Clinical significance of serum cathepsin B and cystatin C levels and their ratio in the prognosis of patients with esophageal cancer

Figures & data

Table 1 Serum CTSB, CysC and CysC/CTSB levels in esophageal carcinoma patients and healthy population

Indexes	Patients (N=56)		Controls (n=30)		P-value
	Mean (±SD)	Median (min–max)	Mean (±SD)	Median (min–max)
CSTB (ng/mL)	38.35±4.3	38.14 (20.97–62.72)	22.35±1.8	21.39 (13.21–48.37)	0.001
CysC (ng/mL)	703.96±23.6	698.72 (440.51–1,424.48)	501.97±11.5	492.63 (325.25–1,136.74)	0.001
CysC/CSTB	18.71±2.96	18.85 (14.87–24.27)	22.21±3.75	21.73 (15.26–28.21)	0.093

Abbreviations: CTSB, cathepsin B; CysC, cystatin C; SD, standard deviation; min, minimum; max, maximum.

Table 2 The correlation between clinicopathologic characteristics and serum CTSB or serum CysC

Characteristic	n	CTSB		CysC		CysC/CTSB
		Mean ± SD	P-value	Mean ± SD	P-value	Mean ± SD	P-value
Age (years)			0.412a		0.428a		0.510a
≥58.5	28	39.17±2.51		725.34±9.19		18.59±2.65
<58.5	28	37.44±3.26		681.55±13.39		18.08±1.89
Gender			0.341a		0.212a		0.635a
Male	31	39.46±2.34		733.89±11.81		18.55±2.71
Female	25	37.24±4.51		673.61±8.67		17.66±1.94
Pathologic type			0.631a		0.621a		0.378a
SCC	50	38.13±2.61		701.44±16.62		18.42±2.46
ADC	6	39.65±3.64		723.74±13.74		18.22±2.07
Grade			0.459b		0.771b		0.169b
G1	11	37.57±6.98		702.34±13.69		18.71±2.39
G2	25	39.36±2.99		716.35±9.00		18.18±2.28
G3	20	38.32±5.21		688.98±12.33		18.10±1.88
T status			0.008a		0.459a		0.001a
T1 + T2	24	29.35±3.38		693.18±14.62		22.57±2.73
T3 + T4	32	45.12±4.56		711.40±9.88		16.28±1.87
Lymph node metastasis			0.871a		0.239a		0.001a
No	20	38.81±4.71		729.14±8.32		19.36±2.28
Yes	36	38.17±2.86		687.58±11.89		15.28±1.64

Notes:

a Mann–Whitney U test,

b Kruskal–Wallis test.

Abbreviations: ADC, adenocarcinoma; CTSB, cathepsin B; CysC, cystatin C; IQ, interquartile; SCC, squamous cell carcinoma; SD, standard deviation.

Figure 1 Kaplan–Meier curve of overall survival for patients with low and high levels of CysC/CTSB.

Abbreviations: CTSB, cathepsin B; CysC, cystatin C.

Figure 2 Kaplan–Meier curve of overall survival for patients in T3 + T4 group with low and high levels of CysC/CTSB.

Abbreviations: CTSB, cathepsin B; CysC, cystatin C.

Figure 3 Kaplan–Meier curve of overall survival for patients in T1 + T2 group with low and high levels of CysC/CTSB.

Abbreviations: CTSB, cathepsin B; CysC, cystatin C.

Figure 4 Kaplan–Meier curve of overall survival for patients with positive lymph node metastasis versus negative lymph node metastasis.

Figure 5 Kaplan–Meier curve of overall survival for patients with low and high levels of CTSB.

Abbreviation: CTSB, cathepsin B.

Table 3 Univariate and multivariate analyses of CysC, CTSB and other potential factors for EC prognosis

Characteristics	n	Overall survival (months)	Univariate analysis		Multivariate analysis
			P-value	RR	P-value	RR
Age (years)
≥58.5	28	30.4	0.159	1.491	0.267	1.522
<58.5	28	33.3
Gender
Male	31	34.7	0.108	1.109	0.134	2.043
Female	25	29.1
Pathologic type
SCC	50	31.7	0.318	1.455	0.204	1.517
ADC	6	28.1
Grade
G1 + G2	36	34.4	0.175	1.074	0.127	1.353
G3	20	27.5
T stage
T1 + T2	24	36.1	0.458	1.373	0.671	1.564
T3 + T4	32	28.9
LNM
No	20	38.1	0.01	1.357	0.007	1.606
Yes	36	27
CysC/CTSB
<18.85	26	38.5	0.001	2.253	0.001	2.411
≥18.85	30	26.2
CTSB
≥38.14	27	35.9	0.081	0.969	0.065	1.518
≥38.14	29	28.5
CysC
<698.72	28	33.6	0.152	1.177	0.183	0.923
≥698.72	28	29.3

Abbreviations: CTSB, cathepsin B; CysC, cystatin C; EC, esophageal cancer; LNM, lymph node metastasis; RR, relative risk.