1.

Clinical characteristics of patients and univariate analysis of prognostic factors

Characteristics	n	5-year LRFS (%)	P	5-year MMFS (%)	P	5-year PFS (%)	P	5-year OS (%)	P
LRFS, local progression-free survival; MMFS, multiple myeloma-free survival; PFS, progression-free survival; OS, overall survival; NA, not available; MM, multiple myeloma; RT, radiotherapy; CT, chemotherapy.
All patients	55	79.8		78.6		65.2		76.0
Age (year)
≥50	29	82.1	0.654	68.9	0.028	63.1	0.630	75.1	0.267
<50	26	77.2		91.7		67.9		76.6
Gender
Male	37	76.5	0.575	83.9	0.201	68.6	0.521	77.6	0.261
Female	18	86.7		68.2		58.4		72.8
Sites
Head and neck	39	91.8	0.004	89.6	0.003	75.9	0.026	77.4	0.625
Others	16	49.0		48.5		34.5		72.9
Tumor size (cm)
≥4	20	80.0	0.761	56.1	0.013	44.5	0.022	46.2	0.044
<4	35	79.5		88.1		75.0		89.0
Serum M protein
Positive	26	75.2	0.113	78.9	0.033	57.1	0.030	66.3	0.229
Negative	18	94.4		100		87.7		94.4
NA	11	64.0		45.7		41.1		59.3
Progression to MM
Present	10	–	–	–	–	–	–	45.7	0.021
Absent	45	–		–		–		87.4
Local recurrence
Present	12	–	–	48.9	0.001	–	–	56.8	0.358
Absent	43	–		88.5		–		84.1
RT
Yes	32	89.1	0.036	87.4	0.044	81.1	0.006	87.0	0.012
No	23	60.4		61.2		37.2		53.8
Surgery
Yes	29	80.2	0.320	74.8	0.102	55.1	0.055	81.0	0.620
No	26	80.4		82.9		75.7		73.0
CT
Yes	23	77.9	0.572	71.7	0.274	65.2	0.663	61.7	0.133
No	32	81.1		82.7		65.9		81.0