Overview

The design of these tables is based on our research meeting with Dr. Shields on 6/2/2022. The current N for all FST tables (924) is correct given that 77 patients currently have no data for their Fitzpatrick Scale. The tables are a little crowded right now because I included results for patients with missing Fitzpatrick values and there is only a single person with FST Type V. Hopefully as we continue to gather FST data the missing column can be removed and more people will be found for the FST Type V category.

There is quite a lot to customize with the package I’m using to make these tables, so let me know if you’d like to switch up the order, change the spacing, or include different variables and I’ll try to figure it out!

Table 1

Demographics by FST (with P-values)

Table 1. Demographics by Fitzpatrick Scale
Demographics Overall, N = 9241 Fitzpatrick (FST) Scale p-value2
Missing
N = 227 (25%)1
FST Type I
N = 44 (4.8%)1
FST Type II
N = 610 (66%)1
FST Type III
N = 34 (3.7%)1
FST Type IV
N = 8 (0.9%)1
FST Type V
N = 1 (0.1%)1
Patient Age <0.001
Mean (SD) 58 (14) 58 (14) 61 (14) 58 (14) 50 (14) 47 (12) 23 (NA)
Median (IQR) 60 (50, 68) 59 (48, 69) 62 (53, 69) 60 (51, 69) 53 (37, 60) 50 (36, 54) 23 (23, 23)
Range 10, 94 14, 92 29, 94 10, 90 19, 75 28, 65 23, 23
Sex 0.7
Male 479 (52%) 113 (50%) 21 (48%) 319 (52%) 21 (62%) 5 (62%) 0 (0%)
Female 445 (48%) 114 (50%) 23 (52%) 291 (48%) 13 (38%) 3 (38%) 1 (100%)
Melanocytosis 0.7
No 842 (97%) 209 (98%) 41 (98%) 554 (97%) 30 (91%) 7 (100%) 1 (100%)
Yes 29 (3.3%) 5 (2.3%) 1 (2.4%) 20 (3.5%) 3 (9.1%) 0 (0%) 0 (0%)
Heterochromia 0.072
No 855 (98%) 214 (100%) 41 (98%) 562 (98%) 30 (91%) 7 (100%) 1 (100%)
Yes 16 (1.8%) 0 (0%) 1 (2.4%) 12 (2.1%) 3 (9.1%) 0 (0%) 0 (0%)
Study Eye
Right Eye 468 (53%) 122 (54%) 22 (52%) 302 (52%) 19 (58%) 2 (29%) 1 (100%)
Left Eye 418 (47%) 105 (46%) 20 (48%) 274 (48%) 14 (42%) 5 (71%) 0 (0%)
Visual Acuity
20/20-20/50 685 (74%) 173 (76%) 32 (73%) 453 (74%) 23 (68%) 4 (50%) 0 (0%)
20/60-20/200 152 (16%) 38 (17%) 3 (6.8%) 102 (17%) 6 (18%) 3 (38%) 0 (0%)
20/400-NLP 87 (9.4%) 16 (7.0%) 9 (20%) 55 (9.0%) 5 (15%) 1 (12%) 1 (100%)
1 n (%)
2 Kruskal-Wallis rank sum test; Fisher's exact test

Tables 2 (A and B)

