Pigmented Villonodular Synovitis


Pigmented villonodular synovitis (PVNS) is a type of tumor that leads to the thickening of the synovium. It is the slim layer of tissue that lines the tendons and joints.


The overgrowth or mass or tumor that forms in this tumor is benign, that is noncancerous. Therefore, it doesn’t spread to other parts of the body. However, this cancer progresses with time.


It can become and cause more bone damage and arthritis. Pigmented Villonodular Synovitis mostly affects the knees. However, it can attack other joints as well. In many cases, treatment is performed by removing the tumor mass and joint lining.


PVNS is usually of 2 types-localized and diffuse. Localized PVNS is one that affects the tendons. The tumor affects the tendons that support the joint or occurs in just a single portion of the joint. This form of PVNS usually reacts well to the treatment.


Another type is diffuse in which the tumor involves the whole joint and thus cancer becomes more widespread. This tumor is difficult to treat as it becomes highly aggressive.


What causes PVNS?


There is no exact cause for Pigmented villonodular synovitis (PVNS). However, some researchers figure out that certain genetic changes have a link with PVNS. But despite that, the link to genetic factors is not clear yet.


Furthermore, in some patients suffering from PVNS, a defect is usually present in the cells lining the diseased joint. These small number of defective cells produce a protein called colony-stimulating factor 1 receptor (CSF-1R). As per the researchers, this protein has involvement in PVNS.





If the tumor is of localized type, then it causes swelling and pain in that particular area. Moreover, significant swelling may be present. There are other symptoms also which include catching, instability, and locking in the joint.


However, in diffuse PVNS, symptoms arise gradually. I may start with stiffness, swelling, and joint pain. Sometimes, hemarthrosis may be present, which is a condition where blood accumulates in the joint space.


Even no or minimal trauma can lead to this condition. Furthermore, in both types, symptoms may start and end over time.


Doctor Examination.


To diagnose pigmented villonodular synovitis (PVNS), a doctor will do a thorough physical examination to look for physical signs of the tumor. Then, he/she will perform several symptoms which include;


X-rays. This test gives clear images of the dense structure like bones. If there is no damage to the bone, then a PVNS may not exist on an x-ray. However, to rule out other reasons for the pain, your doctor may use X-rPVNS


Magnetic resonance imaging (MRI) scan. An MRI is helpful in the diagnosis of a PVNS as it provides images of the soft tissues in the body. An MRI shows a nodular mass in case of a localized PVNS.


However, an extensive thickening of the lining of the joint, or an extensive mass may be present in a diffuse PVNS. This occurs because of damage to the cartilage or other destructive bone changes.


Joint aspiration. In this method, your doctor will remove fluid from your joints using a syringe. Then, he/she will analyze it.  Furthermore, bloody joint fluid is present in many cases of PVNS.


Biopsy. To confirm the diagnosis of PVNS, a biopsy becomes necessary. In this procedure, your surgeon removes a small amount of affected tissue and analyzed it under a microscope. Therefore, a small operation is necessary to remove the tissue. Before a biopsy, your doctor gives you local anesthesia.



Surgery is the main treatment for PVNS as it grows to a large size and destroys healthy bone. Thus, your surgeon will try to remove the damaged parts of the joint lining. Your surgeon will try to repair the tendon if a tumor affects this too.

Surgical Procedures. 



In this procedure, your surgeon will make small incisions around the affected joint. He/she will then insert an arthroscope, which is a small camera. With the help of this camera, your doctor can see images inside the tumor. Thus, he/she can guide small surgical instruments to tumor location.


Open surgery.

To reduce the chances of PVNS recurrence, your doctor may remove the entire joint lining. You may require this when the tumor affects both the front and back of the knee.


In open surgery, your doctor makes a single large excision which gives your surgeon full access to the area. Then, he/she removes the entire mass of the tumor.


Combined arthroscopic and open surgery.

In this procedure, both methods become helpful. Open surgery helps to remove the tumor mass at the back of the knee. While an arthroscopic procedure to remove the anterior joint lining of the front knee. This way an easier recovery becomes possible.


Total joint replacement.

A diffuse PVNS can lead to the great destruction of joints. When the tumor completely damages a joint, the best option to improve function and relieve the pain is a total joint replacement.


In this procedure, your doctor removes a damaged joint and replaces it with plastic, metal, or certain ceramic parts. However, in a few cases, a tumor may return even after the joint replacement.



Your doctor may use radiation therapy to shrink tumors and for the treatment of diffuse PVNS. In case the surgery is not successful, the remaining tumor cells can be killed by using radiations.

Unlike earlier times when your technician used to give you radiation externally, these days things are different. Your healthcare provider may order a newer procedure called intra-articular radiation.

Here, your doctor will inject the radioactive fluid into your body with a needle. This improves some complications of the tumor.


Drug therapy.

For the treatment of PVNS, certain medications may be helpful. Joint cells produce a protein called CSF-1R protein. The medications work against these cells. However, your doctor will look if you are a fit candidate for this therapy.


Coping and support 


When you get diagnosed with Pigmented villonodular synovitis (PVNS), it could be frightening for you. The condition will be no different for your family.


However, you may learn to cope with the uncertainty and distress related to cancer with time.  Thus, you need to follow these instructions until then;


Call on for medical support:


Various things are going to help you. For instance, the knowledge and understanding of a medical social worker, or any other mental health professional is necessary. They will help you in understanding your cancer.


Furthermore, if your child or other family member suffers from cancer, you need to ask health care professionals for advice. They will provide you with options for medical health support. This will also provide you with emotional and social support.


In addition to this, you can check various online services that will provide you support to combat cancer.


  • Gain more knowledge about Pigmented villonodular synovitis (PVNS) to make decisionsabout control and care: 


Ask your doctor about various treatment options related to Pigmented villonodular synovitis (PVNS). Little knowledge is dangerous. Therefore, more confidence in understanding and making decisions about treatment options will be there with you. So you should always learn more about the disease.


Ask the health care team for guidance if your child has cancer. Therefore, get more and more information for appropriately caring for the patient.


Be close to your friends and family:

A close and strong relationship with your family and friends is necessary. It will help you deal with Pigmented villonodular synovitis (PVNS).


You need practical support, moral support from your friends and relatives. Thus, someone should be there for you to look after the family. Emotional support from them is going to matter most. Thus, a healthy and happy person will ultimately efficiently fight the disease.


Prepare for your appointment


You are likely to start making an appointment with your primary care doctor if some signs and symptoms worry you. Ask for a referral to an experienced specialist if your doctor suspects Pigmented villonodular synovitis (PVNS).


A team of specialists typically can treat. For instance;

Tumor surgeons who have specialization in operating bone tissue cancers.

Doctors who have a specialization in treating cancers with systemic medications or chemotherapy.

Pathologists diagnose the specific type of cancer by analyzing a tissue.

Rehabilitation specialists who after surgery help in the recovery of a tumor.


What you should expect from your doctor:


You will face several questions from your doctor. Thus, you should be ready to answer these. So, give more time to your doctor to address them. Your doctor may ask;


What signs and symptoms concern you more?


Have your symptoms been occasional or continuous?


When did you start to notice the symptoms?

The severity of your symptoms?


Is there anything that improves your symptoms?


Is there anything that worsens your symptoms?


Do you have any family or personal history of cancer?