Table 5.

Table summarising literature evaluating the survival benefit conferred by repeat resection for recurrent glioblastoma

Study	Study design	Total number of patients	Number of resections	Number of patients	Median survival (months)	Notes
Azoulay et al. [2]	Retrospective	136	1	68	5.3
			2	68	9.6
Chaichana et al. [22]	Retrospective	578	1	354	6.8	Risk of infections or iatrogenic deficits did not increase with repeat resections (p > 0.05)
			2	121	15.5
			3	41	22.4
			4	15	26.6
Delgado-Fernandez et al. [9]	Retrospective	121	1	90	/	The reoperation group had a median increase survival of 6.4 months compared with the non-reoperation group (p < 0.001)
			2	31	/
Djamel-Eddine et al. [11]	Retrospective	132	1	68	11
			2	53	16
			3	11	18
Filippini et al. [13]	Retrospective	676	1	503	/	Multivariable analysis showed no effect of reoperation on survival, whether performed within 9 months of the first surgery (HR 0.86, p 5 0.256) or after 9 months (HR 0.98; p 5 0.860)
			2	173	/
Goldman et al. [14]	Retrospective	163	1	74	/	When timing of repeat resection was ignored, repeat resection was associated with a lower risk of death (HR 0.62, p = 0.01). However, when timing was taken into account, repeat resection was associated with a higher risk of death (HR 2.19, p < 0.001)
			2	89	/
Mukherjee et al. [28]	Prospective	312	1	167	6.9	Complication rates were 5.5% and 6.2% following repeat resection and primary resection, respectively (p > 0.05)
			2	145	10.8
Nava et al. [23]	Prospective	764	1	368	/	HR for death after recurrence—1.05 (0.71–1.54) with reoperation vs conservative management
			2	138	/
Ortega et al. [24]	Retrospective	202	1	83	21.1	After adjusting for age, multiple resections were not an independent predictor of survival
			2	94	25.5
			3	25	29.0
Ringel et al. [15]	Retrospective	503	1	82	22.7
			2	421	29.3
			3	72	34.3
			4	9	26.4
Sastry et al. [30]	Retrospective	368	1	291	7.0
			2	77	12.8
Suchorska et al. [32]	Prospective	105	1	34	/	Post-recurrence survival (PRS) was 11.4 months (95% CI: 8.4–12.3) in patients who underwent surgery versus 9.8 months (95% CI: 6.6–15.1) in patients who did not undergo surgery (P 0.633)
			2	71	/
Tugcu et al. [33]	Retrospective	50	1	39	6.9
			2	11	9.6
Tully et al. [34]	Retrospective	204	1	105	9.0
			2	49	20.1
Woernle et al. [37]	Retrospective	98	1	58	14.8
			2	40	18.8
Wann et al. [36]	Retrospective	120	1	60	14
			2	60	22