A) Clinical Features by FST

Table 2A. Clinical Features by Fitzpatrick Scale
Clinical Features Overall, N = 9241 Fitzpatrick (FST) Scale p-value2
Missing
N = 227 (25%)1
FST Type I
N = 44 (4.8%)1
FST Type II
N = 610 (66%)1
FST Type III
N = 34 (3.7%)1
FST Type IV
N = 8 (0.9%)1
FST Type V
N = 1 (0.1%)1
Distance to optic disc (mm) 0.050
Mean (SD) 4.6 (4.2) 3.9 (3.6) 4.9 (4.1) 4.8 (4.4) 4.2 (4.7) 7.1 (4.7) 0.0 (NA)
Median (IQR) 3.7 (1.0, 7.0) 3.0 (1.0, 6.0) 4.5 (1.8, 7.0) 4.0 (1.0, 7.0) 3.0 (0.0, 6.0) 5.0 (4.5, 8.0) 0.0 (0.0, 0.0)
Range 0.0, 20.0 0.0, 16.0 0.0, 15.0 0.0, 20.0 0.0, 16.0 3.0, 17.0 0.0, 0.0
Unknown 54 1 4 46 2 1 0
Distance to foveola (mm) <0.001
Mean (SD) 4.3 (4.2) 3.5 (3.7) 5.4 (3.9) 4.6 (4.4) 4.0 (5.0) 5.9 (3.9) 0.0 (NA)
Median (IQR) 3.0 (1.0, 6.5) 2.0 (0.0, 6.0) 5.0 (3.0, 7.6) 3.0 (1.0, 7.0) 2.2 (0.0, 6.0) 5.0 (4.0, 6.0) 0.0 (0.0, 0.0)
Range 0.0, 18.4 0.0, 16.5 0.0, 17.0 0.0, 18.4 0.0, 17.0 2.0, 14.0 0.0, 0.0
Unknown 55 1 4 47 2 1 0
Largest basal diameter (mm) 0.006
Mean (SD) 12.2 (4.4) 11.7 (4.1) 14.2 (4.3) 12.2 (4.4) 12.2 (4.7) 15.2 (4.1) 17.0 (NA)
Median (IQR) 12.0 (9.0, 16.0) 11.0 (9.0, 14.0) 15.5 (10.0, 16.2) 12.0 (9.0, 16.0) 12.5 (8.2, 16.0) 15.5 (14.2, 18.2) 17.0 (17.0, 17.0)
Range 1.0, 24.0 4.0, 22.0 6.0, 24.0 1.0, 24.0 3.5, 20.0 7.0, 19.2 17.0, 17.0
Thickness at DFS (mm) <0.001
Mean (SD) 5.7 (3.3) 4.7 (2.4) 7.4 (4.0) 5.9 (3.4) 6.1 (3.7) 8.3 (3.2) 4.7 (NA)
Median (IQR) 4.7 (3.0, 7.8) 3.9 (3.0, 5.8) 6.6 (4.7, 9.4) 5.0 (3.0, 8.2) 4.7 (2.9, 8.8) 9.2 (5.2, 10.9) 4.7 (4.7, 4.7)
Range 0.7, 20.4 1.3, 13.3 2.2, 20.4 0.7, 15.3 1.4, 16.0 3.7, 12.0 4.7, 4.7
Thickness at DLS (mm) <0.001
Mean (SD) 3.19 (1.99) 2.82 (1.50) 3.90 (3.08) 3.19 (1.93) 4.06 (2.70) 6.91 (3.41) 6.50 (NA)
Median (IQR) 2.60 (1.90, 3.80) 2.40 (1.80, 3.60) 3.30 (2.25, 4.40) 2.65 (2.00, 3.80) 2.95 (2.28, 5.53) 8.20 (3.95, 9.25) 6.50 (6.50, 6.50)
Range 0.00, 19.80 1.00, 9.10 1.50, 19.80 0.00, 15.30 1.12, 12.00 2.70, 11.10 6.50, 6.50
Unknown 94 4 5 82 2 1 0
Change in thickness (DLS-DFS 0.005
Mean (SD) -2.17 (2.23) -1.80 (1.79) -2.97 (2.50) -2.32 (2.34) -1.69 (1.88) -1.39 (3.39) 1.80 (NA)
Median (IQR) -1.50 (-3.38, -0.50) -1.30 (-2.40, -0.60) -2.90 (-4.35, -1.15) -1.60 (-3.60, -0.60) -1.00 (-3.33, -0.30) -0.90 (-1.80, 0.00) 1.80 (1.80, 1.80)
Range -13.50, 5.10 -10.50, 1.20 -8.90, 2.10 -13.50, 5.10 -6.30, 0.00 -8.10, 2.90 1.80, 1.80
Unknown 94 4 5 82 2 1 0
Percent change in thickness (DLS-DFS/DFS) 0.007
Mean (SD) -0.35 (0.27) -0.35 (0.22) -0.39 (0.31) -0.35 (0.29) -0.26 (0.21) -0.11 (0.39) 0.38 (NA)
Median (IQR) -0.36 (-0.54, -0.18) -0.35 (-0.53, -0.19) -0.43 (-0.58, -0.29) -0.37 (-0.55, -0.18) -0.21 (-0.39, -0.11) -0.08 (-0.26, 0.00) 0.38 (0.38, 0.38)
Range -1.00, 2.12 -0.88, 0.26 -0.76, 0.81 -1.00, 2.12 -0.83, 0.00 -0.74, 0.55 0.38, 0.38
Unknown 94 4 5 82 2 1 0
Tumor epicenter
Choroid 838 (91%) 220 (97%) 40 (91%) 539 (89%) 32 (94%) 6 (75%) 1 (100%)
Ciliary Body 68 (7.4%) 7 (3.1%) 4 (9.1%) 53 (8.7%) 2 (5.9%) 2 (25%) 0 (0%)
Iris 16 (1.7%) 0 (0%) 0 (0%) 16 (2.6%) 0 (0%) 0 (0%) 0 (0%)
1 n (%)
2 Kruskal-Wallis rank sum test

