Table 3.

Results of bivariate and multivariate analyses for tumor progression after stereotactic radiosurgery

	Bivariate		Multivariate
	HR [95% CI]	p-value	HR [95% CI]	p-value
Age, years (continuous)	1.02 [0.98–1.06]	0.385	–	–
Age > 70 years (vs. ≤ 70 years)	1.03 [0.46–2.32]	0.942	–	–
Male (vs. female)	1.23 [0.53–2.83]	0.628	–	–
Convexity, midline (vs. skull base)	0.88 [0.39–1.96]	0.748	–	–
Maximum diameter, mm (continuous)	1.00 [0.97–1.03]	0.858	–	–
Maximum diameter > 35 mm (vs. ≤ 35 mm)	0.78 [0.33–1.73]	0.511	–	–
Volume, mL (continuous)	1.02 [0.97–1.08]	0.378	1.03 [0.97–1.09]	0.315
Volume > 8 mL (vs. ≤ 8 mL)	0.85 [0.38–1.92]	0.694	–	–
Ki-67 LI, % (continuous)	1.04 [1.00–1.09]	0.047*	–	–
High LI (vs. low LI)	11.97 [1.46–98.04]	0.021*	12.71 [1.51–107.23]	0.019*
High LI (vs. intermediate LI)	3.43 [1.35–8.70]	0.010*	4.12 [1.54–11.04]	0.005*
History of radiation therapy	0.69 [0.27–1.75]	0.438	–	–
Salvage SRS (vs. adjuvant SRS)	0.50 [0.20–1.29]	0.152	0.59 [0.21–1.64]	0.309
Central dose, Gy (continuous)	1.04 [0.96–1.13]	0.395	–	–
Central dose > 36 Gy (vs. ≤ 36 Gy)	1.42 [0.63–3.19]	0.401	–	–
Marginal dose, Gy (continuous)	1.15 [0.94–1.40]	0.160	–	–
Marginal dose > 18 Gy (vs. ≤ 18 Gy)	0.54 [0.12–2.33]	0.408	–	–

CI confidence interval, HR hazard ratio, LI labeling index, SRS stereotactic radiosurgery

*p-values of < 0.05 are considered significant