Table 3 Associations of measures of timing of sunlight exposure in BCC and SCC cases and controls
Controls (n = 316) | Basal cell carcinoma (n = 218) | Squamous cell carcinoma (n = 169) | |||||
|---|---|---|---|---|---|---|---|
Variable | n (%) | n (%) | OR (95% CI)1 | OR (95% CI)2 | n (%) | OR (95% CI)1 | OR (95% CI)2 |
# of moles on forearms | |||||||
None | 220 (71.4) | 155 (71.8) | 1.00 (reference) | 1.00 (reference) | 115 (69.7) | 1.00 (reference) | 1.00 (reference) |
<10 | 80 (26.0) | 53 (24.5) | 0.84 (0.54-1.31) | 0.65 (0.40-1.06) | 39 (23.6) | 0.92 (0.56-1.52) | 0.94 (0.54-1.64) |
≥10 | 8 (2.6) | 8 (3.7) | 1.65 (0.57-4.77) | 1.75 (0.55-5.61) | 11 (6.7) | 3.27 (1.12-9.58) | 2.69 (0.75-9.59) |
ptrend = 0.96 | ptrend = 0.45 | ptrend = 0.25 | ptrend = 0.43 | ||||
# of moles on entire body | |||||||
None | 118 (39.1) | 79 (36.9) | 1.00 (reference) | 1.00 (reference) | 56 (34.1) | 1.00 (reference) | 1.00 (reference) |
<10 | 147 (48.7) | 107 (50.0) | 1.11 (0.73-1.67) | 1.03 (0.66-1.60) | 76 (46.3) | 1.15 (0.72-1.86) | 1.22 (0.71-2.09) |
≥10 | 37 (12.3) | 28 (13.1) | 1.18 (0.64-2.19) | 1.06 (0.55-2.04) | 32 (19.5) | 2.12 (1.11-4.06) | 2.16 (1.03-4.52) |
ptrend = 0.54 | ptrend = 0.86 | ptrend = 0.04 | ptrend = 0.06 | ||||
Age at 1st blistering sunburn | |||||||
None | 101 (32.9) | 54 (25.2) | 1.00 (reference) | 1.00 (reference) | 38 (23.5) | 1.00 (reference) | 1.00 (reference) |
<10 years | 62 (20.2) | 47 (22.0) | 1.97 (1.14-3.42) | 1.35 (0.73-2.49) | 46 (28.4) | 2.25 (1.22-4.13) | 1.07 (0.53-2.15) |
10–20 years | 108 (35.2) | 84 (39.3) | 2.15 (1.32-3.52) | 1.73 (1.00-2.99) | 65 (40.1) | 2.37 (1.34-4.21) | 1.62 (0.86-3.04) |
>20 years | 36 (11.7) | 29 (13.6) | 1.71 (0.89-3.28) | 1.67 (0.83-3.37) | 13 (8.0) | 0.96 (0.42-2.20) | 0.81 (0.33-2.01) |
ptrend = 0.01 | ptrend = 0.05 | ptrend = 0.17 | ptrend = 0.53 | ||||
Age at 1st tanning bed use | |||||||
Never used | 209 (67.0) | 175 (80.3) | 1.00 (reference) | 1.00 (reference) | 127 (76.5) | 1.00 (reference) | 1.00 (reference) |
≤20 years | 38 (12.2) | 20 (9.2) | 1.09 (0.58-2.06) | 1.10 (0.55-2.18) | 23 (13.9) | 1.97 (1.01-3.85) | 1.97 (0.91-4.27) |
>20 years | 65 (20.8) | 23 (10.6) | 0.64 (0.64-1.12) | 0.56 (0.30-1.05) | 16 (9.6) | 0.77 (0.40-1.50) | 0.78 (0.37-1.65) |
ptrend = 0.46 | ptrend = 0.33 | ptrend = 0.96 | ptrend = 0.98 | ||||
Daily sunlight exposure by age at exposure | |||||||
Teens | |||||||
Low | 63 (20.9) | 27 (13.6) | 1.00 (reference) | 1.00 (reference) | 21 (13.2) | 1.00 (reference) | 1.00 (reference) |
Medium | 104 (34.4) | 68 (34.2) | 1.28 (0.71-2.30) | 1.18 (0.62-2.25) | 55 (34.6) | 1.24 (0.64-2.42) | 0.94 (0.45-1.97) |
High | 135 (44.7) | 104 (52.3) | 1.38 (0.78-2.43) | 1.47 (0.78-2.77) | 83 (52.2) | 1.43 (0.75-2.73) | 1.40 (0.68-2.89) |
Twenties | |||||||
Low | 121 (40.2) | 62 (31.0) | 1.00 (reference) | 1.00 (reference) | 53 (33.3) | 1.00 (reference) | 1.00 (reference) |
Medium | 114 (37.9) | 79 (39.5) | 1.20 (0.77-1.88) | 1.35 (0.82-2.21) | 51 (32.1) | 0.82 (0.49-1.37) | 0.97 (0.54-1.73) |
High | 66 (21.9) | 59 (29.5) | 1.22 (0.73-2.31) | 1.31 (0.75-2.31) | 55 (34.6) | 1.40 (0.80-2.44) | 1.56 (0.83-2.91) |
Thirties | |||||||
Low | 152 (51.9) | 87 (43.9) | 1.00 (reference) | 1.00 (reference) | 64 (40.3) | 1.00 (reference) | 1.00 (reference) |
Medium | 103 (35.2) | 63 (31.8) | 0.90 (0.58-1.39) | 0.98 (0.60-1.58) | 62 (39.0) | 1.08 (0.66-1.75) | 1.36 (0.78-2.37) |
High | 38 (13.0) | 48 (24.2) | 1.20 (0.68-2.10) | 1.28 (0.69-2.36) | 33 (20.8) | 1.15 (0.61-2.18) | 1.30 (0.63-2.68) |
Past 10 years | |||||||
Low | 126 (57.3) | 76 (44.2) | 1.00 (reference) | 1.00 (reference) | 80 (54.1) | 1.00 (reference) | 1.00 (reference) |
Medium | 65 (29.5) | 59 (34.3) | 1.05 (0.64-1.74) | 1.15 (0.66-2.01) | 40 (27.0) | 0.77 (0.45-1.31) | 1.13 (0.61-2.10) |
High | 29 (13.2) | 37 (21.5) | 1.41 (0.74-2.68) | 1.62 (0.79-3.30) | 28 (18.9) | 1.16 (0.59-2.25) | 1.57 (0.73-3.36) |