Table 2. Risk of Melanoma Overall and Site-Specific Risk of Melanoma According to Phenotypic Characteristics Among 161 540 Women.
| Characteristic | RR (95% CI)a | P Value for Heterogeneityb | ||||
|---|---|---|---|---|---|---|
| Total (N = 1310) | Trunk (n = 461) | Lower Limb (n = 520) | Upper Limb (n = 219) | Head and Neck (n = 110) | ||
| Skin color | ||||||
| Dark | 1 [Reference] | 1 [Reference] | 1 [Reference] | 1 [Reference] | 1 [Reference] | .84 |
| Medium | 1.44 (1.26-2.02) | 1.78 (1.16-2.75) | 1.23 (0.87-1.75) | 1.96 (1.02-3.77) | 0.86 (0.41-1.79) | |
| Light | 1.89 (1.49-2.39) | 2.32 (1.50-3.58) | 1.61 (1.14-2.30) | 2.22 (1.14-4.31) | 1.53 (0.75-3.11) | |
| P value for trend | <.001 | <.001 | .002 | .03 | .04 | NA |
| Hair color | ||||||
| Black or dark brown | 1 [Reference] | 1 [Reference] | 1 [Reference] | 1 [Reference] | 1 [Reference] | .62 |
| Brown | 1.25 (1.03-1.52) | 1.20 (0.87-1.66) | 1.42 (1.03-1.95) | 1.48 (0.91-2.41) | 0.70 (0.39-1.25) | |
| Blond or yellow | 1.97 (1.64-2.37) | 2.01 (1.48-2.72) | 2.20 (1.63-3.00) | 2.05 (1.29-3.28) | 1.20 (0.71-2.01) | |
| Red | 3.94 (3.03-5.10) | 3.30 (2.09-5.21) | 4.70 (3.11-7.11) | 4.97 (2.65-9.30) | 2.50 (1.09-5.73) | |
| P value for trend | <.001 | <.001 | <.001 | <.001 | .06 | NA |
| Freckling after sunbathing | ||||||
| No | 1 [Reference] | 1 [Reference] | 1 [Reference] | 1 [Reference] | 1 [Reference] | .35 |
| Yes | 1.31 (1.15-1.48) | 1.22 (0.99-1.51) | 1.42 (1.17-1.73) | 1.43 (1.05-1.96) | 0.98 (0.63-1.52) | |
| Large asymmetric nevi on legs, No. | ||||||
| 0 | 1 [Reference] | 1 [Reference] | 1 [Reference] | 1 [Reference] | 1 [Reference] | .02 |
| 1 | 1.77 (1.47-2.13) | 1.19 (0.81-1.76) | 2.72 (2.11-3.50) | 1.28 (0.77-2.14) | 0.84 (0.34-2.08) | |
| ≥2 | 2.83 (2.38-3.35) | 2.67 (1.96-3.63) | 3.38 (2.62-4.38) | 1.96 (1.22-3.17) | 2.85 (1.57-5.18) | |
| P value for trend | <.001 | <.001 | <.001 | .005 | .008 | NA |
| Small symmetric nevi on arms and legs, No. | ||||||
| 0 | 0.63 (0.48-0.85) | 0.56 (0.33-0.97) | 0.56 (0.35-0.89) | 0.61 (0.33-1.14) | 0.72 (0.33-1.59) | .31 |
| 1-10 | 1 [Reference] | 1 [Reference] | 1 [Reference] | 1 [Reference] | 1 [Reference] | |
| 11-50 | 1.51 (1.26-1.80) | 1.96 (1.43-2.70) | 1.39 (1.04-1.86) | 1.58 (1.03-2.42) | 1.38 (0.75-2.55) | |
| ≥51 | 2.50 (2.04-3.08) | 3.48 (2.42-5.00) | 2.49 (1.80-3.45) | 2.19 (1.28-3.74) | 2.56 (1.24-5.29) | |
| P value for trend | <.001 | <.001 | <.001 | <.001 | .004 | NA |
Abbreviations: NA, not applicable; RR, relative risk.
a
Poison regression analysis adjusted for attained age, birth cohort, skin color, hair color, large asymmetric nevi on legs, freckling after sunbathing, and residential ambient UV radiation exposure.
b
Test for difference by body site.