Table 4. Cox-regression analysis of factors associated with OS in patients with PTSS.

	OS
Variable	HR (95%CI)	p value
Gender 1. Male 2. Female	0.81 (0.23–2.91)	0.75
Age 1. Less than 30 years 2. Greater than 30 years	1.48 (0.42–5.24)	0.53
Presence of metastases at baseline 1. Yes 2. No	0.18 (0.04–0.69)	0.01
ECOG PS 1. 0–1 2. More than 2	1.35 (0.37–4.9)	0.65
Size of tumour 1. Less than 10 cm 2. Greater than 10 cm	0.41 (0.09–1.79)	0.24
Primary site 1. Pulmonary 2. Non-pulmonary	1.07 (0.29–3.96)	0.91
Lymph node involvement 1. Positive 2. Negative	2.27 (0.48–10.63)	0.29
Surgery performed 1. Yes 2. No	6.60 (1.79–24.39)	0.005
Surgical resection status 1. Complete microscopic resection 2. Microscopic/gross residual disease	1.17 (0.39–3.56)	0.77
Administration of RT 1. Yes 2. No	1.26 (0.50–3.17)	0.61
Administration of adjuvant chemotherapy 1. Yes 2. No	1.46 (0.28–7.39)	0.63

PTSS: Primary thoracic synovial sarcoma, OS: Overall Survival, ECOG PS: Eastern

Co-operative Oncology Group Performance Status