Systemic Inflammation Response Index (SIRI) Independently Predicts Survival in Advanced Lung Adenocarcinoma Patients Treated with First-Generation EGFR-TKIs

Figures & data

Table 1 Clinicopathological Characteristics of 245 Patients

Characteristics	Number (%)
Age
Median	60
Range	28–88
Gender
Male	107(43.7)
Female	138(56.3)
Smoking status
Non-smoker	176(71.8)
Current or ex-smoker	69(28.2)
ECOG PS
0	38(15.5)
1	166(67.8)
2	41(16.7)
Brain metastasis
Yes	26(10.6)
No	219(89.4)
EGFR mutation
L858R	101(41.2)
19-DEL	134(54.7)
Other	10(4.1)
NLR
High	82(33.5)
Low	163(66.5)
PLR
High	52(21.2)
Low	193(78.8)
SIRI
High	90(36.7)
Low	155(63.3)

Abbreviations: ECOG PS, Eastern Cooperative Oncology Group performance status; SIRI, systemic immune response index; NLR, neutrophil to lymphocyte ratio; PLR, platelet to lymphocyte ratio.

Table 2 The Association of SIRI, NLR, and PLR with Clinicopathologic Characteristics in 245 Patients with Advanced Lung Adenocarcinoma

Characteristics	SIRI <0.71	SIRI ≥0.71	P	NLR <3.36	NLR ≥3.36	P	PLR <167.01	PLR ≥167.01	P
Age
<65	41(16.7%)	136(55.5%)	0.606	102(41.6%)	75(30.6%)	0.251	87(35.5%)	90(36.7%)	0.669
≥65	13(5.3%)	55(22.4%)		33(13.5%)	35(14.3%)		36(14.7%)	32(13.1%)
Gender
Female	42(17.1%)	96(39.2%)	<0.001	85(34.7%)	53(21.6%)	0.028	68(27.8%)	70(28.6%)	0.797
Male	12(4.9%)	95(38.8%)		50(20.4%)	57(23.3%)		55(22.4%)	52(21.2%)
Smoking status
No	47(19.2%)	129(52.7%)	0.006	98(40.0%)	78(31.8%)	0.777	83(33.9%)	93(38.0%)	0.156
Yes	7(2.9%)	62(25.3%)		37(15.1%)	32(13.1%)		40(16.3%)	29(11.8%)
ECOG PS
0–1	50(20.4%)	154(62.9%)	0.039	121(49.4%)	83(33.9%)	0.004	111(45.3%)	93(38.0%)	0.004
2	4(1.6%)	37(15.1%)		14(5.7%)	27(11.0%)		12(4.9%)	29(11.8%)
Brain metastasis
No	47(19.2%)	172(70.2%)	0.616	122(49.8%)	97(39.6%)	0.678	110(44.9%)	109(44.5%)	1.000
Yes	7(2.9%)	19(7.8%)		13(5.3%)	13(5.3%)		13(5.3%)	13(5.3%)
EGFR mutation
19-DEL	27(11.0%)	107(43.7%)	0.001	70(28.6%)	64(26.1%)	0.014	63(25.7%)	71(29.0%)	0.125
L858R	20(8.2%)	81(33.1%)		55(22.4%)	46(18.8%)		52(21.2%)	49(20.0%)
Other	7(2.9%)	3(1.2%)		10(4.1%)	0(0%)		8(3.3%)	2(0.8%)

Abbreviations: ECOG PS, Eastern Cooperative Oncology Group performance status; SIRI, systemic immune response index; NLR, neutrophil to lymphocyte ratio; PLR, platelet to lymphocyte ratio.

Table 3 Univariate Analysis of Potential Factors Associated with PFS and OS

Variables	PFS			OS
	Case	MST(m)	P	Case	MST(m)	P
Age
<65	177	14.8(12.7–15.3)	0.279	177	25.2(22.5–27.5)	0.264
≥65	68	14.3(11.4–16.6)		68	26.8(22.3–31.7)
Gender
Male	107	11.6(10.7–13.3)	0.057	107	28.2(25.9–30.1)	0.010
Female	138	14.4(12.8–15.2)		138	24.1(20.8–27.2)
Smoking status
No	176	14.2(12.3–15.7)	0.052	176	27.4(23.7–30.3)	0.084
Yes	69	11.7(10.6–13.4)		69	23.8(22.7–25.3)
ECOG PS
0–1	204	14.4(12.4–15.6)	0.007	204	28.3(25.7–30.3)	<0.001
2	41	10.7(9.3–12.7)		41	18.6(16.3–21.7)
Brain metastasis
Yes	26	11.1(9.4–12.6)	0.043	26	22.8(19.1–26.9)	0.038
No	219	14.4(12.4–15.6)		219	26.2(23.7–28.3)
EGFR mutation
L858R	101	11.9(10.1–13.9)	0.590	101	24.1(17.7–30.3)	0.829
19-DEL	134	14.4(12.0–16.0)		134	25.6(23.0–27.0)
Other	10	12.0(NR)		10	25.2(NR)
NLR
<3.36	135	14.8(13.6–16.4)	0.128	135	27.8(26.1–29.9)	0.004
≥3.36	110	11.7(10.8–13.2)		110	21.7(19.4–24.6)
PLR
<167.01	123	14.3(11.7–16.3)	0.268	123	26.8(23.5–30.5)	0.281
≥167.01	122	11.8(10.6–13.4)		122	23.9(21.4–26.6)
SIRI
<0.71	54	16.4(NR)	0.002	54	NR	0.001
≥0.71	191	11.6(10.7–13.3)		191	23.8(21.7–26.3)

Abbreviations: ECOG PS, Eastern Cooperative Oncology Group performance status; SIRI, systemic immune response index; NLR, neutrophil to lymphocyte ratio; PLR, platelet to lymphocyte ratio; OS, overall survival; PFS, progression-free survival; MST, mean survival time.

Table 4 Multivariable Cox Regression Analyses for PFS and OS

Variables	PFS		OS
	HR (95% CI)	P	HR (95% CI)	P
ECOG PS
0–1
2	2.562(1.667–3.940)	<0.001	2.431(1.571–3.761)	<0.001
Brain metastasis
Yes	1.630(0.980–2.711)	0.060	1.495(0.886–2.525)	0.132
No
Gender
Female			1.206(0.825–1.761)	0.333
Male
NLR
≥3.36			1.275 (0.860–1.867)	0.212
<3.36
SIRI
≥0.71	2.384(1.275–4.459)	0.007	1.721 (1.024–3.898)	0.042
<0.71

Abbreviations: ECOG PS, Eastern Cooperative Oncology Group performance status; SIRI, systemic immune response index; NLR, neutrophil to lymphocyte ratio; OS, overall survival; PFS, progression-free survival.

Figure 1 Kaplan–Meier survival curves for progression-free survival (PFS) according to NLR (A), PLR (B), and SIRI (C), and overall survival (OS) according to NLR (D), PLR (E) and SIRI (F) in EGFR-mutant lung adenocarcinoma patients treated with first-generation EGFR-TKIs.

Abbreviations: NLR, neutrophil to lymphocyte ratio; PLR, platelet to lymphocyte ratio; SIRI, systemic inflammation response index.