Table 4 Multivariate COX regression analysis comparing no recurrence and early recurrence

Number of mass

 1

Reference

 < 0.001

 2—7

1.43 (1.026 – 1.994)

0.035

  ≥ 8

2.266 (1.553 – 3.306)

 < 0.001

Mass size

  < 3 cm

Reference

  >  = 3 cm

1.08 (0.768 – 1.519)

0.657

Tumor shape

 Papillary

Reference

 Sessile/Flat erythematous

1.928 (1.284 – 2.894)

0.002

Resection depth

 Submucosa

Reference

0.615

 Muscle

1.576 (0.498 – 4.989)

0.439

 Perivesical fat

2.915 (0.296 – 28.699)

0.359

Complete TURB

 No

Reference

 Yes

0.338 (0.164 – 0.698)

0.003

Grade

 Low grade

Reference

 High grade

0.966 (0.722 – 1.291)

0.813

 CIS

1.005 (0.536 – 1.887)

0.987