Pretreatment Prediction of Relapse Risk in Patients with Osteosarcoma Using Radiomics Nomogram Based on CT: A Retrospective Multicenter Study

Table 1

Clinical risk factors and CT-assessed candidate predictors of the patients.

Characteristic	Training cohort			Validation cohort
	Relapse	Nonrelapse		Relapse	Nonrelapse
Clinical risk factors
Patients	26 (41.3%)	37 (58.7%)		5 (29.4%)	12 (70.6%)	0.271^a
Sex (no. [%])			0.941^a			0.825^a
Male	15 (57.7%)	21 (56.8%)		4 (80.0%)	9 (75.0%)
Female	11 (42.3%)	16 (43.2%)		1 (20.0%)	3 (25.0%)
Age (years)			0.905^a			0.793^a
<30	24 (80.0%)	26 (78.8%)		3 (60.0%)	8 (66.7%)
≥30	6 (20.0%)	7 (21.2%)		2 (40.0%)	4 (33.3%)
Tumor location			0.253^a			0.119^a
Long bone	17 (65.4%)	29 (78.4%)		3 (60.0%)	11 (91.7%)
Flat bone	9 (34.6%)	8 (21.6%)		2 (40.0%)	1 (8.3%)
ALP (alkaline phosphatase) level (IU/L)			0.966^a			0.169^a
Normal	17 (65.4%)	24 (64.9%)		2 (40.0%)	9 (75.0%)
Abnormal	9 (34.6%)	13 (35.1%)		3 (60.0%)	3 (25.0%)
Hemoglobin level (mmol/L)			0.031^a			0.149^a
Normal	12 (46.2%)	27 (73.0%)		1 (20.0%)	7 (58.3%)
Abnormal	14 (53.8%)	10 (27.0%)		4 (80.0%)	5 (41.7%)
CT-assessed candidate predictors
Tumor volume (mm^3)			0.856^a			0.300^a
Surface			0.105^a			0.493^a
Size			0.765^a			0.978^a
Solidity			0.003^a			0.947^a
Eccentricity			0.275^a			0.343^a
Compactness			0.570^a			0.371^a
Sphericity			0.039^a			0.726^a
Support vector regression			0.169^a			0.529^a
Irregularity			0.011^a			0.941^a
Joint invasion			0.002^a			0.036^a
Yes	17 (65.4%)	10 (27.0%)		4 (80.0%)	3 (25.0%)
No	9 (34.6%)	27 (73.0%)		1 (20.0%)	9 (75.0%)
Pathologic fracture			0.184^a			0.253^a
Yes	4 (15.4%)	2 (5.4%)		0 (0.0%)	0 (0.0%)
No	22 (84.6%)	35 (94.6%)		5 (100.0%)	12 (100.0%)

value is less than 0.05. ^aChi-square test.