Table 1. Clinicopathological characteristics of 1811 patients with NPC stratified by the presence or absence of parotid lymph node metastasis.

Characteristic	No. of 1790 patients (%) without PLN	No. of 21 patients (%) with PLN	P
Sex			0.24
Male	1333 (74.5%)	18 (85.7%)
Female	457 (25.5%)	3 (14.3%)
Age (years)			0.07
≤45	948 (53%)	7 (33.3%)
>45	842 (47%)	14 (66.7%)
Histological type			0.73
WHO type I	10 (0.6%)	0 (0%)
WHO type II/III	1780 (99.4%)	21 (100%)
Chemotherapy			0.06
No	259 (14.4%)	0 (0%)
Yes	1531 (85.6%)	21 (100%)
T-category			0.62
T1	323 (18%)	3 (14.3%)
T2	278 (15.5%)	5 (23.8%)
T3	857 (47.9%)	8 (38.1%)
T4	332 (18.5%)	5 (23.8%)
N-category			<0.01
N0	308 (17.2%)	0 (0%)
N1	1056 (59%)	6 (28.6%)
N2	271 (15.1%)	5 (23.8%)
N3a	30 (1.7%)	2 (9.5%)
N3b	125 (7%)	8 (38.1%)
Stage-group			<0.01
I	99 (5.5%)	0 (0%)
II	381 (21.3%)	1 (4.8%)
III	851 (47.5%)	6 (28.6%)
IVa	304 (17%)	4 (19%)
IVb	155 (8.7%)	10 (47.6%)