Table 2 Univariate analysis of factors affecting clinical outcome

Age (years)

   < 60

50.5

.653

27.6

.547

57.6

.084

   ≥60

47.9

36.2

75.9

Gender

   Male

55.6

.381

34.8

.340

73.7

.141

42.3

.811

   Female

34.9

27.7

55.7

38.1

Recurrence-free interval (months)

   <24

46.4

.675

33.2

.473

59.8

.248

40.6

.663

   ≥24

50.7

26.9

72.9

38.5

Previous recurrence history

   0

51.2

.417

36.4

.061

66.9

.834

43.0

.420

   1

38.8

16.7

65.2

33.0

Symptoms at recurrence

   Yes

26.3

.025

20.0

.007

40.0

.003

25.8

.047

   No

58.4

38.3

76.2

47.2

Recurrence site

   Central

56.0

.494

43.5

.429

67.7

.918

54.2

.305

   Lateral

44.8

26.0

69.1

31.5

   posterior

36.4

35.3

63.5

36.2

Pretreatment CEA (ng/mL)

   ≤5

45.7

.882

41.8

.071

72.1

.154

49.2

.458

   >5

52.8

21.8

59.1

33.8

Salvage Treatment

   Surgery + CRT

52.8

.181

35.2

.113

71.0

.379

43.6

.335

   CRT alone

40.6

24.5

55.9

34.6

Chemotherapy regimen

   Fluoropyrimidines-alone

47.3

.910

36.7

.572

67.2

.720

42.9

.562

   Irinotecan or Oxaliplatin -based

41.0

22.0

64.7

33.8

Resection§

   R0

60.4

.994

35.1

.956

77.7

.529

37.6

.919

   R1 or R2

42.9

34.3

65.6

46.8

Radiation dose (BED_2Gy)

   <60

46.9

.607

32.3

.281

78.2

.065

41.0

.694

   ≥60

48.3

29.2

52.9

39.2