What are the other Names for this Condition? (Also known as/Synonyms)

• Common Localized Type of GCTTS
• Localized Nodular Tenosynovitis
• Tenosynovial Giant Cell Tumour, Localized Type

What is Localized Type Tenosynovial Giant Cell Tumor? (Definition/Background Information)

• Giant cell tumors of tendon sheath (GCTTS) comprises of a group of tumors that develops in the synovial membrane of the joints, joint fluid sac (bursae), and tendon sheath. The tumor consists of many types of polygonal cells in a bed of collagen
• They are classified according to their behavior and site of occurrence. Tumors may arise within the joint (intra-articular tumors) or outside the joint (extra-articular tumors). The growth pattern is either localized or diffuse and accordingly there are 2 subtypes of GCTTS:
  • Tenosynovial Giant Cell Tumor, Localized Type
  • Tenosynovial Giant Cell Tumor, Diffuse Type
• Localized Type Tenosynovial Giant Cell Tumor (or Localized Type TSGCT) is a benign soft tissue tumor that typically affects the fingers and toes. It is the most common and milder form of GCTTS. The tumor is generally seen in middle-aged adults
• The Localized Type Tenosynovial Giant Cell Tumor is slow-growing and painless. It is believed to develop due to genetic abnormalities in the presence of certain contributory factors
• Surgical excision of Localized Type of Tenosynovial Giant Cell Tumor with its entire removal, followed by radiation therapy, remains the standard treatment mode
• The prognosis of the tumor is typically excellent following its removal. However, it is potentially known to recur, and hence, multiple surgeries may be required

Who gets Localized Type Tenosynovial Giant Cell Tumor? (Age and Sex Distribution)

• Localized Type of Tenosynovial Giant Cell Tumor usually affects young and middle-aged adults (between 30-50 years of age)
• Children below 10 years and elderly individuals above 60 years are hardly affected
• There is a slight female predominance (female-male ratio 2:1)
• No ethnic or racial preference is seen

What are the Risk Factors for Localized Type Tenosynovial Giant Cell Tumor? (Predisposing Factors)

Currently, no clear risk factors have been established. Nevertheless, the following are thought to be associated with Localized Type Tenosynovial Giant Cell Tumor in some manner:

• Degenerative disorders of the joints; particularly affecting the fingers
• Rheumatoid arthritis
• History of trauma is believed to be a risk factor according to various reports: In some studies, trauma was seen in as few as 5% of the cases; while in other studies, trauma was associated with the condition in up to 50% of the cases

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases one’s chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of Localized Type Tenosynovial Giant Cell Tumor? (Etiology)

The cause of formation of Localized Type Tenosynovial Giant Cell Tumor is due to genetic mutations or genetic abnormalities.

• Chromosomal translocation involving chromosome 1 and the CSF1 gene, is observed in many cases
• This translocation is also known to involve the COL6A3 gene on chromosome 2
• Many tumors show a fusion of an unidentified gene with CSF1 gene
• X-chromosome inactivation is noted

Factors related to formation of Localized Type of TSGCT:

• Initially, from animal model studies, researchers believed that past trauma played a contributory role and that Localized TSGCT occurred secondary to trauma, as an inflammatory reactive process
• Now, researchers believe that the cause is a neoplastic (abnormal tissue growth) process, seen because of chromosomal alterations and changes in the number of cell chromosomes (aneuploidy), in some cases; the tumors are known to grow sporadically and independently

Some of the other theories proposed to explain Localized Type Tenosynovial Giant Cell Tumor development relate to:

• Metabolic defects
• Infections
• Abnormal body immunity
• Blood vessel anomalies

Both, diffuse type and localized type, have the same origin and cause mechanism, but different behavior and presentation.

What are the Signs and Symptoms of Localized Type Tenosynovial Giant Cell Tumor?

