dermatologic- soft tissue tumours

Question 1

What is squamous cell carcinoma?

Answer 1

• A malignant soft tissue tumour found in older pts
• location
  
  • dorsum hand/ forearm
  • most common subungual malignancy
• Risk factors
  
  • excessive exposure to UV radiation
  • actinokeratosis
  • chronic osteomyelitis
    
    • Marjolin’s ulcer is a SCC from chronic draining wounds or burn scars

Question 2

What is the prognosis of squamous cell carcinoma?

Answer 2

• Mets
  
  • Lymph node mets & high histologic grade- confer poor prognosis
  • Higher metastatic potential than basal cell carcinoma

Question 3

What are the symptoms of squamous cell carcinoma?

Answer 3

• Pain

Question 4

What is seen on xrays of squamous cell carcinoma?

Answer 4

• Lytic lesion

Question 5

What is the tx of squamous cell carcinoma?

Answer 5

Operative

• Wide surgical resection +/- Skin graft+/- radiation
  
  • standard tx
  • • radiotherapy if
      
      • >2cm wide
      • 4mm deep
      • perineural invasion
      • lymph node mets
• Mohs microsurgery
  
  • becoming more popular
  • smaller lesions
  • highest cure rate
  • lymph node biopsy maybe necessary

Question 6

What is a glomus tumour?

Answer 6

• A rare benign tumour of the glomus body, often occuring in subungual region
• amy involve either soft tissue + bone
• assoc w delay in dx
• aka paraganglioma
• pts 20-40yrs
• location
  
  • hand 75%
  • 50% subungual
  • 50% erosions of distal phalanx
  • less common palm,wrist , forearm,foot

Question 7

What is a glomus body?

Answer 7

• A **perivascular temperature regulating structure **
• frequently located at tip of a digit or beneath the nail

Question 8

What is the presentation of a glomus tumour?

Answer 8

symptoms- classical triad

• paroxysmal pain
• equisite tenderness to touch
• cold intolerance

o/E

• Small bluish nodule
• often difficult to see, esp in subungual region
• nail ridging or discolouration is common

Question 9

What is seen on imaging of glomus tumour?

Answer 9

• xrays
  
  • glomus tumour can produce pressure erosion os the underlying bone & assoc with deformity of the bone cortex
• ​MRI
  
  • useful for dx
  • ​low on T1, high signal T2

Question 10

What is seen on histology of glomus tumour?

Answer 10

• Gland like nest structures
• small round cells with dark nuclei

Question 11

What is the tx of glomus tumour?

Answer 11

Operative

• Marginal excision is curative
  
  • symptoms affecting quality of life
  • recurrence uncommon
  • several cases of malignant glomus tumour have been reported