Table 3.

Diagnosis example: atypical teratoid/rhabdoid tumor

	A	B
Integrated diagnosis	Atypical teratoid/rhabdoid tumor, WHO grade IV	Embryonal tumor with rhabdoid features, WHO grade IV
Histological classification	Embryonal tumor with rhabdoid features	Embryonal tumor with rhabdoid features
WHO grade	IV	IV
Molecular information	INI1 loss of protein expression/mutation or BRG1 loss of protein expression/mutation	INI1 and BRG1 protein expression retained/not mutated or molecular/immunohistochemical testing not performed

In this example, using the layered diagnosis format, the integrated diagnosis of atypical teratoid/rhabdoid tumor is only possible in the setting of either INI1 or BRG1 loss of protein expression or mutation (column A); without these findings, only a descriptive diagnosis is possible (column B). (Note that this is an example only and that the eventual definition will result from the WHO classification updating process.)