Understanding Solitary Fibrous Tumors (SFT): What You Need to Know

Have you ever felt an unusual lump somewhere on your body and felt a little worried?

Finding something unexpected beneath your skin or feeling an odd pressure inside can certainly cause panic and uncertainty. When unexpected health concerns arise, understanding what is happening helps calm your mind. Today, we are exploring a rare type of growth that you might not hear about very often in everyday conversations. Medical professionals refer to this condition as a solitary fibrous tumor, or SFT for short.

Even though the medical name sounds complex and intimidating, we can break it down into simple, easy-to-understand terms. Whether you or a loved one received this diagnosis, this complete guide explains what an SFT is, where it develops, how doctors diagnose it, and what treatment options are available to keep you healthy and safe.

What Is a Solitary Fibrous Tumor?

To understand this condition, we first need to look at soft tissues. Your body contains soft tissues that connect, support, and surround other body structures. These tissues include your muscles, fat, blood vessels, tendons, and nerves.

A solitary fibrous tumor starts inside these soft tissues. While these growths can develop almost anywhere in your body, they most commonly appear in the pleura. The pleura is the thin, protective lining that surrounds your lungs and helps you breathe smoothly.

The nature of these growths generally falls into two distinct categories:

• Non-cancerous (Benign): These growths develop very slowly and do not spread to other parts of your body.
• Cancerous (Malignant): These growths develop faster and have the potential to invade nearby tissues or spread to distant organs.

Even when a solitary fibrous tumor is non-cancerous, doctors usually recommend having surgery to remove it completely. Taking it out early prevents future complications, pain, or potential growth issues down the road.

Do These Growths Have Other Names?

Yes, medical terminology evolves over time as researchers discover more about diseases. In the past, doctors used a different name for this condition because they believed it only grew inside the chest cavity near the lungs.

Historically, medical books called them "benign fibrous tumors of the pleura." This older name reflected the belief that the growth was always benign and always lived on the lung lining.

Later, advanced medical research proved that these tumors do not just live in the chest. They can develop in your liver, brain, neck, head, and many other areas. Because of these discoveries, the medical community adopted the broader term, solitary fibrous tumor.

SFT and Pleural Mesothelioma: What Is the Difference?

Because both conditions can develop near your lungs, people sometimes confuse an SFT with pleural mesothelioma. However, these two medical issues are completely different.

Let us examine the key differences using the comparison table below.

Who Is at Risk for SFT?

Anyone can technically develop a solitary fibrous tumor, but doctors diagnose most cases in adults between 50 and 60 years old. This condition is exceptionally rare in young children and teenagers.

To put the rarity into perspective, solitary fibrous tumors account for less than 2 out of every 100 soft tissue tumors diagnosed worldwide.

Where Can SFT Grow in Your Body?

While lung linings are the most frequent site, these growths can appear in several surprising locations:

• Connective tissues surrounding your brain and spinal cord.
• Inside your liver.
• Your lungs and the pleural membrane surrounding them.
• The nasal passages and paranasal sinuses.
• Soft tissues inside the eye socket (orbit).
• Your thyroid gland in the neck.

Why Do These Tumors Form? What Is the Cause?

To be completely honest, medical researchers do not yet know the exact trigger that causes a solitary fibrous tumor to start growing.

However, modern scientific studies have uncovered a major clue. Researchers discovered that a specific genetic event often occurs inside the cells of people with an SFT.

Two specific genes inside your cells—known as NAB2 and STAT6—accidentally fuse together. This gene fusion triggers abnormal cell multiplication, causing tissue to multiply rapidly and form a solid tumor mass.

What Are the Symptoms of an SFT?

Solitary fibrous tumors usually grow very slowly over many months or years. Because of this slow growth, nearly half of all people who have an SFT experience zero symptoms at first.

Symptoms typically start when the tumor grows large enough to push against nearby organs, nerves, or bones. The specific signs you notice depend entirely on where the tumor lives in your body.

Here is what different locations might feel like:

How Do Doctors Diagnose This Condition?

When you visit a doctor with unusual symptoms, they investigate your health thoroughly to find the root cause. Depending on where the tumor might live, your doctor will use several tests:

• Physical Examination: Your doctor asks detailed questions about your symptoms, reviews your medical history, and checks your physical health.
• Imaging Scans: Advanced pictures help doctors see the exact size, shape, and location of the growth. These scans include X-rays, CT scans, MRI scans, Ultrasounds, and PET scans.
• Specialized Eye Exams: If the tumor sits near your eye socket, doctors use tests like Optical Coherence Tomography (OCT) to check your vision structures.
• Biopsy: This is the clear diagnostic test. A doctor takes a tiny sample of tissue from the growth and sends it to a pathology lab. Examining cells under a microscope provides a 100% accurate diagnosis of the tumor type.

Classification and Grading of SFT Severity

The World Health Organization (WHO) classifies solitary fibrous tumors into different grades based on how aggressive the cells look and how fast they grow:

• Grade I (Low-Grade): These are the least aggressive tumors. The cells look very similar to normal tissue and grow at a very slow pace.
• Grade II (Intermediate-Grade): These cells look slightly abnormal and grow a bit faster than Grade I tumors. They carry a higher chance of turning cancerous.
• Grade III (High-Grade): These are aggressive tumors with highly abnormal cells. They grow quickly and carry a greater risk of coming back or spreading to other body parts.

What Are the Treatment Options?

The primary and most successful treatment for a solitary fibrous tumor is surgery. An experienced surgeon works to remove the entire tumor along with a safe margin of healthy surrounding tissue.

Sometimes, the tumor's location makes surgery difficult, or the growth is extremely large. In those situations, your medical team may recommend additional therapy:

• Radiation Therapy: High-energy beams destroy tumor cells or shrink them down. Doctors sometimes use radiation before surgery to make large tumors easier to remove safely.

Possible Complications of SFT

Hearing that you have a tumor naturally brings worries about cancer or spreading (metastasis). Having a surgeon remove the growth successfully lowers these risks greatly.

Depending on where the tumor grew, other complications can occur if it pressed on vital structures:

• Paralysis: This happens if a tumor grows near your spinal cord and damages nerve pathways.
• Pleural Effusion: Fluid builds up inside your chest cavity around your lungs.
• Optic Atrophy: Damage occurs to the nerve connecting your eye to your brain.

What Is the Recovery Outlook After Treatment?

Most people recover very well after a surgeon successfully removes a solitary fibrous tumor. Because of the small risk that the growth could return later, your doctor will schedule regular follow-up visits.

Your doctor will use periodic imaging scans at set time intervals to check your body and make sure the tumor has not come back. Sticking to this follow-up schedule is one of the best ways to protect your long-term health.