Atypical teratoid-rhabdoid tumor in a teenager: a clinical example of a complex diagnostic search

Atypical teratoid rhabdoid tumor (AT/RT) of the central nervous system is a highly aggressive malignant neoplasm with a poor prognosis predominantly affecting younger children. The main criterion for diagnosing AT/RT in immunohistochemical studies is the lack of expression of the INI-1 protein with anti-INI-1 antibodies; in complex cases, molecular genetic techniques can be additionally applied, for example, DNA methylation study (Illumina 450 (850) K array). This clinical example demonstrates the difficulties of diagnosis of AT/RT at an older age, emphasizes the need of using additional diagnostic methods and revising histological material in reference centers, including international ones.