Table 4.

Effect of PMRT on OS and DFS in different risk groups

Group	RT	No.	5-y and 8-y OS(%)	HR(95%CI)	P
All(N = 596)	Yes	298	95.6/91.8	0.367(0.222–0.608)	<0.001
	No	298	89.5/78.9
Low-risk(N = 228)	Yes	113	100.0/97.9	0.306(0.084–1.114)	0.057
	No	115	96.5/91.6
Intermediate-risk(N = 164)	Yes	84	94.0/91.6	0.447(0.167–1.192)	0.099
	No	80	91.2/83.9
High-risk(N = 204)	Yes	101	92.1/87.7	0.340(0.175–0.661)	<0.001
	No	103	80.4/70.0

Group	RT	No.	5-y and 8-y DFS(%)	HR(95%CI)	P
All(N = 596)	Yes	298	91.3/85.6	0.476(0.320–0.707)	<0.001
	No	298	84.1/71.1
Low-risk(N = 157)	Yes	81	96.3/90.9	0.698(0.260–1.878)	0.475
	No	76	92.1/89.3
Intermediate-risk(N = 323)	Yes	161	90.1/87.7	0.572(0.337–0.970)	0.036
	No	162	86.3/77.8
High-risk(N = 116)	Yes	56	87.5/83.7	0.273(0.124–0.602)	<0.001
	No	60	68.3/56.1

Among the three risk groups based on OS nomgram. Low risk indicates a risk score ≤ 100, intermediate risk indicates a risk score of 100 to 149, and high risk indicates a risk score ≥ 149. Among the three risk groups based on OS nomgram. Low risk indicates a risk score <54, intermediate risk indicates a risk score of 54 to 123, and high risk indicates a risk score ≥ 123