Table 3.
Correlation of tumor volume, EBV DNA level with anatomic features of tumor spread
| Characteristics (primary and LNs) | Volume (cm3) (95% CI) † |
P |
pEBV DNA (copies/ml) (95% CI) | UVA P ‡ |
MVA P ‡ |
||
|---|---|---|---|---|---|---|---|
| + | - | + | - | ||||
| Nasal cavity | 30.0(22.3-34.5) | 16.3(14.1-18.7) | <0.001* | 616 (264-1438) | 417 (209-831) | 0.511 | NA |
| Oropharynx | 35.1(16.1-65.2) | 18.7(16.4-21.2) | 0.014* | 658 (184-2360) | 461 (261-812) | 0.549 | NA |
| Parapharyngeal space | 27.9(23.4-33.0) | 13.9(12.2-15.9) | <0.001* | 1340 (715-2513) | 201 (92-440) | 0.001* | NA |
| Prevertebral space | 25.8(21.9-30.0) | 13.6(11.5-16.0) | <0.001* | 646 (314-1330) | 329 (145-747) | 0.216 | NA |
| Skull base | 28.8(24.1-34.0) | 13.9(12.2-15.8) | <0.001* | 1196 (618-2314) | 233 (108-504) | 0.002* | 0.001* |
| Paranasal sinus | 41.1(33.7-49.5) | 17.3(15.2-19.6) | <0.001* | 732 (284-1883) | 443 (243-807) | 0.557 | NA |
| Masticator space | 36.1(29.2-43.9) | 15.6(13.8-17.7) | <0.001* | 856 (405-1810) | 382 (196-742) | 0.073 | NA |
| Intracranial region | 42.3(35.6-59.7) | 16.1(14.2-18.1) | <0.001* | 788 (332-1867) | 422 (225-791) | 0.236 | NA |
| Hypopharynx/Orbit/Parotid gland/Infratemporal fossa | 48.5(31.4-70.8) | 18.0(15.9-20.3) | <0.001* | 1576 (383-6484) | 433 (246-763) | 0.252 | NA |
| Retropharyngeal LNs | 11.2(8.2-14.8) | 1.8(0.4-4.4) | <0.001* | 1051 (613-1800) | 98 (34-281) | <0.001* | NA |
| Cervical metastasis | 11.5(8.7-14.7) | 0 | <0.001* | 1163 (721-1875) | 20 (7-59) | <0.001* | NA |
| Bilateral LNs | 19.7(15.0-25.3) | 2.9(1.5-4.8) | <0.001* | 2138 (1048-4359) | 196 (100-383) | <0.001* | NA |
| >6cm | 43.7(29.3-62.1) | 6.0(4.1-8.5) | <0.001* | 5651 (1407-22695) | 442 (256-764) | 0.003* | NA |
| Infracricoid LNs | 26.1(17.3-37.5) | 4.0(2.5-5.9) | <0.001* | 6412 (3423-12010) | 236 (133-419) | <0.001* | NA |
| Supraclavicular LNs | 18.1(2.5-59.3) | 6.3(4.2-8.8) | 0.086 | 18791(4901-72091) | 388 (228-661) | <0.001* | 0.001* |
| Extranodal spread | 25.5(21.0-30.6) | 2.0(1.1-3.3) | <0.001* | 2840 (1503-5366) | 172 (89-330) | <0.001* | NA |
| Central necrosis | 26.0(20.7-32.2) | 2.9(1.7-4.6) | <0.001* | 3859 (2172-6857) | 201 (107-376) | <0.001* | NA |
| Involved LN subregions≥4 | 19.5(15.3-24.5) | 1.5(0.7-2.7) | <0.001* | 3159 (1244-8024) | 256 (141-466) | <0.001* | NA |
* Statistically significant, P<0.05. † volume of primary tumor and LNs was respectively correlated to primary and LN characteristics. ‡ Both UVA and MVA were based on the natural logarithm of pEBV DNA level. LN, lymph node; NA, not applicable; pEBV DNA, plasma EBV DNA; UVA, univariate analysis; MVA, multivariate analysis.