Patterns and Prognostic Value of Lymph Node Metastasis on Distant Metastasis and Survival in Nasopharyngeal Carcinoma: A Surveillance, Epidemiology, and End Results Study, 2006–2015

Table 1

Comparison of clinicopathologic demographics between 2994 NPC patients according to LN involvement.

Characteristics	LN involvement^a
	N0 (n, %)	N1–3 (n, %)	Total number
Age group (years)
<40	66 (14.4)	393 (85.6)	459	<0.001
40–49	113 (17.6)	528 (82.4)	641
50–59	204 (23.1)	681 (76.9)	885
60–69	173 (28.7)	429 (71.3)	602
>70	139 (34.2)	268 (65.8)	407
Sex
Male	491 (23.0)	1648 (77.0)	2139	0.596
Female	204 (23.9)	651 (76.1)	855
Race^b
Asian/Pacific Islander	223 (19.8)	905 (80.2)	1128	0.002
White	369 (26.0)	1051 (74.0)	1420
Black	83 (22.4)	287 (77.6)	370
American Indian/Alaska Native	9 (17.3)	43 (82.7)	52
Histology
KSCC	320 (24.9)	966 (75.1)	1286	0.004
NKSCC	358 (21.5)	1307 (78.5)	1665
BSCC	17 (39.5)	26 (60.5)	43
T stage^c
T1 + T2	363 (22.5)	1247 (77.5)	1610	0.479
T3	146 (23.0)	488 (77.0)	634
T4	186 (24.8)	564 (75.2)	750
M stage
M0	655 (24.3)	2040 (75.7)	2695	<0.001
M1	40 (13.4)	259 (86.6)	299

BSCC, basaloid squamous cell carcinoma; LN, lymph node; KSCC, keratinizing squamous cell carcinoma; M, distant metastasis; N, node; NKSCC, nonkeratinizing carcinoma; T, tumor. ^aN0, none; N1, unilateral cervical and/or unilateral or bilateral retropharyngeal node(s), ≤6 cm in greatest dimension, above supraclavicular fossa; N2, bilateral cervical node(s), ≤6 cm in greatest dimension, above supraclavicular fossa; N3, N3a: >6 cm in greatest dimension, above supraclavicular fossa; N3b: in supraclavicular fossa. ^b24 cases were missing. ^cT1, nasopharynx, oropharynx, or nasal cavity; T2, parapharyngeal extension; T3, bony structures and/or paranasal sinuses; T4, intracranial extension and/or cranial nerves, hypopharynx, orbit, or infratemporal fossa/masticatory space.