Table. Dermoscopic, RCM, Histopathologic, and Immunohistochemical Findings in 63 Pigmented Macules and 12 Sun-Damaged Controls.
| Technique | Variable Evaluated | Non-LM/LMM (n = 39) |
LM/LMM (n = 24) |
P Value for Non-LM/LMM vs LM/LMMa | Control Cases (n = 12) | P Value for Non-LM/LMM vs Controla |
|---|---|---|---|---|---|---|
| Dermoscopy, No. (%) | Asymmetric pigmented follicular openings | 7 (18) | 16 (67) | <.001b | 0 | .18 |
| Annular-granular pattern | 16 (41) | 10 (42) | >.99 | 0 | .01 | |
| Pigmented rhomboidal structures | 12 (31) | 18 (75) | .001 | 0 | .047 | |
| Homogeneous areas (obliterated hair follicles) | 4 (10) | 5 (21) | .28 | 0 | .56 | |
| Increased density of vascular network | 16 (41) | 10 (42) | >.99 | 1 (8) | .17 | |
| Targetlike patterns | 3 (8) | 10 (42) | .003b | 0 | >.99 | |
| Darkening at dermatoscopic examination | 6 (15) | 2 (8) | .70 | 0 | .32 | |
| Red rhomboidal structures | 5 (13) | 4 (17) | .72 | 1 (8) | >.99 | |
| Dustlike dots | 4 (10) | 7 (29) | .06 | 0 | .18 | |
| Fingerprint | 5 (13) | 2 (8) | .70 | 1 (8) | >.99 | |
| Pseudonetwork | 22 (56) | 18 (75) | .18 | 1 (8) | .003 | |
| RCM, No. (%) | Nonedged dermal papillac | 0 | 4 (17) | .02 | 0 | NI |
| Round, large pagetoid cellsc | 5 (13) | 16 (67) | <.001b | 0 | .32 | |
| ≥3 Atypical cells at DEJc | 9 (23) | 19 (79) | <.001 | 0 | .09 | |
| Follicular localization of pagetoid cells and/or atypical junctional cellsc | 5 (13) | 13 (54) | .001b | 0 | .32 | |
| Nucleated cells in dermal papillac | 1 (3) | 6 (25) | .01 | 0 | >.99 | |
| Broadened honeycombed patternc | 4 (10) | 0 | .29 | 1 (8) | >.99 | |
| Epidermal disarray | 10 (26) | 16 (67) | .002 | 3 (25) | >.99 | |
| Epidermal cords and/or bulbous projections | 15 (38) | 2 (8) | .01 | 1 (8) | .07 | |
| Dendritic pagetoid cells | 20 (51) | 20 (83) | .02 | 0 | .001 | |
| Edged papilla | 15 (38) | 2 (8) | .01 | 3 (25) | .50 | |
| Nonvisible papilla | 23 (59) | 18 (75) | .28 | 9 (75) | .003 | |
| Melanophages | 25 (64) | 14 (58) | .79 | 1 (8) | .002 | |
| Enlarged vessels | 11 (28) | 2 (9)d | .11 | 0 | .09 | |
| Score LM, mean (SD) | 0.54 (0.91) | 3.25 (1.29) | <.001 | −0.08 (0.29) | .001 | |
| Histopathology, No. (%) | Epidermal atrophy | 14 (36) | 11 (46) | .60 | 4 (33) | >.99 |
| Flattening of dermal papilla | 10 (26) | 8 (33) | .57 | 3 (25) | >.99 | |
| Epidermal hyperplasia | 17 (44) | 6 (25) | .18 | 1 (8) | .04 | |
| Basal melanocytic hyperplasia H&E | 5 (13) | 21 (88) | <.001 | 0 | .56 | |
| Basal pigmentation | 19 (49) | 18 (75) | .06 | 2 (17) | .09 | |
| Atypia in keratinocytes | 19 (49) | 6 (25) | .07 | 4 (33) | .35 | |
| Atypia in melanocytes | 3 (8) | 21 (88) | <.001 | 0 | >.99 | |
| Perifollicular localization of melanocytes | 1 (3) | 13 (54) | <.001 | 0 | >.99 | |
| Melanocytes in rete ridges | 4 (10) | 10 (42) | .01 | 0 | .56 | |
| Junctional melanocytic nests | 2 (5) | 16 (67) | <.001 | 0 | >.99 | |
| Pagetoid spreading in 1 mm | 0 | 13 (54) | <.001 | 0 | NI | |
| Melanophages | 28 (72) | 20 (83) | .37 | 0 | <.001 | |
| Inflammatory infiltrate | 31 (82)e | 19 (79) | .82 | 6 (50) | .06 | |
| Immunohistochemistry | Hyperplasia of basal melanocytes, No. (%) | |||||
| H&E | 5 (13) | 21 (88) | <.001 | 0 | .32 | |
| Melan-A | 14 (36) | 23 (96) | <.001 | 0 | .02 | |
| MITF | 14 (36) | 23 (96) | <.001 | 0 | .02 | |
| SOX10 | 6 (15) | 21 (88) | <.001 | 0 | .32 | |
| Density of basal melanocytes, mean (SD), melanocytes/mm | ||||||
| H&E | 9.1 (6.7) | 29.8 (17.0) | <.001 | 10.3 (5.5) | .60 | |
| Melan-A | 26.5 (15.3) | 67.4 (27.1) | <.001 | 19.3 (7.0) | .03 | |
| MITF | 27 (16.1) | 54 (19.9) | <.001 | 21.3 (7.4) | .24 | |
| SOX10 | 27 (14.5) | 57.4 (25.5) | <.001 | 21.9 (9.1) | .26 | |
| Pagetoid spreading, No. (%) | ||||||
| H&E | 0 | 13 (54) | <.001 | 0 | NI | |
| Melan-A | 0 | 13 (54) | <.001 | 0 | NI | |
| MITF | 0 | 13 (54) | <.001 | 0 | NI | |
| SOX10 | 0 | 13 (54) | <.001 | 0 | NI | |
| No. of pagetoid cells, mean (SD), melanocytes/mm | ||||||
| H&E | 0.2 (0.7) | 3.6 (4.0) | <.001 | 0 | .40 | |
| Melan-A | 0.2 (1.0) | 5.2 (5.9) | .001 | 0 | .06 | |
| MITF | 0.1 (0.5) | 4.5 (6.0) | .002 | 0 | .07 | |
| SOX10 | 0.7 (3.0) | 4.8 (5.4) | .003 | 0 | .03 | |
Abbreviations: DEJ, dermal-epidermal junction; H&E, hematoxylin-eosin; LM, lentigo maligna; LMM, lentigo maligna melanoma; MITF, microphthalmia-associated transcription factor; NI, not indicated; RCM, reflectance confocal microscopy; SOX10, SRY-related HMG (high mobility box group)-box gene 10.
a
P value from univariate analysis.
b
Statistically significant also in multivariate analysis.
c
Criteria of LM algorithm according to Guitera et al.
d
Data available on 22 lesions.
e
Data available on 38 lesions.