9 days old baby (gender not specified) with resected nasopharyngeal tumor (inherited).  
MACRO: Polypoid epithelium covered white 1,9x1,4x0,9 cm fragment and 3 smaller brown tissue pieces.  
HISTO: Chondroid, glandular, epithelial and glial/ganglial structures with choroid plexus like elements (mature teratoma). Exulceration, covered by granulation tissue.  
In stroma, perivascular cuffs of atypical "blastoid" eosinophilic cells with eccentric nuclei, focal maturation and immunophenotype of myeloid line with some TdT+ Pax5+ B haematogone admixture. Any mega- or erythroid- elements present (no signs of bi or trilineage diff).  
 
PROPOSAL:  
Mature (nasopharyngeal) teratoma with myeloid blastic and smaller B lymphoblastic prolfieration (extramedulary haematopoiesis like?), probably benign.  
 
Thanxforalldone.

tzankov 2014-10-06 09:38	I agree with you interpretation, yet a FACS work-up of the peripheral bloood is warranted
ugnius 2014-10-06 10:28	thanx hematologists are aware of it.