Table 1.

Definitions of meningioma histology groups: The SEER‐18 registry database

Histology group	ICD‐O‐3 code	Specific histology classification
Meningioma, NOS	9530	Meningioma, NOS; Meningiomatosis, NOS; Meningioma, malignant
Meningothelial meningioma	9531	Meningothelial meningioma; Meningothelial meningioma, borderline; Meningothelial meningioma, malignant
Fibrous meningioma	9532	Fibrous meningioma; Fibrous meningioma, malignant
Psammomatous meningioma	9533	Psammomatous meningioma
Angiomatous meningioma	9534	Angiomatous meningioma; Angiomatous meningioma, malignant
Hemangioblastic meningioma	9535	Hemangioblastic meningioma; Hemangioblastic meningioma malignant
Transitional meningioma	9537	Transitional meningioma; Transitional meningioma, malignant
Clear cell meningioma	9538	Clear cell meningioma, benign; Clear cell meningioma; Papillary meningioma
Atypical meningioma	9539	Atypical meningioma, benign; Atypical meningioma
Meningeal sarcomatosis	9539	Meningeal sarcomatosis