Clinical value of carbon nanoparticles in identifying metastatic lymph nodes in colorectal cancer: A single-center observational study

Table 1 Clinicopathologic characteristics of patients, mean ± SD/n (%)

Variables	Patients (n = 146)
Gender
Male	91 (62.3)
Female	55 (37.7)
Age, year	64.9 ± 9.7
Tumor stage
I	57 (39.0)
II	41 (28.1)
III	36 (24.7)
IV	12 (8.2)
Tumor differentiation
Well	13 (8.9)
Moderate	91 (62.3)
Poor	42 (28.8)
Preoperative therapy	9 (6.2)
Tumor location
Rectum	65 (44.5)
Sigmoid	52 (35.6)
Descending	14 (9.6)
Right colon	15 (10.3)
Surgical approach
Laparoscopic	114 (78.1)
Robotic	32 (21.9)
Number of LNs	22.0 ± 9.2
Metastatic LNs	0.9 ± 2.0

LNs: Lymph nodes.

Table 2 The distribution of stained and metastatic lymph nodes, n (%)

Variables	Staining (n = 146)	Non-staining (n = 146)	P value
Number of LNs	2789	423	< 0.001a
D1	1581 (56.7)	337 (79.7)
D2	832 (29.8)	60 (14.2)
D3	376 (13.5)	26 (6.1)
Metastatic status of LNs			< 0.001a
Non-metastatic LNs	2712 (97.2)	364 (86.1)
Metastatic LNs	77 (2.8)	59 (13.9)
Number of LNs			< 0.001a
LVI negative	2376 (85.2)	332 (78.5)
LVI positive	413 (14.8)	91 (21.5)
Non-regional LNs (n = 9)	25	7	0.042a
Non-metastatic LNs	25 (100)	2 (28.6)
Metastatic LNs	0 (0)	5 (71.4)
Tumor deposits (n = 16)	2 (5.3)	36 (94.7)

^aP < 0.05.

LNs: Lymph nodes; D1: Pericolic/perirectal lymph node; D2: Intermediate lymph node; D3: Main lymph node; LVI: Lymphovascular invasion.

Table 3 The distribution of lymph nodes according to different T stages, n (%)

Variables	Staining (n = 137)	Non-staining (n = 137)	P value
T1 patients (n = 40)	733	27	< 0.001a
Non-metastatic LNs	728 (99.3)	26 (79.7)
Metastatic LNs	5 (0.7)	1 (14.2)
T2 patients (n = 26)	462	43	< 0.001a
Non-metastatic LNs	456 (98.7)	28 (65.1)
Metastatic LNs	6 (1.3)	15 (34.9)
T3 patients (n = 61)	1272	281	< 0.001a
Non-metastatic LNs	1226 (96.4)	257 (91.5)
Metastatic LNs	46 (3.6)	24 (8.5)
T4 patients (n = 10)	182	49	< 0.001a
Non-metastatic LNs	177 (97.3)	37 (75.5)
Metastatic LNs	5 (2.7)	12 (24.5)

^aP < 0.05.

LNs: Lymph nodes.

Table 4 The distribution of lymph nodes according to tumor locations

Variables	Staining (n = 146)	Non-staining (n = 146)	P value
Rectal cancer (n = 65)	1369	132	< 0.001a
Non-metastatic LNs	1346 (98.3)	104 (78.8)
Metastatic LNs	23 (1.7)	28 (21.2)
Sigmoid colon cancer (n = 52)	857	140	< 0.001a
Non-metastatic LNs	817 (95.3)	120 (85.7)
Metastatic LNs	40 (4.7)	20 (14.3)
Descending colon cancer (n = 14)	241	16	< 0.001a
Non-metastatic LNs	234 (97.1)	11 (68.8)
Metastatic LNs	7 (2.9)	5 (31.2)
Right colon cancer (n = 15)	322	135	0.218
Non-metastatic LNs	315 (97.8)	129 (95.6)
Metastatic LNs	7 (2.2)	6 (4.4)

^aP < 0.05.

LNs: Lymph nodes.

Table 5 Intra-operative characteristics and post-operative complications, mean ± SD/n (%)

Variables	Patients (n = 146)
Blood loss, mL	37.2 ± 24.1
Operative time, minute	139.5 ± 43.5
Complications	18 (12.3)
Abdominal infection	6
Bleeding	1
Ileus	3
Chylous leakage	5
Pulmonary infection	2
Urination disorder	1