B) Clinical Features by TCGA

Table 2B. Clinical Features by TCGA
Clinical Features Overall, N = 1,0011 TCGA Classification p-value2
Missing
N = 1 (<0.1%)1
Group A
N = 485 (48%)1
Group B
N = 141 (14%)1
Group C
N = 260 (26%)1
Group D
N = 114 (11%)1
Distance to optic disc (mm) <0.001
Mean (SD) 4.5 (4.1) 8.0 (NA) 3.9 (3.9) 4.7 (4.1) 5.5 (4.3) 4.9 (4.3)
Median (IQR) 3.5 (1.0, 7.0) 8.0 (8.0, 8.0) 3.0 (0.5, 5.8) 4.0 (1.0, 6.6) 5.0 (2.0, 8.0) 5.0 (0.0, 8.0)
Range 0.0, 20.0 8.0, 8.0 0.0, 20.0 0.0, 18.0 0.0, 17.0 0.0, 18.0
Unknown 55 0 22 9 17 7
Distance to foveola (mm) <0.001
Mean (SD) 4.3 (4.2) 8.0 (NA) 3.6 (3.9) 4.1 (3.7) 5.4 (4.6) 4.7 (4.3)
Median (IQR) 3.0 (1.0, 6.0) 8.0 (8.0, 8.0) 2.0 (0.3, 5.8) 3.2 (1.0, 6.0) 4.0 (2.0, 8.3) 3.0 (1.0, 8.0)
Range 0.0, 18.4 8.0, 8.0 0.0, 18.4 0.0, 15.0 0.0, 18.0 0.0, 17.0
Unknown 56 0 22 9 17 8
Largest basal diameter (mm) <0.001
Mean (SD) 12.1 (4.4) 8.0 (NA) 10.5 (3.9) 12.7 (4.5) 13.6 (4.1) 15.3 (3.5)
Median (IQR) 12.0 (9.0, 16.0) 8.0 (8.0, 8.0) 10.0 (8.0, 13.0) 13.0 (9.0, 16.0) 14.0 (10.0, 16.0) 16.0 (14.0, 18.0)
Range 1.0, 24.0 8.0, 8.0 1.0, 22.0 2.0, 22.0 2.0, 24.0 6.0, 24.0
Thickness at DFS (mm) <0.001
Mean (SD) 5.6 (3.3) 5.5 (NA) 4.4 (2.5) 6.2 (3.5) 6.7 (3.4) 7.6 (3.4)
Median (IQR) 4.7 (3.0, 7.7) 5.5 (5.5, 5.5) 3.5 (2.5, 5.5) 5.2 (3.2, 9.0) 6.0 (4.0, 9.2) 7.0 (4.5, 10.0)
Range 0.7, 20.4 5.5, 5.5 1.0, 14.1 1.3, 15.0 0.7, 16.0 2.1, 20.4
Thickness at DLS (mm) <0.001
Mean (SD) 3.19 (1.99) 2.70 (NA) 2.64 (1.41) 3.46 (2.21) 3.86 (2.31) 3.82 (2.44)
Median (IQR) 2.60 (1.90, 3.80) 2.70 (2.70, 2.70) 2.30 (1.70, 3.10) 2.70 (2.00, 4.15) 3.30 (2.20, 4.88) 3.40 (2.50, 4.20)
Range 0.00, 19.80 2.70, 2.70 0.80, 12.00 0.80, 12.50 0.00, 15.30 1.30, 19.80
Unknown 169 0 72 26 50 21
Change in thickness (DLS-DFS <0.001
Mean (SD) -2.17 (2.23) -2.80 (NA) -1.57 (1.68) -2.40 (2.48) -2.74 (2.60) -3.27 (2.35)
Median (IQR) -1.50 (-3.33, -0.50) -2.80 (-2.80, -2.80) -1.10 (-2.20, -0.40) -1.70 (-3.85, -0.75) -2.25 (-4.00, -0.90) -2.80 (-5.10, -1.50)
Range -13.50, 5.10 -2.80, -2.80 -8.20, 1.70 -10.70, 5.10 -13.50, 2.90 -8.30, 1.50
Unknown 169 0 72 26 50 21
Percent change in thickness (DLS-DFS/DFS) <0.001
Mean (SD) -0.35 (0.27) -0.51 (NA) -0.31 (0.25) -0.35 (0.36) -0.37 (0.27) -0.44 (0.24)
Median (IQR) -0.36 (-0.54, -0.18) -0.51 (-0.51, -0.51) -0.33 (-0.48, -0.16) -0.41 (-0.59, -0.18) -0.38 (-0.57, -0.20) -0.49 (-0.60, -0.31)
Range -1.00, 2.12 -0.51, -0.51 -0.85, 1.31 -0.77, 2.12 -1.00, 0.81 -0.84, 0.45
Unknown 169 0 72 26 50 21
Tumor epicenter
Choroid 914 (91%) 1 (100%) 458 (94%) 126 (90%) 226 (87%) 103 (90%)
Ciliary Body 68 (6.8%) 0 (0%) 20 (4.1%) 11 (7.9%) 26 (10%) 11 (9.6%)
Iris 17 (1.7%) 0 (0%) 7 (1.4%) 3 (2.1%) 7 (2.7%) 0 (0%)
1 n (%)
2 Kruskal-Wallis rank sum test

