Logistic regression analysis of pathological features of bone metastasis in colorectal cancer and related influencing factors after surgery

Table 1 Pathological characteristics of postoperative bone metastases in patients undergoing colorectal cancer surgery

Items		Cases (n = 44)	Proportion, %
Age, years	54.33 ± 8.45
Sex	Male	24	54.55
	Female	20	45.45
The primary location of the tumor	Colon	11	25.00
	Rectum	33	75.00
Tumor diameter, cm	4.02 ± 1.02
Osteopathic changes	Osteolytic	19	43.18
	Osteogenic	14	31.82
	Mixed bone destruction	11	25.00
Type of bone metastasis	Single type	15	34.09
	Multiple type	29	65.91
Infiltration depth	T1-T2	14	31.82
	T3-T4	30	68.18
Lymphatic metastasis	Yes	29	65.91
	No	15	34.09
Location of bone metastases	Skull	8	18.18
	Pelvis	18	40.91
	Trunk	6	13.64
	Four limbs	5	11.36
	Spinal column	7	15.91
Bone metastasis organs	Liver	11	25.00
	Lung	26	59.09
	Pancreas	7	15.91

Table 2 Single variables affecting the occurrence of postoperative bone metastases in patients undergoing colorectal cancer surgery, n (%)

Variables		Bone metastases (n = 44)	No bone metastases (n = 56)	t/χ2	P value
Age	≤ 60	24 (54.55)	36 (64.29)	0.974	0.324
	> 60	20 (45.45)	20 (42.86)
Sex	Male	24 (54.55)	40 (71.43)	3.048	0.081
	Female	20 (45.45)	16 (28.57)
The primary location of the tumor	Colon	11 (25.00)	30 (53.57)	8.315	0.004
	Rectum	33 (75.00)	26 (46.43)
Tumor diameter	< 5 cm	31 (70.45)	34 (60.71)	1.028	0.311
	≥ 5 cm	13 (29.55)	22 (39.29)
Osteopathic changes	Osteolytic	19 (43.18)	15 (26.79)	2.985	0.225
	Osteogenic	14 (31.82)	22 (39.29)
	Mixed bone destruction	11 (25.00)	19 (33.93)
Infiltration depth	T1-T2	14 (31.82)	27 (48.21)	2.738	0.098
	T3-T4	30 (68.18)	29 (51.79)
Postoperative chemotherapy	Yes	11 (25.00)	45 (80.36)	30.644	< 0.001
	No	33 (75.00)	11 (19.64)
Combined lung metastases	Yes	26 (59.09)	18 (32.14)	7.262	0.007
	No	18 (40.91)	38 (67.86)
Concomitant liver metastasis	Yes	11 (25.00)	24 (42.86)	3.454	0.063
	No	33 (75.00)	32 (57.14)
Concomitant pancreatic metastasis	Yes	7 (15.91)	11 (19.64)	0.233	0.630
	No	37 (84.09)	45 (80.36)
Lymph node involvement	Yes	29 (65.91)	19 (33.93)	10.096	0.002
	No	15 (34.09)	37 (66.07)

Table 3 Variable assignments

Independent variable	Assignment
The primary location of the tumor	“rectum” = 1, “colon” = 0
Lymph node involvement	“yes” = 1, “no” = 0
Pulmonary metastasis	“yes” = 1, “no” = 0
Postoperative chemotherapy	“yes” = 1, “no” = 0

Table 4 Multiple logistic regression models analyzed the risk factors affecting postoperative bone metastasis in patients undergoing colorectal cancer surgery

Factor	Partial regression coefficient	SE	Wald	OR	95%CI	P value
The primary location of the tumor was a rectal cancer	1.128	0.322	17.527	2.456	1.644-3.674	< 0.001
With combined lymph node involvement	1.144	0.311	10.214	2.024	1.159-3.654	< 0.001
Combined lung metastases	1.134	0.241	14.327	3.124	2.124-5.544	< 0.001
No chemotherapy was administered after surgery	1.412	0.224	21.236	3.544	1.664-6.922	< 0.001

OR: Odds ratio; CI: Confidence interval.