The Prognostic Value Of Lymph Node Ratio In Patients With N2 Stage Lung Squamous Cell Carcinoma: A Nomogram And Heat Map Approach

Figures & data

Table 1 Demographic And Clinicopathological Characteristics Of The Patients In The Training Cohort And Validation Cohort

Characteristic	Training Cohort (n=1778)	Validation Cohort (n=146)	P value
Age, year (mean±SD)	66.41±9.51	60.03±9.02	<0.0001
≤60	483	81	<0.001
60~70	646	49
>70	649	16
Gender
Male	1177	135	<0.001
Female	601	11
Laterality			0.052
Left	830	56
Right	948	90
Type of surgery			0.013
Lobectomy	1406	128
Pneumonectomy	372	18
Chemotherapy			<0.001
No	591	92
Yes	1187	54
Postoperative Radiotherapy			<0.001
No	1211	567
Yes	112	18
T category			<0.001
T1	329	8
T2	651	67
T3	448	48
T4	350	23
Grade			0.306
Well differentiated	22	2
Medium/poorly differentiated	1637	140
Undifferentiated	20	1
Unknow	99	3
LNs resected			<0.001
<12	867	29
≥12	911	117

Abbreviations: SD, standard deviation; LNs, lymph nodes.

Figure 1 Selection of patients included in the study.

Figure 2 Kaplan-Meier curves of overall survival (A) and cancer specific survival (C) stratified by lymph node ratio (LNR) in the training cohort; overall survival (B) and cancer specific survival (D) stratified by LNR in the validation cohort.

Figure 3 Overall survival according to the recipient of postoperative radiotherapy in patients with lower (≤0.42, A) and higher (>0.42, B) LNR.

Table 2 Univariate And Multivariate Analysis Of Prognostic Factors Potentially Correlated With OS And CSS Of Patients With Resected N2 Stage Lung Squamous Cell Carcinoma In The Training Cohort

Variable	OS		p	CSS		p
	Univariable	Multivariable		Univariable	Multivariable
	p	HR (95% CI)		p	HR (95% CI)
Age
≤60	–	–	–	–
60~70	0.035	1.17(1.01~1.36)	0.039	0.170	1.15(0.96~1.38)	0.135
>70	<0.001	1.55(1.33~1.81)	<0.001	0.044	1.23(1.01~1.49)	0.043
Gender (female vs male)	0.003	0.86(0.76~0.98)	0.020	0.042
Laterality (right vs left)	0.023	1.21(1.08~1.36)	0.001	0.034	1.27(1.09~1.47)	0.002
Surgery (pneumonectomy vs lobectomy)	0.025	1.26(1.09~1.46)	0.002	0.001	1.35(1.12~1.61)	0.001
Chemotherapy (yes vs no)	<0.001	0.57(0.51~0.64)	<0.001	<0.001	0.64(0.55~0.75)	<0.001
Postoperative radiotherapy (yes vs no)	0.046			0.21
T category
T1	–	–	–	–	–	–
T2	0.012	1.27(1.08~1.51)	0.004	<0.001	1.56(1.23~1.96)	<0.001
T3	<0.001	1.50(1.25~1.80)	<0.001	<0.001	1.91(1.49~2.48)	<0.001
T4	<0.001	1.52(1.26~1.83)	<0.001	<0.001	1.92(1.49~2.48)	<0.001
Grade
Well differentiated	–			–
Medium/poorly differentiated	0.587			0.914
Anaplastic	0.395			0.491
Unknow	0.958			0.561
LNs resected (≥12 vs <12)	0.113			0.681
LNR (>0.42 vs ≤0.42)	<0.001	1.41(1.24~1.61)	<0.001	<0.001	1.49(1.26~1.76)	<0.001

Abbreviations: OS, overall survival; CSS, cancer-specific survival; LNs, lymph nodes; LNR lymph node ratio.

Figure 4 Nomogram for patients with resected N2 stage lung squamous carcinoma derived from the training cohort. After summing up the total score and locating it on the Total Points scale, a line drawn straight down to the 1-, 3-, 5-year Survival scale shows the survival probability at each time points.

Figure 5 Calibration curves for 1-, 3-, 5-year survival probabilities in the training cohort (A, B, C) and in the external validation cohort (D, E, F). Nomogram-predicted survival is plotted on the x axis and observed survival on the y axis. The vertical bars at the top represent the frequency of the predicted probability of survival. A plot along the 45-degree gray line indicates a perfect calibration model where the predicted probabilities are identical to the actual proportions.

Figure 6 Heatmaps of the number of positive lymph node (x axis) and lymph node ratio (y axis) corresponding to 1-, 3-, 5-year overall survival probabilities (A, B, C) and cancer specific survival (D, E, F).