Table 3. Comparison of prognoses among different treatment methods.

	1			2		Median survival time (95% CI) (months)
	χ2	P		χ2	P
1	–	–		–	–	7 (4.867–9.133)
2	34.876	0.000		–	–	15 (13.658–16.342)
3	178.810	0.000		162.939	0.000	39 (33.669–44.331)

Note: 1, radiotherapy only; 2, radiotherapy + chemotherapy; 3, radiotherapy + chemotherapy + primary site surgery.