Week 3, Day 3, Slides 27-28

Romantic Colon Biopsy 

27) 15-year-old boy with a deeply situated 4.6-cm mass of the calf region, present for at least four years and slowly growing.
http://bit.ly/1ohfg7S


28) Male 25 years with an intramuscular mass left upper back.
Immunohistochemistry: POS: Vimentin / NEG: Desmin, S100, Cytokeratin, EMA, CD34
http://bit.ly/1m4tYAw

Both tumors would now be considered Low-grade fibromyxoid sarcomas.

Young adults, Deep seated in Limbs
Late mets to the lungs common
Swirling fascicles of bland, uniform Spindled fibroblasts alternating with myxoid areas
As in the name low grade nuclei and minimal mitotic activity

MUC4+ new sensitive and specific Ab (we dont have it)

**t(7;16)(q34;p11) TLS–CREB3L2**

This translocation is also found in slide 28 which previously would have been called Hyalinizing spindle cell tumor with giant collagen rosettes which prompted reclassification (the rosettes were previously seen in ~10% of all LGFMS)