Table 2.

Subgroup analysis of treatment outcome after stereotactic radiosurgery or radiotherapy for local failures of nasopharyngeal carcinoma

	3-year local failure-free rate			3-year overall survival rate
	SRS	SRM	p value	SRS	SRM	p value
Sex
male	54%	87%	0.006	63%	63%	0.806
female	42%	73%	0.275	75%	24%	0.067
Age
≤ 45	27%	87%	0.023	63%	44%	0.338
> 45	49%	80%	0.028	67%	62%	0.702
Type of failure
persistent disease	77%	94%	0.456	87%	90%	0.589
recurrent disease	30%	75%	0.001	52%	35%	0.419
rT stage
rT1	69%	88%	0.133	85%	79%	0.721
rT2-4	28%	78%	0.006	45%	28%	0.458
Tumor volume
≤ 5 cc	62%	90%	0.219	79%	75%	0.502
> 5 – 10 cc	61%	67%	0.342	78%	44%	0.117
> 10 cc	69%	84%	0.106	25%	52%	0.108

SRS: stereotactic radiotherapy using single fracton

SRM: stereotactic radiotherapy using multiple fractions