Table 3

Clinical Treatment/Management by FST

Table 3. Clinical Treatment/Management by Fitzpatrick Scale
Clinical Treatment/Management Overall, N = 9241 Fitzpatrick (FST) Scale p-value2
Missing
N = 227 (25%)1
FST Type I
N = 44 (4.8%)1
FST Type II
N = 610 (66%)1
FST Type III
N = 34 (3.7%)1
FST Type IV
N = 8 (0.9%)1
FST Type V
N = 1 (0.1%)1
Time from DFS to date of treatment (mons) 0.12
Mean (SD) 1.58 (8.91) 1.21 (7.49) 0.48 (1.21) 1.88 (9.95) 0.32 (0.65) 0.64 (0.81) 3.83 (NA)
Median (IQR) 0.10 (0.10, 0.33) 0.10 (0.10, 0.33) 0.10 (0.10, 0.33) 0.10 (0.10, 0.33) 0.10 (0.07, 0.33) 0.45 (0.10, 0.63) 3.83 (3.83, 3.83)
Range -28.43, 122.07 -8.37, 97.10 0.00, 6.63 -28.43, 122.07 -0.03, 3.60 0.10, 2.53 3.83, 3.83
Treatment
Plaque 705 (76%) 147 (65%) 28 (64%) 497 (82%) 26 (76%) 6 (75%) 1 (100%)
Plaque and TTT 149 (16%) 71 (31%) 10 (23%) 60 (9.9%) 6 (18%) 2 (25%) 0 (0%)
Plaque and PDT 9 (1.0%) 5 (2.2%) 2 (4.5%) 2 (0.3%) 0 (0%) 0 (0%) 0 (0%)
Enucleation 56 (6.1%) 4 (1.8%) 4 (9.1%) 46 (7.6%) 2 (5.9%) 0 (0%) 0 (0%)
PLSU 2 (0.2%) 0 (0%) 0 (0%) 2 (0.3%) 0 (0%) 0 (0%) 0 (0%)
Stereotactic Radiatio, 1 (0.1%) 0 (0%) 0 (0%) 1 (0.2%) 0 (0%) 0 (0%) 0 (0%)
No Follow up after FNAB 1 (0.1%) 0 (0%) 0 (0%) 1 (0.2%) 0 (0%) 0 (0%) 0 (0%)
Observation 0 (0%) 0 (0%) 0 (0%) 0 (0%) 0 (0%) 0 (0%) 0 (0%)
Fine Needle Aspiration Biopsy (FNAB) >0.9
No 2 (0.2%) 0 (0%) 0 (0%) 2 (0.3%) 0 (0%) 0 (0%) 0 (0%)
Yes 922 (100%) 227 (100%) 44 (100%) 608 (100%) 34 (100%) 8 (100%) 1 (100%)
Route of FNAB
Not done 4 (0.4%) 0 (0%) 1 (2.3%) 3 (0.5%) 0 (0%) 0 (0%) 0 (0%)
Trans-scleral 244 (27%) 49 (22%) 17 (39%) 164 (27%) 8 (24%) 5 (62%) 1 (100%)
