Table 7. Adjuvant treatment for patients with WHO grade 2 diffuse astrocytoma, IDH-wildtype by KSNO, NCCN, and EANO guideline.

Guidelines	Adjuvant treatment
KSNO	1) Standard RT & adjuvant temozolomide chemotherapy (Level III)
	2) Standard RT alone
	3) Observation
NCCN*	- For patients with KPS ≥60
		1) Standard RT & followed adjuvant temozolomide chemotherapy
		2) Standard RT with concurrent & adjuvant temozolomide chemotherapy
	- For patient with KPS <60
		1) RT (hypofractionated) alone
		2) Temozolomide chemotherapy, if MGMT promoter methylated (category 2B)
		3) Palliative/best supportive care
EANO	1) Wait-and-see
	2) RT (50–54 Gy in 1.8–2.0 Gy fractions)
	3) RT followed by PCV or Temozolomide CCRT (determined by MGMT status)

^*Same guideline for patients with WHO grade 3 anaplastic astrocytoma. CCRT, concurrent chemoradiotherapy; EANO, European Association of Neuro-Oncology; IDH, isocitrate dehydrogenase; KPS, Karnofsky Performance Scale; KSNO, Korean Society for Neuro-Oncology; MGMT, O⁶-methylguanine-DNA-methyltrasferase; NCCN, National Comprehensive Cancer Network; PCV, procarbazine, CCNU, and vincristine; RT, radiotherapy; WHO, World Health Organization