A Study of 358 Cases of Locally Advanced Nasopharyngeal Carcinoma Receiving Intensity-Modulated Radiation Therapy: Improving the Seventh Edition of the American Joint Committee on Cancer T-Staging System

Table 6

Multivariate analysis of the nT-staging system.

Variable	Regression coefficient	Standard error	P value	HR	95% CI
					Low	Up
For OS
Age (<50 versus ≥50 years)	.731	.258	.005	2.077	1.253	3.444
New T category (nT3 versus nT4)	.918	.263	.000	2.504	1.496	4.190
N category (N0 versus N1 versus N2 versus N3)	.391	.137	.004	1.479	1.131	1.934
Sex (male versus female)	−.164	.278	.556	.849	.493	1.463
Pathologic type (WHO I versus II-III)	.397	.473	.401	1.488	.589	3.757
Chemotherapy (yes versus no)	−.400	.483	.407	.670	.260	1.728
Radiation dose (<73.92 versus ≥73.92 Gy)	−.202	.437	.644	.817	.347	1.924
For LRFS
Age (<50 versus ≥50 years)	1.759	.583	.003	5.806	1.853	18.197
New T category (nT3 versus nT4)	1.141	.538	.043	3.131	1.090	8.990
N category (N0 versus N1 versus N2 versus N3)	−.218	.270	.420	.804	.474	1.366
Sex (male versus female)	−.067	.587	.909	.935	.296	2.956
Pathologic type (WHO I versus II-III)	.462	.795	.561	1.587	.334	7.542
Chemotherapy (yes versus no)	.396	1.052	.707	1.486	.189	11.675
Radiation dose (<73.92 versus ≥73.92 Gy)	−.548	1.042	.599	.578	.075	4.456
For DMFS
Age (<50 versus ≥50 years)	.262	.281	.351	1.300	.749	2.255
New T category (nT3 versus nT4)	.932	.281	.001	2.539	1.463	4.404
N category (N0 versus N1 versus N2 versus N3)	.432	.149	.004	1.540	1.151	2.061
Sex (male versus female)	−.144	.301	.633	.866	.480	1.564
Pathologic type (WHO I versus II-III)	.220	.524	.675	1.246	.446	3.480
Chemotherapy (yes versus no)	−.184	.612	.763	.832	.251	2.759
Radiation dose (<73.92 versus ≥73.92 Gy)	−.056	.439	.899	.946	.400	2.237
For DFS
Age (<50 versus ≥50 years)	.510	.230	.026	1.666	1.062	2.613
New T category (nT3 versus nT4)	.861	.231	.000	2.365	1.504	3.719
N category (N0 versus N1 versus N2 versus N3)	.308	.120	.010	1.360	1.075	1.721
Sex (male versus female)	−.122	.250	.626	.885	.542	1.446
Pathological type (WHO I versus II-III)	.390	.400	.331	1.476	.674	3.236
Chemotherapy (yes versus no)	−.349	.439	.427	.705	.298	1.669
Radiation dose (<73.92 versus ≥73.92 Gy)	−.132	.378	.727	.876	.418	1.840

HR, hazard ratio; CI, confidence interval.