Pars Plana 598 (65%) 171 (76%) 22 (50%) 379 (63%) 23 (70%) 3 (38%) 0 (0%)
Clear Cornea 22 (2.4%) 1 (0.4%) 1 (2.3%) 20 (3.3%) 0 (0%) 0 (0%) 0 (0%)
Enucleation 49 (5.3%) 4 (1.8%) 3 (6.8%) 40 (6.6%) 2 (6.1%) 0 (0%) 0 (0%)
Cells Visible
No 185 (21%) 64 (31%) 10 (24%) 104 (18%) 6 (18%) 1 (12%) 0 (NA%)
Yes 682 (79%) 142 (69%) 31 (76%) 475 (82%) 27 (82%) 7 (88%) 0 (NA%)
1 n (%)
2 Kruskal-Wallis rank sum test; Fisher's exact test

Table 4

Outcomes by FST

Table 4. Outcomes by Fitzpatrick Scale
Outcomes Overall, N = 9241 Fitzpatrick (FST) Scale p-value2
Missing
N = 227 (25%)1
FST Type I
N = 44 (4.8%)1
FST Type II
N = 610 (66%)1
FST Type III
N = 34 (3.7%)1
FST Type IV
N = 8 (0.9%)1
FST Type V
N = 1 (0.1%)1
Follow-up period (mons) 0.008
Mean (SD) 42 (35) 37 (34) 36 (29) 45 (36) 38 (38) 42 (41) 4 (NA)
Median (IQR) 32 (17, 62) 27 (9, 57) 33 (17, 42) 34 (20, 67) 25 (12, 62) 44 (16, 46) 4 (4, 4)
Range 0, 210 0, 210 1, 111 0, 198 0, 154 0, 124 4, 4
Unknown 43 2 3 36 1 1 0
Local Recurrence 0.033
No 854 (97%) 219 (98%) 40 (98%) 558 (97%) 30 (94%) 6 (86%) 1 (100%)
Yes 26 (3.0%) 5 (2.2%) 1 (2.4%) 17 (3.0%) 2 (6.2%) 1 (14%) 0 (0%)
Vision Loss
No 400 (45%) 123 (55%) 20 (48%) 237 (41%) 15 (45%) 4 (57%) 1 (100%)
Yes 483 (55%) 102 (45%) 22 (52%) 338 (59%) 18 (55%) 3 (43%) 0 (0%)
Death
No 825 (94%) 211 (93%) 34 (83%) 541 (94%) 31 (97%) 7 (100%) 1 (100%)
Yes 57 (6.5%) 15 (6.6%) 7 (17%) 34 (5.9%) 1 (3.1%) 0 (0%) 0 (0%)
Death from malignant melanoma 0.2
No 43 (77%) 11 (65%) 6 (86%) 25 (81%) 1 (100%) 0 (NA%) 0 (NA%)
Yes 13 (23%) 6 (35%) 1 (14%) 6 (19%) 0 (0%) 0 (NA%) 0 (NA%)
1 n (%)
2 Kruskal-Wallis rank sum test; Fisher's exact test

