Table 3.

GBM NR contact and recurrence.

Tumor relationship to NR at recurrence (%, 95% CI)
Contacting/total	86/102 (84%, 0.760–0.901)
Non-contacting/total	16/102 (16%, 0.099–0.240)
Recurrence pattern of contacting tumors at initial diagnosis (%, 95% CI)
Recurrent contacting tumor/total	49/49 (100%, 0.927–1)
Recurrent non-contacting tumor/total	0/49 (0%, 0–0.073)
Recurrence pattern of non-contacting tumors at initial diagnosis (%, 95% CI)
Recurrent contacting tumor/total	37/53 (70%, 0.565–0.805)
Recurrent non-contacting tumor	16/53 (30%, 0.195–0.435)
Mean minimum distance1 from NR to non-contacting GBM
Initial (cm)	1.73 (SEM: 0.261)
Recurrent (cm)	1.08 (SEM: 0.256)
Paired t-test p-value	0.0006
Local tumor recurrence with respect to PTV1 (%, 95% CI)
Local recurrences/total	79 (77%, 0.684–0.845)
Initial contacting tumor local recurrence/contacting tumors	33/49 (67%, 0.534–0.788)
Initial non-contacting tumor local recurrence/non-contacting tumors	46/53 (87%, 0.752–0.935)
Distant tumor recurrence with respect to PTV1 (%, 95% CI)
Distant recurrences/total	23 (23%, 0.155–0.316)
Initial contacting tumor distant recurrence/contacting tumors	16/49 (33%, 0.212–0.466)
Initial non-contacting tumor distant recurrence/non-contacting tumors	7/53 (13%, 0.065–0.248)
Chi-squared test p-value	0.0315 (OR2: 3.19, 1.18–8.62)
Clinical factors as predictors of NR recurrence
Age	p = 0.414 (OR: 0.482)
Extent of resection	p = 0.216 (OR: 2.258)
Performance status	p = 0.698 (OR: 0.618)
Initial tumor NR contact	p = 0.024 (OR: 2.45e–10)

Abbreviations: CI = confidence interval, OR = Odds ratio.

¹Mean minimum distance between neurogenic regions and tumor contrast enhancement.