8. 32 year-old male presents with a right upper arm nodulel, showing dermal proliferation It is positive for Factor XIIIa and negative with CD34. The epidermis is unremarkable, with minimal acanthosis. Deep dermal infiltration by fibroblasts is noted. The best diagnosis is:

  1. Dermatofibroma
  2. Neurofibroma
  3. Leiomyosarcoma
  4. Dermatofibrosarcoma protuberans
  5. Sclerotic fibroma