be checked by a doctor.
How doctors diagnose it
If a soft tissue sarcoma is suspected, exams, tests, and a biopsy (a sample of cells) are needed to confirm the diagnosis.
If cancer is found, further tests will be done to learn more about the cancer to help guide treatment.
Treatment
Surgery is often used when possible. The goal of surgery is to remove the tumor with some of the normal tissue around it.
If cancer cells are found at the edges of the removed tissue, some cancer may have been left behind. The best option is often more surgery. Radiation after surgery is another option, and it lowers the chance of the cancer coming back.
For stage II and III sarcomas, treatment can involve both radiation and surgery. Radiation is often given before surgery.
If a tumor is large or hard to remove, chemotherapy (chemo), radiation, or both may be given before surgery. If the tumor and all the spread cannot be removed by surgery, radiation or chemo are often used. For some types, targeted therapy or immunotherapy drugs might also be an option.
When to see a doctor
See a doctor right away if you have a new lump or a lump that is growing anywhere on your body. Also get checked right away for belly pain that is getting worse. Do the same for blood in your stool or black, tarry stools.
These symptoms are more often caused by other things, but they still need to be checked.
Call 911 or go to the emergency room if you have bleeding that will not stop, vomiting blood, or severe belly pain.
How a direct primary care or concierge doctor fits in
A direct primary care doctor charges a flat monthly fee instead of billing insurance, while a concierge doctor usually charges more and often works alongside insurance. A direct primary care doctor can look at a new lump, order first tests, and refer you quickly to a sarcoma team. They can also help keep your care organized during and after treatment.
Common questions
Is fibrosarcoma cancer?
Yes, fibrosarcoma is a cancer. It is a type of sarcoma. Adult fibrosarcoma starts in fibrous tissue, which is connective tissue.
Does a fibrosarcoma lump hurt?
It may or may not. Most people notice a lump that grows over a few weeks or months.
Can an injury make a lump that looks like a tumor?
Yes, some changes in soft tissues are caused by inflammation or injury and can form a mass that looks like a soft tissue tumor. Any new lump still needs to be checked by a doctor.
Is infantile fibrosarcoma the same as adult fibrosarcoma?
No, infantile fibrosarcoma is a different, usually less aggressive type. It is the most common soft tissue sarcoma in children under 1 year of age.
Can fibrosarcoma be cured?
It depends on the stage, which describes how much cancer is in the body. Stage IV sarcomas, which have spread to distant parts of the body, are rarely curable. Some people might be cured if the main tumor and all the spread can be removed by surgery.
Sources
- American Cancer Society - Soft Tissue Sarcomas
- American Cancer Society - Early Detection, Diagnosis, and Staging of Soft Tissue Sarcomas
- American Cancer Society - Treating Soft Tissue Sarcomas
Medical Disclaimer
This content is for general educational and informational purposes only and is not medical advice. It is not a substitute for professional medical advice, diagnosis, or treatment, and reading it does not create a doctor-patient relationship. Always seek the advice of your physician or another qualified health provider with any questions about a medical condition, and never disregard or delay seeking professional advice because of something you read here. If you think you may have a medical emergency, call 911 (or your local emergency number) immediately.
