Table 1.
Study demographics and histopathological characteristics
| Feature | No. DM (%) (n=16) |
No. In situ (%) (n=27) |
No. Non-DM invasive (%) (n=27) |
|
|---|---|---|---|---|
| Mean age in years [SD] | 68 [16.9] | 69 [14] | 63 [18.1] | |
| Gender | ||||
| Male | 12 (75) | 14 (52) | 13 (48) | |
| Female | 4 (25) | 13 (48) | 14 (52) | |
| Location | ||||
| Head/neck | 10 (63) | 19 (70) | 14 (52) | |
| Trunk | 2 (13) | 4 (15) | 3 (11) | |
| Limb | 3 (19) | 4 (15) | 7 (26) | |
| Acral | 1 (5) | 0 | 3 (11) | |
| Mean Breslow thickness in mm [SD] | 3.3 [2.36]a | N/a | 0.7 [0.56] | |
| DM Type, n=14b | Purec | Mixedc | ||
| 6/14 (43) | 8/14 (57) | |||
| Main or associated invasive melanoma typeb | ||||
| SSM | 0 | 2/14 (14) | 0 | 7 (26) |
| LMM | 0 | 2/14 (14) | 0 | 11 (41) |
| SSM/LMM | 0 | 0 | 0 | 2 (7) |
| ALM | 0 | 1/14 (7) | 0 | 3 (11) |
| Nodular/naevoid | 0 | 3/14 (21) | 0 | 4 (15) |
| In situ component (if present)b | ||||
| LM | 3/14 (21) | 3/14 (21) | 24 (89) | NR |
| In situ SSM | 1/14 (7) | 2/14 (14) | 2 (7) | NR |
| In situ ALM | 0 | 1/14 (7) | 0 | NR |
| In situ NS | 0 | 0 | 1 (4) | NR |
| No in situ | 2/14 (14) | 2/14 (14) | 0 | NR |
| Predominant cell typeb | ||||
| Spindle | 6/14 (43) | 6/14 (43) | N/a | 3 (11) |
| Spindle and Naevoid | 0 | 1/14 (7) | N/a | 1 (4) |
| Spindle and Epitheloid | 0 | 1/14 (7) | N/a | 1 (4) |
| Epitheloid | 0 | 0 | N/a | 12 (44) |
| Naevoid | 0 | 0 | N/a | 2 (7) |
| Epitheliod and Naevoid | 0 | 0 | N/a | 1 (4) |
| NS | 0 | 0 | N/a | 7 (26) |
a
3 cases missing Breslow depth data.
b
2 DM cases did not have histopathological slides available for central review.
c
Pure DM ≥90% desmoplasia, mixed desmoplastic melanoma <90% desmoplasia.
DM, desmoplastic melanoma; SSM, superficial spreading melanoma; LMM, lentigo maligna melanoma; ALM, acral lentiginous melanoma; LM, lentigo maligna; N/a, non applicable; NR, not recorded; NS, Non-specified.