Soft tissue tumours- Synovial Tissue

Question 1

What is Pigmented Villonodular Synovitis?

Answer 1

• An Idopathic Monoarticular Reactive Synovial Disease
• characterised by Exuberant Proliferation of synovial villi and nodules
• Common adults 30-50 yrs
• M=F
• location
  
  • ​Knee 80%
  • hip , shoulder /ankle
• ​​​when extra-articular extension= Giant Cell Tumour of Tendon Sheath

Question 2

What is the pathology of Pigmented Villonodular Synovitis?

Answer 2

• 1/2 of pts report hx of trauma
• thought to be a reactive process

Question 3

What is the genetics of Pigmented Villonodular Synovitis?

Answer 3

• 5q33 Chromosomal Rearrangment
• increased expression of CSF1 gene

Question 4

What is the prognosis of Pigmented Villonodular Synovitis?

Answer 4

• Local reoccurrance is common

Question 5

What is the hx and presentation of a pt with Pigmented Villonodular Synovitis?

Answer 5

Hx

• 50% pts will have prior hx of trauma to the area

Symptoms

• Pain and swelling
• Mechanical Pain and limited motion
• Recurrent atraumatic haemathrosis ** hallmark**

O/E

• extra-articular GCT tendon sheath= Painless, soft, mass along tendon sheath
• intra-articular PVNS- joint effusion/erytherma

Question 6

What is seen on imaging of Pigmented Villonodular Synovitis?

Answer 6

Xrays

• Cystic erosion w sclerotic margins on both sides of the joint- see pic

CT

• Cystic erosions on both sides of joint

MRI

• Both low signal intensity on T1/T2= due to haemosiderin deposits

Question 7

What is seen on aspiration of the knee with Pigmented Villonodular Synovitis?

Answer 7

• Grossly bloody effusion
• Synovial biopsy should be done if any doubt of dx

Question 8

what is seen on Arthroscopy in a pt with pigmented villonodular synovitis?

Answer 8

• Brownish/Reddich inflamed synovium = pvns

Question 9

What is see on histology of PVNS?

Answer 9

• Haemosiderin Stained multinucleated Giant cells
• Highly vascular villi with hyperplastic synovial cells

Question 10

What is the tx of PVNS?

Answer 10

Non operative

• Observation
  
  • minimal role for non operative if disease symptomatic

Operative

• Total Synovectomy
  
  • in grossly symptomatic and painful disease
  • partial arthroscopic synovectomy vs open synovectomy- open can deal with posterior knee disease not arthroscopic
  • Freq recurrence is common= incomplete synovectomy
  • for extra-art disease
    
    • Marginal excision is adequate for GCT tendon sheath
    • recurrence ts with rpt excision
• external beam Irradiation
  
  • reduced rate of recurrence 10-20%
    *

Question 11

What are the adv/dis of athroscopic synovectomy?

Answer 11

• preform as through resection as possible
• excellent for focal or limited PVNS
• minimally invasive proceedure
• quick return to function
• unable to access posterior portion of joint
• unable to address extra-articular disease

Question 12

Decribe the technique for comnbined arthroscopis synovectomy and open posterior synovectomy of knee for PVNS?

Answer 12

• approach
  
  • post approach to knee via transverse /S incision across popliteal fossa
  • approach between heads of gastronemius
  • retract NV bundle to access posterior joint caspule
• technique
  
  • disease often seen posterior & extra-articular
  • complete post synovectomy & resection of extra-articular disease
• Adv
  
  • address all disease sections
  • thorough synovectomy
• Dis
  
  • Post approach to knee avoid NV bundle

Question 13

What is the tx for advanced PVNS disease?

Answer 13

• Total joint athroplasty and synovectomy
  
  • in advanced disease w severe degenerative joint
  • applicable to knee, hip , shoulder
• Total Synovectomy and arthrodesis
  
  • in severe disease of ankle

Question 14

What is the complication of PVNS?

