Atypical teratoid/rhabdoid tumour

From Libre Pathology
Revision as of 03:23, 17 February 2014 by Michael (talk | contribs)
Jump to navigation Jump to search

Atypical teratoid/rhabdoid tumour, abbreviated AT/RT, is malignant tumour usually found supratentorially.

It may be written atypical teratoid rhabdoid tumour, i.e. without the forward slash (abbreviated ATRT, or atypical teratoid-rhabdoid tumour (abbreviated AT-RT).

It should not be confused with the extrarenal malignant rhabdoid tumour.

General

  • Usually supratentorial, occasionally in posterior fossa, case reports of spinal cord.
  • Individuals usually <3 years old, uncommon in adults.[1]
  • Prognosis very poor.[1]

Microscopic

Features:

  • Cellular.
  • Small round cells usu. with a prominent nucleolus.
  • Rhabdoid cells.
    • Cells with eosinophilic granular cytoplasm + eccentric nucleus.
  • Mitoses.
  • +/-Necrosis (common).

DDx:

Images

www:

IHC

  • BAF-47 -ve (AKA INI1, AKA SMARCB1 - the HGNC symbol[2]) - virtually diagnostic.
    • Endothelial cells +ve control.
  • S-100 +ve.
    • Few other brain tumours express it.
  • Vimentin +ve (perinuclear condensation).

Others:

  • GFAP +ve (focal - in tumour cells).
  • EMA +ve (patchy cytoplasmic).
  • Smooth muscle actin +ve.

See also

References

  1. 1.0 1.1 Kanoto, M.; Toyoguchi, Y.; Hosoya, T.; Kuchiki, M.; Sugai, Y. (Jan 2014). "Radiological Image Features of the Atypical Teratoid/Rhabdoid Tumor in Adults: A Systematic Review.". Clin Neuroradiol. doi:10.1007/s00062-013-0282-2. PMID 24477665.
  2. Online 'Mendelian Inheritance in Man' (OMIM) 601607