The signs and symptoms of Localized Type Tenosynovial Giant Cell Tumor may include the following:

• The presentations are based on the location of the tumor
• The thumb, index, and middle finger of right hand are more commonly affected
• Most of the cases are seen involving the hand, of which 85% tumors are seen in the fingers, near the joints. Other locations include the wrist and elbow (rare)
• In the legs - the knee, ankle, and rarely, the hip is involved
• A painless lump is seen in the affected region; no skin color change is noticed
• The tumors grow slowly over many years
• Most tumors belong to the localized type - the size varies from 5 mm to 4 cm
• In rare cases, bone erosion or skin involvement is seen; but, tumor necrosis is usually not seen
• Larger joints may present larger-sized tumors
• Impaired joint function or restricted joint movement

It may be difficult to distinguish between localized and diffuse tumor forms in the knee joint.

How is Localized Type Tenosynovial Giant Cell Tumor Diagnosed?

A diagnosis of Localized Type Tenosynovial Giant Cell Tumor may involve:

• Physical exam with evaluation of medical history
• Imaging studies including plain X-ray and ultrasound scan of the affected hand or leg
• CT or CAT scan with contrast of the affected region may show a well-defined mass. This radiological procedure creates detailed 3-dimensional images of structures inside the scanned region
• MRI scan of the affected region: A magnetic field is used to create high-quality pictures of certain parts of the body, such as tissues, muscles, nerves, and bones. These high-quality pictures may reveal the presence of the tumor
• A tissue biopsy of the tumor is performed and sent to a laboratory for a pathological examination. A pathologist examines the biopsy under a microscope. After putting together clinical findings, special studies on tissues (if needed) and with microscope findings, the pathologist arrives at a definitive diagnosis. Examination of the biopsy under a microscope by a pathologist is considered to be gold standard in arriving at a conclusive diagnosis
• A differential diagnosis to eliminate other tumor types is considered, before arriving at a definitive diagnosis

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of Localized Type Tenosynovial Giant Cell Tumor?

Complications of Localized Type Tenosynovial Giant Cell Tumor may include:

• Complications are dependent on the site and size of the tumor. In some cases, the tumor may infiltrate into the adjoining tissues and muscles
• The mobility of the joints may be constrained leading to difficulty in walking, folding hands, etc., thereby affecting the quality of life
• Damage of the fingers, knee, elbow, or even other organs, vital nerves, and blood vessels, during surgery
• The tumor recurrence rate, following its surgical excision and removal, varies from 4-30%. Often, multiple surgeries may be required to completely eliminate the tumor

How is Localized Type Tenosynovial Giant Cell Tumor Treated?

The treatment measures for Localized Type Tenosynovial Giant Cell Tumor include the following:

• Surgical excision and removal of the entire lesion, followed by radiation therapy, remains the standard treatment mode. If the tumor is not fully removed, it may recur
• When it is unsafe to surgically remove the lesion due to possibility of severe damage to the joint or weak health condition of the individual, non-invasive procedures (such as radiotherapy) may be adopted
• In some cases, skin grafting and tendon reconstruction may be required
• Post-operative care is important: A minimum activity level is ensured, until the surgical wound heals
• Follow-up care with regular screening and check-ups are important

How can Localized Type Tenosynovial Giant Cell Tumor be Prevented?

• Current medical research has not established a method of preventing Localized Type Tenosynovial Giant Cell Tumor
• Regular medical screening at periodic intervals with blood tests, scans, and physical examinations, are mandatory for those who have already endured the tumor, due to possibility of its recurrence

What is the Prognosis of Localized Type Tenosynovial Giant Cell Tumor? (Outcomes/Resolutions)

• The prognosis of Localized Type Tenosynovial Giant Cell Tumor is excellent with surgical intervention and complete removal of the tumor
• Bone or joint destruction is not generally noted following tumor reappearance, but multiple surgeries may be necessary to eliminate the tumor

Additional and Relevant Useful Information for Localized Type Tenosynovial Giant Cell Tumor:

The synovial fluid is the lubricating fluid found in the joints (like knee, elbow), and synovium refers to the thin membrane that lines or covers the joint space.