Tables 5 (A, B and C)

A) Univariate Analysis

Table 5A. Metastasis by Fitzpatrick Scale
Outcomes Overall, N = 9241 Fitzpatrick (FST) Scale p-value2
Missing
N = 227 (25%)1
FST Type I
N = 44 (4.8%)1
FST Type II
N = 610 (66%)1
FST Type III
N = 34 (3.7%)1
FST Type IV
N = 8 (0.9%)1
FST Type V
N = 1 (0.1%)1
Metastasis
No 726 (82%) 190 (85%) 27 (66%) 472 (82%) 29 (91%) 7 (100%) 1 (100%)
Yes 154 (18%) 34 (15%) 14 (34%) 103 (18%) 3 (9.4%) 0 (0%) 0 (0%)
Location of Metastasis >0.9
Liver metastasis 120 (78%) 28 (82%) 10 (71%) 80 (78%) 2 (67%) 0 (NA%) 0 (NA%)
Lung metastasis 4 (2.6%) 1 (2.9%) 0 (0%) 3 (2.9%) 0 (0%) 0 (NA%) 0 (NA%)
Liver and lung metastasis 26 (17%) 3 (8.8%) 4 (29%) 19 (19%) 0 (0%) 0 (NA%) 0 (NA%)
Other metastasis 3 (2.0%) 2 (5.9%) 0 (0%) 0 (0%) 1 (33%) 0 (NA%) 0 (NA%)
1 n (%)
2 Fisher's exact test

B) Univariate Binomial Regression

Interpretation: as the Fitzpatrick scale increases (i.e. as skin color becomes darker), the odds of metastasis decrease!
Table 5B. Univariate Regression of Metastasis based on Fitzpatrick Scale
Metastasis N Event N1 OR2 95% CI2 p-value q-value3
Fitzpatrick (FST) Scale 648 0.020 0.020
FST Type I 14
FST Type II 103 0.42 0.22, 0.85
FST Type III 3 0.20 0.04, 0.69
1 There were no instances of metastasis for FST types IV and V
2 OR = Odds Ratio, CI = Confidence Interval
3 False discovery rate correction for multiple testing

C) Multivariate Regression

Adjustments will be made for: age, tumor largest diameter, and thickness

I will try both Poisson and Binomial distributions for the glm link function (not sure which one is more accurate). A binomial logistic regression was used in the Genetic Analysis of Uveal Melanoma paper from 2019.

Explanation of when to use Poisson versus Binomial from stackexchange:

"If your outcome is discrete, or more precisely, you are dealing with counts (how many times something happen in given time interval),then the most common choice of the distribution to start with is Poisson distribution. The problem with Poisson distribution is that it is rather inflexible in the fact that it assumes that mean is equal to variance, if this assumption is not met, you may consider using quasi-Poisson family, or negative binomial distribution (see also Definition of dispersion parameter for quasipoisson family).

