Phenotypic and genotypic characteristics of melanoma cases in families with CDK4 germline mutations
| Variable* | Number | % |
|---|---|---|
| Sex (N=103) | ||
| Male | 44 | 42.7 |
| Female | 59 | 57.3 |
| Number of primary melanomas in affected subjects (N=103) | ||
| One | 60 | 58.3 |
| Multiple | 43 | 41.7 |
| Mean | 2.1 | – |
| CDK4 mutation status of affected subjects (N=103) | ||
| Subjects (N=77) in R24H families | ||
| CDK4 mutation positive | 41 | 39.8 |
| CDK4 mutation negative | 0 | 0.0 |
| Obligate CDK4 mutation carriers† | 7 | 6.8 |
| Unknown mutation status† | 29 | 28.2 |
| Subjects (N=26) in R24C families | ||
| CDK4 mutation positive | 21 | 20.4 |
| CDK4 mutation negative | 0 | 0.0 |
| Obligate CDK4 mutation carriers† | 0 | 0.0 |
| Unknown mutation status† | 5 | 4.9 |
| Age at first melanoma diagnosis (N=95) | ||
| <30 years | 20 | 21.1 |
| 30–39 years | 30 | 31.6 |
| 40–49 years | 24 | 25.3 |
| 50–59 years | 14 | 14.7 |
| ≥60 years | 7 | 7.4 |
| Missing data‡ | 8 | – |
| Mean (years) | 40.4 | – |
| Median (years) | 39.0 | – |
| Anatomic location (N=140)§ | ||
| Head/neck | 31 | 22.1 |
| Limbs | 66 | 47.1 |
| Trunk | 43 | 30.7 |
| Missing data‡ | 28 | – |
| Anatomic location, first primary melanoma only (N=81) | ||
| Head/neck | 17 | 21.0 |
| Limbs | 34 | 42.0 |
| Trunk | 30 | 37.0 |
| Missing data‡ | 21 | – |
| Histologic type (N=95)§ | ||
| SSM | 71 | 74.7 |
| NM | 3 | 3.2 |
| LMM | 1 | 1.1 |
| In situ melanoma | 20 | 21.1 |
| Melanoma unclassified or classification unknown‡ | 73 | – |
| Histologic type, first primary melanoma only (N=48) | ||
| SSM | 34 | 70.8 |
| NM | 3 | 6.3 |
| LMM | 1 | 2.1 |
| In situ melanoma | 10 | 20.8 |
| Melanoma unclassified or classification unknown‡ | 54 | – |
*One melanoma case was recorded as MPM, but with no information on the actual number of melanomas. It was therefore excluded when calculating the mean number of melanomas and when summarising anatomic location and histologic type.
†DNA was not available for these cases.
‡Missing data are not included in the parentheses (N=) and not included when calculating percentages.
§For persons with MPM, information about the first three registered tumours was recorded.
LMM, lentigo malignant melanoma; MPM, multiple primary melanomas; NM, nodular melanoma; SSM, superficial spreading melanoma.