Effect of temozolomide on survival in elderly patients with glioblastoma and impaired performance status: a propensity score-matching analysis

Figures & data

Table 1 Baseline patient and treatment characteristics in the observational data set and in patients after propensity score matching

Characteristics	Observational data set (n=153)			Propensity score-matched data set (n=122)
	TMZ	BSC	P-value	TMZ	BSC	P-value
	n=78 (%)	n=75 (%)		n=61 (%)	n=61 (%)
Age at diagnosis, years	–	–	0.015	–	–	0.587
65–70	47 (60.3)	30 (40.0)	–	33 (54.1)	29 (47.5)	–
>70	31 (39.7)	45 (60.0)	–	28 (45.9)	32 (52.5)	–
KPS score	–	–	0.706	–	–	0.716
60–70	45 (57.7)	41 (54.7)	–	34 (55.7)	32 (52.5)	–
<60	33 (42.3)	34 (45.3)	–	27 (44.3)	29 (47.5)	–
Sex	–	–	0.517	–	–	0.856
Male	46 (58.9)	40 (53.3)	–	32 (52.5)	31 (50.8)	–
Female	32 (41.1)	35 (46.7)	–	29 (47.5)	30 (49.2)	–
Time of diagnosis	–	–	0.013	–	–	0.760
2006–2008	19 (24.4)	31 (41.3)	–	17 (27.9)	19 (31.1)	–
2009–2011	21 (26.9)	24 (32.0)	–	18 (29.5)	20 (32.8)	–
2012–2014	38 (48.7)	20 (26.7)	–	26 (42.6)	22 (36.1)	–
WIC	–	–	0.076	–	–	0.365
≥3	31 (39.7)	41 (54.7)	–	27 (44.3)	33 (54.1)	–
<3	47 (60.3)	34 (45.3)	–	34 (55.7)	28 (45.9)	–
MGMT methylation status	–	–	0.746	–	–	0.856
Methylated	33 (42.3)	34 (45.3)	–	29 (47.5)	30 (49.2)	–
Unmethylated	45 (57.7)	41 (54.7)	–	32 (52.5)	31 (50.8)	–
Serum albumin, g/L	–	–	0.901	–	–	0.810
<35	12 (15.4)	11 (14.7)	–	11 (18.0)	10 (16.4)	–
≥35	66 (84.6)	64 (85.3)	–	50 (82.0)	51 (83.6)	–
Extent of resection	–	–	0.416	–	–	0.717
Radical resection	30 (38.5)	34 (43.6)	–	27 (44.3)	30 (49.2)	–
Partial resection/biopsy	48 (61.5)	41 (54.7)	–	34 (55.7)	31 (50.8)	–

Abbreviations: BSC, best supportive care; KPS, Karnofsky performance status; TMZ, temozolomide; WIC, Charlson weighted index of comorbidities.

Figure 1 Kaplan–Meier estimated curves of (A) OS and (B) PFS in patients receiving TMZ vs BSC.

Abbreviations: BSC, best supportive care; OS, overall survival; PFS, progression-free survival; TMZ, temozolomide.

Table 2 Univariate and multivariate analyses in the propensity score-matched cohort (n=122)

Factors	OS				PFS
	Univariate analysis		Multivariate analysis		Univariate analysis		Multivariate analysis
	HR (95% CI)	P-value	HR (95% CI)	P-value	HR (95% CI)	P-value	HR (95% CI)	P-value
Age, years
65–70	Ref	–	Ref	–	Ref	–	–	–
>70	1.39 (1.02–2.28)	0.031	1.26 (0.89–1.69)	0.148	1.19 (0.68–2.85)	0.170	–	–
KPS score
60–70	Ref	–	Ref	–	Ref	–	Ref	–
<60	2.73 (1.58–7.29)	0.003	2.11 (1.48–7.67)	0.016	3.11 (1.89–11.34)	0.001	2.15 (1.18–8.33)	0.004
Sex
Male	Ref	–	–	–	Ref	–	–	–
Female	0.81 (0.53–1.19)	0.259	–	–	0.75 (0.26–1.33)	0.332	–	–
Time of diagnosis
2006–2008	Ref	–	–	–	Ref	–	–	–
2009–2011	1.28 (0.78–1.68)	0.268	–	–	1.13 (0.75–1.54)	0.549	–	–
2012–2014	0.86 (0.56–1.36)	0.093	–	–	0.89 (0.63–1.69)	0.186	–	–
WIC
≥3	Ref	–	–	–	Ref	–	–	–
<3	0.69 (0.59–1.15)	0.158	–	–	0.81 (0.52–1.33)	0.258	–	–
MGMT methylation status
Methylated	Ref	–	–	–	Ref	–	Ref	–
Unmethylated	0.65 (0.36–1.36)	0.169	–	–	0.29 (0.13–0.88)	0.006	0.33 (0.26–0.89)	0.013
Serum albumin, g/L
<35	Ref	–	–	–	Ref	–	–	–
≥35	0.89 (0.62–1.16)	0.158	–	–	0.93 (0.78–1.32)	0.328	–	–
Extent of resection
Radical resection	Ref	–	Ref	–	Ref	–	Ref	–
Partial resection/biopsy	2.69 (1.59–6.39)	0.003	1.98 (1.45–5.14)	0.026	4.15 (2.34–10.46)	<0.001	3.76 (2.58–7.36)	0.002
Treatment
TMZ	0.38 (0.17–0.70)	0.002	0.49 (0.23–0.87)	0.019	0.41 (0.21–0.76)	0.003	0.56 (0.29–0.81)	0.025
BSC	Ref	–	Ref	–	Ref	–	Ref	–

Abbreviations: BSC, best supportive care; HR, hazard ratio; Ref, reference; KPS, Karnofsky performance status; OS, overall survival; PFS, progression-free survival; TMZ, temozolomide; WIC, Charlson weighted index of comorbidities.

Table 3 Acute hematological toxicity (TMZ group, n=78)

Toxicities	CTC grade
	0	1	2	3	4
Anemia	32	28	15	3	0
Leukocytopenia	30	23	16	6	3
Neutropenia	14	34	25	3	2
Thrombocytopenia	15	26	29	8	2

Abbreviations: CTC, Common Terminology Criteria; TMZ, temozolomide.