If your outcome is binary (zeros and ones), proportions of “successes” and “failures” (values between 0 and 1), or their counts, you can use Binomial distribution, i.e. the logistic regression model. If there is more then two categories, you would use multinomial distribution in multinomial regression."

C.1) Poisson

Interpretation: FST becomes less of a protective factor for metastasis as adjustments for age, largest basal diameter, and thickness DLS are made.

Table 5C.1. Staged, Multivariate Regression of Metastasis (Poisson)
Characteristic Metastasis ~ FST Metastasis ~ FST + Age Metastasis ~ FST + Age + Largest Basal Diameter Metastasis ~ FST + Age + Largest Basal Diameter + Thickness DLS
IRR1 95% CI1 p-value2 IRR1 95% CI1 p-value2 IRR1 95% CI1 p-value2 IRR1 95% CI1 p-value2
Fitzpatrick (FST) Scale 0.52 0.33, 0.87 0.010 0.55 0.34, 0.93 0.020 0.69 0.43, 1.13 0.13 0.66 0.40, 1.12 0.11
Age 1.02 1.00, 1.03 0.035 1.01 1.00, 1.02 0.2 1.02 1.00, 1.03 0.042
Largest Basal Diameter (mm) 1.18 1.13, 1.24 <0.001 1.24 1.17, 1.32 <0.001
Thickness DLS (mm) 0.97 0.89, 1.04 0.4
1 IRR = Incidence Rate Ratio, CI = Confidence Interval
2 Statistically significant P-values (<0.05) emboldened

C.2) Binomial

Interpretation: Similar trends to the Poisson regressions. FST become less of a protective factor for metastasis when adjustments for age, largest basal diameter, and thickness DLS are made.

Table 5C.2. Staged, Multivariate Regression of Metastasis (Binomial)
Characteristic Metastasis ~ FST Metastasis ~ FST + Age Metastasis ~ FST + Age + Largest Basal Diameter Metastasis ~ FST + Age + Largest Basal Diameter + Thickness DLS
OR1 95% CI1 p-value2 OR1 95% CI1 p-value2 OR1 95% CI1 p-value2 OR1 95% CI1 p-value2
Fitzpatrick (FST) Scale 0.43 0.24, 0.78 0.005 0.46 0.25, 0.84 0.011 0.54 0.29, 1.00 0.052 0.53 0.27, 1.03 0.063
Age 1.02 1.00, 1.03 0.020 1.01 1.00, 1.03 0.070 1.02 1.00, 1.04 0.017
Largest Basal Diameter (mm) 1.26 1.19, 1.33 <0.001 1.34 1.24, 1.44 <0.001
Thickness DLS (mm) 0.97 0.87, 1.08 0.6
1 OR = Odds Ratio, CI = Confidence Interval
2 Statistically significant P-values (<0.05) emboldened

Survival Analysis

Table 6

Table 6. Adjusted Hazard Ratios of Metastasis and Death for FST and Relevant Covariates
Characteristic Metastasis Death
HR1 95% CI1 p-value HR1 95% CI1 p-value
FST 1.07 0.58, 1.99 0.8 1.02 0.30, 3.43 >0.9
Age 1.03 1.01, 1.05 0.001 1.04 1.01, 1.08 0.022
Largest Basal Diameter 1.01 0.94, 1.07 0.9 0.94 0.82, 1.08 0.4
Thickness DLS (mm) 1.22 1.09, 1.37 <0.001 1.32 1.03, 1.70 0.030
1 HR = Hazard Ratio, CI = Confidence Interval

