Table 1 Background parameters for the responders and study population

Region (n, (%))

South East

273 (70.2)

281 (69.7)

406 (68.6)

417 (67.1)

North

116 (29.8)

122 (30.3)

186 (31.4)

204 (32.9)

Sex (n, (%))

389 (49)

403 (51)

592 (49)

621 (51)

Age (mean)

65

59

64

59

Tumour site (n, (%))

Head/neck

54 (13.9)

33 (8.2)

79 (13.3)

54 (8.7)

Upper extremity

77 (19.8)

87 (21.6)

128 (21.6)

134 (21.6)

Lower extremity

50 (12.9)

145 (36)

69 (11.7)

207 (33.3)

Trunk

200 (51.4)

131 (32.5)

308 (52)

217 (34.9)

Hand, foot and subungual

4 (1)

6 (1.5)

4 (0.7)

8 (1.3)

Missing

4 (1)

1 (0.2)

4 (0.7)

1 (0.2)

Histopathological subtype (n, (%))

Superficial Spreading Melanoma

260 (66.8)

268 (66.5)

398 (67.2)

418 (67.3)

Lentigo Maligna Melanoma

17 (4.4)

14 (3.5)

28 (4.7)

23 (3.7)

Nodular Melanoma

50 (12.9)

57 (14.1)

75 (12.7)

86 (13.8)

Acral Lentiginous Melanoma

3 (0.8)

6 (1.5)

6 (1)

9 (1.4)

Other

51 (13.1)

45 (11.2)

66 (11.1)

65 (10.5)

Missing

8 (2.1)

13 (3.2)

19 (3.2)

20 (3.2)

Tumour thickness (n, (%))

<=1.00 mm

210 (54)

230 (57.1)

321 (54.2)

363 (58.5)

1.01-2.00 mm

92 (23.7)

81 (20.1)

136 (23)

111 (17.9)

2.01-4.00 mm

53 (13.6)

49 (12.2)

74 (12.5)

78 (12.6)

>4.00 mm

31 (8)

40 (9.9)

58 (9.8)

66 (10.6)

Missing

3 (0.8)

3 (0.7)

3 (0.5)

3 (0.5)

Tumour ulceration (n, (%))

Present

62 (15.9)

62 (15.4)

99 (16.7)

97 (15.6)

Absent

309 (79.4)

320 (79.4)

461 (77.9)

493 (79.4)

Missing

18 (4.6)

21 (5.2)

32 (5.4)

31 (5)

Stage (n, (%))

I

277 (71.2)

287 (71.2)

423 (71.5)

445 (71.7)

II

76 (19.5)

81 (20.1)

122 (20.6)

132 (21.3)

III –IV

33 (8.5)

30 (7.4)

42 (7.1)

39 (6.3)

Missing

3 (0.8)

5 (1.2)

5 (0.8)

5 (0.8)

Extended surgery of the primary tumour (n, (%))

Yes

344 (88.4)

362 (89.8)

509 (86)

542 (87.3)

No

35 (9)

37 (9.2)

71 (12)

70 (11.3)

Missing

10 (2.6)

4 (1)

12 (2)

9 (1.4)