Table 1. Clinical presentation of GBM patients with lowest and highest CSF Igf2 concentrations.

Patients with the lowest CSF Igf2 concentrations (L1-L3) had early or stable GBM disease state, while patients with the highest CSF Igf2 concentrations (H1-H3) had advanced disease and aggressive tumor progression at time of CSF collection. Tumor size was determined by Macdonald’s criteria, where T1-Gad MRI sequence delineated the contrast-enhanced portion of tumor, and FLAIR images include areas of non-vascularized and invasive tumor (Macdonald et al., 1990). High CSF Igf2 patients had larger T1-Gad tumor sizes compared to low CSF Igf2 patients (Mann-Whitney; p < 0.05; n=3).

	Patient	[Igf2] ng/ml	Clinical Presentation
			Tumor size: T1-Gad (cm2)	Tumor size: FLAIR (cm2)	Lifespan
Low CSF Igf2	L1	142.1	7.14	6.46	Stable disease at follow-up; 3 weeks post CSF collection
	L2	145.4	8.50	54.12	Stable disease at follow-up; 3 weeks post CSF collection
	L3	153.9	5.94	20.5	Stable disease at follow-up; 5 weeks post CSF collection
High CSF Igf2	H1	605.8	47.31	102.83	Deceased at 1 week post CSF collection
	H2	502.8	13.69	53.90	Deceased at 52 weeks post CSF collection
	H3	468.7	23.94	36.48	Deceased at 30 weeks post CSF collection