Risk of and Survival Probability of Metastasis

Risk of and Survival Probability of Death

Log-Rank Tests and Cox Models for Metastasis

#Log-rank test: difference between the survival curves for metastasis
survival::survdiff(Surv(time_till_mets_new, mets_new) ~ fst, data=data_survival)
## Call:
## survival::survdiff(formula = Surv(time_till_mets_new, mets_new) ~ 
##     fst, data = data_survival)
## 
## n=112, 576 observations deleted due to missingness.
## 
##        N Observed Expected (O-E)^2/E (O-E)^2/V
## fst=1 13       13     15.2    0.3172    0.3741
## fst=2 97       97     95.1    0.0378    0.2564
## fst=3  2        2      1.7    0.0524    0.0536
## 
##  Chisq= 0.4  on 2 degrees of freedom, p= 0.8
# Traditional adjustment for confounders is to use a Cox model and estimate hazard ratio
# Unadjusted Cox model
survival::coxph(Surv(time_till_mets_new, mets_new) ~ fst, data = data_survival)
## Call:
## survival::coxph(formula = Surv(time_till_mets_new, mets_new) ~ 
##     fst, data = data_survival)
## 
##       coef exp(coef) se(coef)     z     p
## fst 0.1722    1.1880   0.2681 0.642 0.521
## 
## Likelihood ratio test=0.42  on 1 df, p=0.515
## n= 112, number of events= 112 
##    (576 observations deleted due to missingness)
# Adjusted Cox model
survival::coxph(Surv(time_till_mets_new, mets_new) ~ fst + age + largest_basal_diameter + thickness_dls, data = data_survival)
## Call:
## survival::coxph(formula = Surv(time_till_mets_new, mets_new) ~ 
##     fst + age + largest_basal_diameter + thickness_dls, data = data_survival)
## 
##                            coef exp(coef) se(coef)     z        p
## fst                    0.070029  1.072540 0.315622 0.222 0.824409
## age                    0.028778  1.029197 0.009049 3.180 0.001470
## largest_basal_diameter 0.005612  1.005628 0.033678 0.167 0.867644
## thickness_dls          0.197509  1.218364 0.058280 3.389 0.000702
## 
## Likelihood ratio test=21.51  on 4 df, p=0.0002505
## n= 97, number of events= 97 
##    (591 observations deleted due to missingness)

Log-Rank Tests and Cox Models for Death

#Log-rank test: difference between the survival curves
survival::survdiff(Surv(time_till_death, death_new) ~ fst, data=data_survival)
## Call:
## survival::survdiff(formula = Surv(time_till_death, death_new) ~ 
##     fst, data = data_survival)
## 
## n=38, 650 observations deleted due to missingness.
## 
##        N Observed Expected (O-E)^2/E (O-E)^2/V
## fst=1  5        5   3.7489     0.417      0.49
## fst=2 32       31  33.1699     0.142      1.45
## fst=3  1        1   0.0811    10.408     10.70
## 
##  Chisq= 11.3  on 2 degrees of freedom, p= 0.004
# Traditional adjustment for confounders is to use a Cox model and estimate hazard ratio
# Unadjusted Cox model
survival::coxph(Surv(time_till_death, death_new) ~ fst, data = data_survival)
## Call:
## survival::coxph(formula = Surv(time_till_death, death_new) ~ 
##     fst, data = data_survival)
## 
##        coef exp(coef) se(coef)      z     p
## fst -0.1057    0.8997   0.5317 -0.199 0.842
## 
## Likelihood ratio test=0.04  on 1 df, p=0.8442
## n= 38, number of events= 37 
##    (650 observations deleted due to missingness)
# Adjusted Cox model
survival::coxph(Surv(time_till_death, death_new) ~ fst + age + largest_basal_diameter + thickness_dls, data = data_survival)
## Call:
## survival::coxph(formula = Surv(time_till_death, death_new) ~ 
##     fst + age + largest_basal_diameter + thickness_dls, data = data_survival)
## 
##                            coef exp(coef) se(coef)      z      p
## fst                     0.02131   1.02154  0.61731  0.035 0.9725
## age                     0.03981   1.04061  0.01741  2.287 0.0222
## largest_basal_diameter -0.06099   0.94083  0.07145 -0.854 0.3933
## thickness_dls           0.27933   1.32225  0.12835  2.176 0.0295
## 
## Likelihood ratio test=6.12  on 4 df, p=0.19
## n= 33, number of events= 33 
##    (655 observations deleted due to missingness)