Table 2.

Univariate and multivariate analysis of prognostic factors according to OS in thymoma

	OS	Univariate analysis		Multivariate analysis
Prognostic factors	n (%)	HR (95% CI)	P‐value	HR (95%CI)	P‐value
Tumor location (Superior/Inferior)	18 (66.7)/150 (89.8)	0.318 (0.142–0.715)	0.006*	0.371 (0.139–0.989)	0.048*
Age (continue)	‐	1.070 (1.034–1.107)	<0.001*	1.070 (1.034–1.107)	<0.001*
Tumor diameter (continue)	‐	1.087 (0.953–1.239)	0.215	‐	‐
Sex (Male/Female)	85 (86.7)/83 (86.5)	1.079 (0.499–2.333)	0.847	‐	‐
MG (Yes/No)	54 (84.4)/114 (87.7)	1.136 (0.514–2.510)	0.752	‐	‐
Anti‐AchR (positive/negative)§	53 (85.5)/115 (87.1)	1.008 (0.449–2.263)	0.985	‐	‐
WHO classification(A/AB/B1/B2/B3)†	14 (82.4)/43 (95.6)/57 (89.1)/40 (80.0)/14 (77.8)	1.403 (0.973–2.023)	0.070	1.093 (0.752–1.587)	0.641
Masaoka stage (I/II/III/IV)‡	87 (88.8)/49 (90.7)/18 (75.0)/14 (77.8)	1.541 (1.072–2.214)	0.019 *	1.277 (0.826–1.974)	0.272
MPMT (Yes/No)	21 (77.8)/147 (88.0)	2.218 (0.885–5.556)	0.089	1.894 (0.677–5.297)	0.224
Surgical radicality (R0/non‐R0)¶	153 (86.9)/15 (83.3)	2.179 (0.646–7.353)	0.209	‐	‐
Lymph node dissection (Yes/No)	34 (82.9)/134 (87.6)	1.454 (0.611–3.463)	0.397	‐	‐
Preoperative therapy (Yes/No)	5 (55.6)/163 (88.1)	5.387 (1.823–15.917)	0.002*	3.813 (1.143–12.724)	0.030*
Postoperative therapy (Yes/No)	65 (82.3)/103 (89.6)	1.395 (0.642–3.031)	0.400	‐	‐

^* P < 0.05.

^† Muller‐Hemelink et al., 1999.

^‡ Koga et al., 1994.

^§ Positive: The serum titer of Anti‐AchR ≥0.3nmol/L. Negative: The serum titer of Anti‐AchR<0.3nmol/L (Nakajima et al. 2008).

^¶ R0 resection: no residual tumor on microscopy; Non‐R0 resection: microscopic or macroscopic residual tumor.

OS, overall survival; HR, harzard ratio; CI, confidence interval; MG, myasthenia gravis; anti‐AchR, anti‐acetylcholine receptor; WHO, World Health Organization; MPMT, multiple primary malignant tumors.