Answer 14

• Reoccurrance
  
  • for both intra-articular and extra-articular disease
  • 30-50% recurrence rate despite synovectomy
  • reduced to 10-20% w external beam radiation

Question 15

What is synovial chondromatosis?

Answer 15

• A proliferative disease of the synovium assoc with cartilage metaplasia
• -> multiple intra-articular loose bodies
• ranges from synovial tissue to firm nodules of cartilage
• adults 30-50 yrs
• 2M:1F
• Knee most common location
• genetics
  
  • occasional chromosome 6 abnormalies found

Question 16

What is the presentation of synovial chondromatosis?

Answer 16

• Slow progression of symptoms
  Pain and swelling
• Pain worse with activity
• Mechanical symptoms including stiffness can occur in bursa overlying an osteochondroma

O/E

• reduced rom
• warmth, erytherma, tenderness

Question 17

What is seen on imaging of synovial chondromatosis?

Answer 17

xrays

• varible depends on stage of disease
• may show stippled calcification

MRI

• Initally cartilage nodules are obly visible on MRI
• lobular appearance
• in later stage, signal drop out consistent with calcification

Question 18

tx of synovial chondromatosis

Answer 18

Non operative

• Observation
  
  • mild symptoms not affecting rom

Operative

• Open or Arthroscopic Synovectomy and loose body resection +/- chondroplasty +/- labral debridement
  
  • severe symptoms affecting rom

Outcomes

• tx is symptomatic but may help prevent degenerative joint disease

Question 19

What is synovial sarcoma?

Answer 19

• Malignant soft tissue sarcoma which arises nr joints but rarely within joints
• the cell of origin is unknown
  
  • its is not the synovial cell so the name synovial sarcoma is a misnomer
• Most common sarcoma in young adults 15-40 yrs
• most common malignant sarcoma of the foot
• M>F
• Genetics= Chromosomal translocation t(X;18) in 90% cases-> SYT-SSX1,2 or 4 fusion protein
• ​Prognosis- overall poor
  
  • 5 yr survival approx 50% (w lymph node resectn)
  • 10 yr survival approx 25%

Question 20

What is the risk of metastatic spread in synovial sarcoma?

Answer 20

• Show high histological grade
• Mets may develop in 30-60% pts
• Lung is most common site (like other sarcomas)
• Can metastasize to Lymph nodes ( rare for Sarcomas)
  
  • poor prognostic sign
    but not as a lung mets
• can stage with lymph node biopsy
• Mets more common w large, deep high grade sarcomas

Question 21

Name the sarcomas that can metastasize to lymph nodes?

Answer 21

• Clear cell sarcomas
• Epitheloid sarcomas
• Angiosarcomas
• Rhabdomyosarcomas

= CLEAR

Question 22

What is the presentation of a pt with synovial sarcoma?

Answer 22

• Typically a Growing Mass in Proximity to joint
• Painless or painful
• Occur in Para-Articular locations
  
  • knee, shoulder, elbow, foot
  • 60% in lower extremity

​​O/E

• Examine for regional Lymphadenopathy

Question 23

What is seen on xrays of synovial sarcoma?

Answer 23

• Soft tissue mineralisation ( calcification) in these tumours
• may resemble Heterophic ossification

Question 24

What is seen on Ct of synovial sarcoma?

Answer 24

• Can show calcification in the soft tissue mass

MRI

• Heterogenous mass
• typical dark on T1 and bright on T2

Question 25

What is seen in histology with synovial sarcoma?

Answer 25

• Biphasic appearance
  
  • spindle cells
  • epithelial cells
    
    • glands, nest or cyst like cells- see pics
• Immunostaining for
  
  • Vimentin
  • epithelial membrane antigen
  • sporadic S-100
  • epithelial cells stain positive for Keratin

Question 26

What is the tx for synovial sarcoma?

Answer 26

• Operative
  
  • Wide Surgical Resection with Adjuvant radiotherapy
    
    • most pts
    • radiotx either neoadjuvant/adjuvant
    • chemotx may improve local control and overall survival