An atypical teratoid / rhabdoid tumour (ATRT) is an uncommon WHO Grade IV tumour which in the vast majority of cases occurs in young children less that two years of age. It most frequently presents as a posterior fossa mass.
AT/RT's were until relatively recently classed as medulloblastomas, although both clinically and histologically they are different entities.
They present in young children (median age is less than 2 - 3 years 2), whereas medulloblastomas typically occur in mid childhood (median age 6 years).
Rhabdoid cells are the hallmark of AT/RT which however make up only a tiny fraction of the tumour, which is otherwise indistinguishable from a medulloblastoma / sPNET.
Relatively specific markers include
- epithelial membrane antigen
- smooth muscle actin
- infratentorial : ~ 50 %
- often iso-dense to gray matter
- may demonstrate heterogeneous enhancement
- calcification is common
- may show associated obstructive hydrocephalus
Can show necrosis, multiple foci of cyst formation and sometimes haemorrhage
- T1 : iso to slightly hyper intense to grey matter (haemorrhagic areas can be more hyper intense)
- T2 : generally hyper intense (haemorrhagic areas can be hypo intense)
- T1 C+ (Gd) : heterogeneous enhancement
MR spectroscopy :
- Cho : elevated
- NAA : decreased
Treatment and prognosis
Surgery with debulking can be offered in some cases. Tumours can demonstrate leptomeningeal dissemination. Clinically AT / RTs have much poorer prognosis than medulloblastomas, with little if any response to chemotherapy, and death usually occuring within a year of diagnosis.
- 1. Barkovich AJ. Pediatric neuroimaging. Lippincott Williams & Wilkins. (2005) ISBN:0781757665. Read it at Google Books - Find it at Amazon
- 2. Meyers SP, Khademian ZP, Biegel JA et-al. Primary intracranial atypical teratoid/rhabdoid tumors of infancy and childhood: MRI features and patient outcomes. AJNR Am J Neuroradiol. 2006;27 (5): 962-71. AJNR Am J Neuroradiol (full text) - Pubmed citation
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- 4. Arslanoglu A, Aygun N, Tekhtani D et-al. Imaging findings of CNS atypical teratoid/rhabdoid tumors. AJNR Am J Neuroradiol. 2004;25 (3): 476-80. AJNR Am J Neuroradiol (full text) - Pubmed citation
- 5. Han L, Qiu Y, Xie C et-al. Atypical teratoid/rhabdoid tumors in adult patients: CT and MR imaging features. AJNR Am J Neuroradiol. 2011;32 (1): 103-8. doi:10.3174/ajnr.A2361 - Pubmed citation
- 6. Koral K, Gargan L, Bowers DC et-al. Imaging characteristics of atypical teratoid-rhabdoid tumor in children compared with medulloblastoma. AJR Am J Roentgenol. 2008;190 (3): 809-14. doi:10.2214/AJR.07.3069 - Pubmed citation
Synonyms & Alternative Spellings
|Synonyms or Alternative Spelling||Include in Listings?|
|Atypical teratoid / rhabdoid tumour||✗|
|Atypical teratoid / rhabdoid tumour (AT/RT)||✗|